From 2912429ca63e9a50c8463739e839c05b479999c6 Mon Sep 17 00:00:00 2001
From: neon <18559658+neonsolstice@users.noreply.github.com>
Date: Tue, 1 Sep 2026 00:15:28 +0000
Subject: [PATCH] feat(reader): add epub typography controls

Preserve publisher typography by default while allowing explicit spacing and indentation overrides across reader clients.

Ref #1206
---
 client/src/features/reader/ReaderView.vue     |  36 ++-
 .../epub/components/ReaderSettingsPanel.vue   | 232 ++++++++++++++++--
 .../__tests__/ReaderSettingsPanel.spec.ts     |  77 +++++-
 .../__tests__/useReaderState.spec.ts          |  57 +++++
 .../reader/epub/composables/useReaderState.ts |  64 +++++
 .../composables/useReaderSettings.test.ts     | 168 +++++++++++--
 .../shared/composables/useReaderSettings.ts   |  28 ++-
 .../src/features/settings/EbookSettings.vue   | 220 ++++++++++++++++-
 .../settings/__tests__/EbookSettings.spec.ts  |  44 +++-
 client/src/locales/en.json                    |  15 ++
 packages/types/src/reader-settings.ts         |  23 +-
 .../reader-preferences.service.test.ts        | 200 ++++++++++++---
 .../reader-preferences.service.ts             |   9 +
 13 files changed, 1075 insertions(+), 98 deletions(-)

diff --git a/client/src/features/reader/ReaderView.vue b/client/src/features/reader/ReaderView.vue
index 001d40766..c7b7d28ae 100644
--- a/client/src/features/reader/ReaderView.vue
+++ b/client/src/features/reader/ReaderView.vue
@@ -83,6 +83,9 @@ const {
   setFontSize,
   setLineHeight,
   setParagraphSpacing,
+  setLetterSpacing,
+  setWordSpacing,
+  setTextIndent,
   setFontFamily,
   setFontWeight,
   setFontStyle,
@@ -111,7 +114,9 @@ const { onActivity, elapsedMinutes } = useReadingSession(
   { trackingEnabled },
 )
 
-const progress = useReaderProgress(bookId, fileId, elapsedMinutes, 0, { trackingEnabled })
+const progress = useReaderProgress(bookId, fileId, elapsedMinutes, 0, {
+  trackingEnabled,
+})
 const { cfi, chapterTitle, sectionIndex, totalSections, fraction, locationTotal, footerMode, cycleFooterMode, updateHeadsFeet } = progress
 
 const visibility = useVisibility()
@@ -320,7 +325,13 @@ onMounted(async () => {
   await annotations.load(bookId)
   const drawableAnnotations = annotations.annotations.value.filter((a): a is typeof a & { cfi: string } => a.cfi != null)
   if (drawableAnnotations.length > 0) {
-    addAnnotations(drawableAnnotations.map((a) => ({ cfi: a.cfi, color: a.color, style: a.style })))
+    addAnnotations(
+      drawableAnnotations.map((a) => ({
+        cfi: a.cfi,
+        color: a.color,
+        style: a.style,
+      })),
+    )
   }
   void hydrateSidebarLocationMeta()
 
@@ -344,6 +355,9 @@ const epubSetters: Record<string, (v: unknown) => void> = {
   fontSize: (v) => setFontSize(v as number),
   lineHeight: (v) => setLineHeight(v as number),
   paragraphSpacing: (v) => setParagraphSpacing(v as number),
+  letterSpacing: (v) => setLetterSpacing(v as number | null),
+  wordSpacing: (v) => setWordSpacing(v as number | null),
+  textIndent: (v) => setTextIndent(v as number | null),
   fontFamily: (v) => setFontFamily(v as string | null),
   fontWeight: (v) => setFontWeight(v as number),
   fontStyle: (v) => setFontStyle(v as EpubReaderSettings['fontStyle']),
@@ -478,7 +492,10 @@ function pruneSidebarLocationMeta(targets: string[]) {
   sidebarLocationMetaByCfi.value = next
 }
 
-function toSidebarLocationMeta(context: FoliateLocationContext): { chapterTitle: string | null; percentage: number | null } {
+function toSidebarLocationMeta(context: FoliateLocationContext): {
+  chapterTitle: string | null
+  percentage: number | null
+} {
   const percentage =
     typeof context.fraction === 'number' && Number.isFinite(context.fraction) ? Math.max(0, Math.min(100, Math.round(context.fraction * 100))) : null
   return { chapterTitle: context.chapterTitle, percentage }
@@ -505,7 +522,10 @@ async function hydrateSidebarLocationMeta() {
   )
 
   if (requestSeq !== sidebarLocationResolveSeq) return
-  sidebarLocationMetaByCfi.value = { ...sidebarLocationMetaByCfi.value, ...Object.fromEntries(entries) }
+  sidebarLocationMetaByCfi.value = {
+    ...sidebarLocationMetaByCfi.value,
+    ...Object.fromEntries(entries),
+  }
 }
 
 function onSearchQuery(q: string) {
@@ -633,13 +653,17 @@ watch(
       <div v-if="loading" class="absolute inset-0 flex items-center justify-center z-10 bg-background">
         <div class="flex flex-col items-center gap-3">
           <div class="w-8 h-8 rounded-full border-2 border-primary border-t-transparent animate-spin" />
-          <p class="text-sm text-muted-foreground">{{ t('reader.loadingBook') }}</p>
+          <p class="text-sm text-muted-foreground">
+            {{ t('reader.loadingBook') }}
+          </p>
         </div>
       </div>
 
       <div v-if="error && !loading" class="absolute inset-0 flex items-center justify-center z-10 p-8 bg-background">
         <div class="text-center max-w-sm">
-          <p class="text-sm font-medium mb-2 text-foreground">{{ t('reader.failedToLoadBook') }}</p>
+          <p class="text-sm font-medium mb-2 text-foreground">
+            {{ t('reader.failedToLoadBook') }}
+          </p>
           <p class="text-xs text-muted-foreground">{{ error }}</p>
         </div>
       </div>
diff --git a/client/src/features/reader/epub/components/ReaderSettingsPanel.vue b/client/src/features/reader/epub/components/ReaderSettingsPanel.vue
index 70937c268..de523fc91 100644
--- a/client/src/features/reader/epub/components/ReaderSettingsPanel.vue
+++ b/client/src/features/reader/epub/components/ReaderSettingsPanel.vue
@@ -4,8 +4,14 @@ import { useI18n } from 'vue-i18n'
 import {
   EPUB_FONT_SIZE_MAX,
   EPUB_FONT_SIZE_MIN,
+  EPUB_LETTER_SPACING_MAX,
+  EPUB_LETTER_SPACING_MIN,
   EPUB_PARAGRAPH_SPACING_MAX,
   EPUB_PARAGRAPH_SPACING_MIN,
+  EPUB_TEXT_INDENT_MAX,
+  EPUB_TEXT_INDENT_MIN,
+  EPUB_WORD_SPACING_MAX,
+  EPUB_WORD_SPACING_MIN,
   isCustomFontCssFamily,
   type FontNamedInstance,
   type FontVariant,
@@ -68,13 +74,34 @@ const modeOptions = computed(() => [
 ])
 
 const flowOptions = computed(() => [
-  { value: 'paginated', label: t('reader.settings.flow.paginated'), icon: BookOpen },
-  { value: 'scrolled', label: t('reader.settings.flow.scrolled'), icon: ScrollText },
+  {
+    value: 'paginated',
+    label: t('reader.settings.flow.paginated'),
+    icon: BookOpen,
+  },
+  {
+    value: 'scrolled',
+    label: t('reader.settings.flow.scrolled'),
+    icon: ScrollText,
+  },
 ])
 
 const spreadOptions = computed(() => [
-  { value: 'auto', label: t('reader.settings.spread.bookDefault'), icon: LayoutGrid },
-  { value: 'none', label: t('reader.settings.spread.singlePage'), icon: BookOpen },
+  {
+    value: 'auto',
+    label: t('reader.settings.spread.bookDefault'),
+    icon: LayoutGrid,
+  },
+  {
+    value: 'none',
+    label: t('reader.settings.spread.singlePage'),
+    icon: BookOpen,
+  },
+])
+
+const typographySourceOptions = computed(() => [
+  { value: 'book', label: t('reader.settings.bookDefault') },
+  { value: 'custom', label: t('reader.settings.custom') },
 ])
 
 const currentMode = computed(() => (props.state.isDark ? 'dark' : 'light'))
@@ -95,9 +122,21 @@ const paragraphSpacingLabel = computed(() =>
   props.state.paragraphSpacing === EPUB_PARAGRAPH_SPACING_MIN
     ? t('reader.settings.paragraphSpacingDefault')
     : t('reader.settings.paragraphSpacingValue', {
-        value: formatNumber(props.state.paragraphSpacing, { minimumFractionDigits: 1, maximumFractionDigits: 1 }),
+        value: formatNumber(props.state.paragraphSpacing, {
+          minimumFractionDigits: 1,
+          maximumFractionDigits: 1,
+        }),
       }),
 )
+const letterSpacingSource = computed(() => (props.state.letterSpacing === null ? 'book' : 'custom'))
+const wordSpacingSource = computed(() => (props.state.wordSpacing === null ? 'book' : 'custom'))
+const textIndentSource = computed(() => (props.state.textIndent === null ? 'book' : 'custom'))
+const letterSpacingValue = computed(() => props.state.letterSpacing ?? EPUB_LETTER_SPACING_MIN)
+const wordSpacingValue = computed(() => props.state.wordSpacing ?? EPUB_WORD_SPACING_MIN)
+const textIndentValue = computed(() => props.state.textIndent ?? EPUB_TEXT_INDENT_MIN)
+const letterSpacingLabel = computed(() => formatEmValue(letterSpacingValue.value, 2))
+const wordSpacingLabel = computed(() => formatEmValue(wordSpacingValue.value, 2))
+const textIndentLabel = computed(() => formatEmValue(textIndentValue.value, 2))
 
 const columnGapPercent = computed(() => Math.round(props.state.gap * 100))
 
@@ -110,15 +149,22 @@ function selectTheme(themeName: string) {
 }
 
 function decreaseTextSize() {
-  emit('update', { fontSize: Math.max(EPUB_FONT_SIZE_MIN, props.state.fontSize - 1) })
+  emit('update', {
+    fontSize: Math.max(EPUB_FONT_SIZE_MIN, props.state.fontSize - 1),
+  })
 }
 
 function increaseTextSize() {
-  emit('update', { fontSize: Math.min(EPUB_FONT_SIZE_MAX, props.state.fontSize + 1) })
+  emit('update', {
+    fontSize: Math.min(EPUB_FONT_SIZE_MAX, props.state.fontSize + 1),
+  })
 }
 
 function selectBuiltInFont(font: ReaderBuiltInFontOption) {
-  emit('update', { fontFamily: font.value, ...variantUpdateFor(builtInVariants()) })
+  emit('update', {
+    fontFamily: font.value,
+    ...variantUpdateFor(builtInVariants()),
+  })
 }
 
 function setLineHeight(value: number) {
@@ -129,6 +175,45 @@ function setParagraphSpacing(value: number) {
   emit('update', { paragraphSpacing: Math.round(value * 10) / 10 })
 }
 
+function formatEmValue(value: number, maximumFractionDigits: number): string {
+  return t('reader.settings.emValue', {
+    value: formatNumber(value, {
+      minimumFractionDigits: 0,
+      maximumFractionDigits,
+    }),
+  })
+}
+
+function setLetterSpacingSource(value: string) {
+  emit('update', {
+    letterSpacing: value === 'book' ? null : (props.state.letterSpacing ?? 0),
+  })
+}
+
+function setWordSpacingSource(value: string) {
+  emit('update', {
+    wordSpacing: value === 'book' ? null : (props.state.wordSpacing ?? 0),
+  })
+}
+
+function setTextIndentSource(value: string) {
+  emit('update', {
+    textIndent: value === 'book' ? null : (props.state.textIndent ?? 0),
+  })
+}
+
+function setLetterSpacing(value: number) {
+  emit('update', { letterSpacing: Math.round(value * 100) / 100 })
+}
+
+function setWordSpacing(value: number) {
+  emit('update', { wordSpacing: Math.round(value * 20) / 20 })
+}
+
+function setTextIndent(value: number) {
+  emit('update', { textIndent: Math.round(value * 4) / 4 })
+}
+
 function setPageWidth(value: number) {
   emit('update', { maxInlineSize: value })
 }
@@ -138,15 +223,21 @@ function setFlow(value: string) {
 }
 
 function setFixedLayoutSpread(value: string) {
-  emit('update', { fixedLayoutSpread: value as ReaderState['fixedLayoutSpread'] })
+  emit('update', {
+    fixedLayoutSpread: value as ReaderState['fixedLayoutSpread'],
+  })
 }
 
 function decreaseColumns() {
-  emit('update', { maxColumnCount: Math.max(COLUMN_MIN, props.state.maxColumnCount - 1) })
+  emit('update', {
+    maxColumnCount: Math.max(COLUMN_MIN, props.state.maxColumnCount - 1),
+  })
 }
 
 function increaseColumns() {
-  emit('update', { maxColumnCount: Math.min(COLUMN_MAX, props.state.maxColumnCount + 1) })
+  emit('update', {
+    maxColumnCount: Math.min(COLUMN_MAX, props.state.maxColumnCount + 1),
+  })
 }
 
 function setColumnGap(value: number) {
@@ -198,8 +289,16 @@ const customFontSections = computed(() => {
   const customFonts = props.customFonts
   if (!customFonts) return []
   return [
-    { key: 'server', label: t('reader.settings.fontServer'), families: customFonts.visibleServerFamilies.value },
-    { key: 'user', label: t('reader.settings.fontYours'), families: customFonts.families.value },
+    {
+      key: 'server',
+      label: t('reader.settings.fontServer'),
+      families: customFonts.visibleServerFamilies.value,
+    },
+    {
+      key: 'user',
+      label: t('reader.settings.fontYours'),
+      families: customFonts.families.value,
+    },
   ].filter((section) => section.families.length > 0)
 })
 
@@ -207,7 +306,11 @@ const hasCustomFontSections = computed(() => customFontSections.value.length > 0
 
 function selectCustomFont(family: FontFamily) {
   const cssFamilyName = props.customFonts?.getCssFamilyForDisplay(family.name, family.scope)
-  if (cssFamilyName) emit('update', { fontFamily: cssFamilyName, ...variantUpdateFor(familyVariants(family.variants)) })
+  if (cssFamilyName)
+    emit('update', {
+      fontFamily: cssFamilyName,
+      ...variantUpdateFor(familyVariants(family.variants)),
+    })
 }
 
 function isCustomFontSelected(family: FontFamily): boolean {
@@ -215,7 +318,10 @@ function isCustomFontSelected(family: FontFamily): boolean {
   return props.customFonts.isFontFamilySelected(family.name, props.state.fontFamily, family.scope)
 }
 
-const currentVariant = computed<FontVariant>(() => ({ weight: props.state.fontWeight, style: props.state.fontStyle }))
+const currentVariant = computed<FontVariant>(() => ({
+  weight: props.state.fontWeight,
+  style: props.state.fontStyle,
+}))
 
 /**
  * The styles the selected family offers. Built-in stacks have no file list to read, so
@@ -278,7 +384,9 @@ const cardBaseClass =
 <template>
   <section class="flex min-h-0 flex-col overflow-hidden bg-card text-card-foreground">
     <div class="flex shrink-0 items-center gap-2 border-b border-border bg-card px-4 py-2.5 transition-shadow" :class="isScrolled ? 'shadow-sm' : ''">
-      <h2 class="mr-auto text-sm font-semibold">{{ t('reader.settings.title') }}</h2>
+      <h2 class="mr-auto text-sm font-semibold">
+        {{ t('reader.settings.title') }}
+      </h2>
       <ReaderSegmentedControl
         class="w-[9.75rem] shrink-0"
         :options="modeOptions"
@@ -344,9 +452,17 @@ const cardBaseClass =
               aria-hidden="true"
               class="relative flex h-9 w-full items-center justify-center overflow-hidden rounded-md font-serif text-[13px] ring-2 ring-offset-2 ring-offset-card transition-all"
               :class="state.themeName === theme.name ? 'ring-primary' : 'ring-transparent group-hover:ring-border'"
-              :style="{ background: state.isDark ? theme.dark.bg : theme.light.bg, color: state.isDark ? theme.dark.fg : theme.light.fg }"
+              :style="{
+                background: state.isDark ? theme.dark.bg : theme.light.bg,
+                color: state.isDark ? theme.dark.fg : theme.light.fg,
+              }"
             >
-              <span class="absolute inset-x-0 top-0 h-[3px]" :style="{ background: state.isDark ? theme.dark.link : theme.light.link }" />
+              <span
+                class="absolute inset-x-0 top-0 h-[3px]"
+                :style="{
+                  background: state.isDark ? theme.dark.link : theme.light.link,
+                }"
+              />
               Aa
             </span>
             <span
@@ -385,7 +501,9 @@ const cardBaseClass =
           </div>
 
           <template v-for="section in customFontSections" :key="section.key">
-            <p class="mb-1.5 mt-3 text-[10px] font-semibold uppercase tracking-wide text-muted-foreground">{{ section.label }}</p>
+            <p class="mb-1.5 mt-3 text-[10px] font-semibold uppercase tracking-wide text-muted-foreground">
+              {{ section.label }}
+            </p>
             <div class="grid grid-cols-2 gap-2">
               <button
                 v-for="family in section.families"
@@ -421,7 +539,11 @@ const cardBaseClass =
                     ? 'border-primary bg-primary text-primary-foreground'
                     : 'border-border text-foreground hover:border-muted-foreground/40 hover:bg-muted'
                 "
-                :style="{ fontFamily: variantPreviewFamily, fontWeight: variant.weight, fontStyle: variant.style }"
+                :style="{
+                  fontFamily: variantPreviewFamily,
+                  fontWeight: variant.weight,
+                  fontStyle: variant.style,
+                }"
                 :aria-pressed="isVariantSelected(variant)"
                 @click="selectVariant(variant)"
               >
@@ -527,6 +649,72 @@ const cardBaseClass =
               @update:model-value="setColumnGap"
             />
 
+            <div class="space-y-2">
+              <p class="text-[13px] font-medium text-foreground">
+                {{ t('reader.settings.letterSpacing') }}
+              </p>
+              <ReaderSegmentedControl
+                :options="typographySourceOptions"
+                :model-value="letterSpacingSource"
+                :aria-label="t('reader.settings.letterSpacing')"
+                @update:model-value="setLetterSpacingSource"
+              />
+              <ReaderRangeField
+                v-if="state.letterSpacing !== null"
+                :model-value="letterSpacingValue"
+                :min="EPUB_LETTER_SPACING_MIN"
+                :max="EPUB_LETTER_SPACING_MAX"
+                :step="0.01"
+                :label="t('reader.settings.letterSpacing')"
+                :display-value="letterSpacingLabel"
+                @update:model-value="setLetterSpacing"
+              />
+            </div>
+
+            <div class="space-y-2">
+              <p class="text-[13px] font-medium text-foreground">
+                {{ t('reader.settings.wordSpacing') }}
+              </p>
+              <ReaderSegmentedControl
+                :options="typographySourceOptions"
+                :model-value="wordSpacingSource"
+                :aria-label="t('reader.settings.wordSpacing')"
+                @update:model-value="setWordSpacingSource"
+              />
+              <ReaderRangeField
+                v-if="state.wordSpacing !== null"
+                :model-value="wordSpacingValue"
+                :min="EPUB_WORD_SPACING_MIN"
+                :max="EPUB_WORD_SPACING_MAX"
+                :step="0.05"
+                :label="t('reader.settings.wordSpacing')"
+                :display-value="wordSpacingLabel"
+                @update:model-value="setWordSpacing"
+              />
+            </div>
+
+            <div class="space-y-2">
+              <p class="text-[13px] font-medium text-foreground">
+                {{ t('reader.settings.textIndent') }}
+              </p>
+              <ReaderSegmentedControl
+                :options="typographySourceOptions"
+                :model-value="textIndentSource"
+                :aria-label="t('reader.settings.textIndent')"
+                @update:model-value="setTextIndentSource"
+              />
+              <ReaderRangeField
+                v-if="state.textIndent !== null"
+                :model-value="textIndentValue"
+                :min="EPUB_TEXT_INDENT_MIN"
+                :max="EPUB_TEXT_INDENT_MAX"
+                :step="0.25"
+                :label="t('reader.settings.textIndent')"
+                :display-value="textIndentLabel"
+                @update:model-value="setTextIndent"
+              />
+            </div>
+
             <div class="flex items-center justify-between gap-3">
               <span :id="justifyLabelId" class="text-[13px] font-medium text-foreground">{{ t('reader.settings.justifyText') }}</span>
               <ToggleSwitch :model-value="state.justify" :aria-labelledby="justifyLabelId" @update:model-value="setJustify" />
@@ -548,7 +736,9 @@ const cardBaseClass =
           :aria-label="t('reader.settings.pageSpreads')"
           @update:model-value="setFixedLayoutSpread"
         />
-        <p class="mt-2 text-xs leading-snug text-muted-foreground">{{ t('reader.settings.pageSpreadsHint') }}</p>
+        <p class="mt-2 text-xs leading-snug text-muted-foreground">
+          {{ t('reader.settings.pageSpreadsHint') }}
+        </p>
       </div>
     </div>
   </section>
diff --git a/client/src/features/reader/epub/components/__tests__/ReaderSettingsPanel.spec.ts b/client/src/features/reader/epub/components/__tests__/ReaderSettingsPanel.spec.ts
index 274e74449..7a4831659 100644
--- a/client/src/features/reader/epub/components/__tests__/ReaderSettingsPanel.spec.ts
+++ b/client/src/features/reader/epub/components/__tests__/ReaderSettingsPanel.spec.ts
@@ -12,6 +12,9 @@ function makeState(overrides: Partial<ReaderState> = {}): ReaderState {
     fontSize: 16,
     lineHeight: 1.5,
     paragraphSpacing: 0,
+    letterSpacing: null,
+    wordSpacing: null,
+    textIndent: null,
     fontFamily: null,
     fontWeight: 400,
     fontStyle: 'normal',
@@ -58,6 +61,10 @@ function buttonByText(wrapper: VueWrapper, text: string) {
   return wrapper.findAll('button').find((button) => button.text() === text)
 }
 
+function groupByAriaLabel(wrapper: VueWrapper, label: string) {
+  return wrapper.find(`[role="group"][aria-label="${label}"]`)
+}
+
 /** Resolves the style chips through the group their heading labels, a11y wiring included. */
 function styleChips(wrapper: VueWrapper) {
   const group = wrapper.findAll('[role="group"]').find((candidate) => {
@@ -216,7 +223,14 @@ describe('ReaderSettingsPanel', () => {
   })
 
   it('emits advanced layout changes', async () => {
-    const wrapper = mountPanel({ state: makeState({ maxColumnCount: 2, gap: 0.05, justify: true, hyphenate: true }) })
+    const wrapper = mountPanel({
+      state: makeState({
+        maxColumnCount: 2,
+        gap: 0.05,
+        justify: true,
+        hyphenate: true,
+      }),
+    })
 
     await buttonByAriaLabel(wrapper, 'More columns').trigger('click')
     expect(wrapper.emitted('update')?.[0]).toEqual([{ maxColumnCount: 3 }])
@@ -231,6 +245,33 @@ describe('ReaderSettingsPanel', () => {
     expect(wrapper.emitted('update')?.[3]).toEqual([{ hyphenate: false }])
   })
 
+  it('offers publisher and custom typography controls with nullable overrides', async () => {
+    const wrapper = mountPanel()
+
+    expect(wrapper.text()).toContain('Letter spacing')
+    expect(wrapper.text()).toContain('Word spacing')
+    expect(wrapper.text()).toContain('First-line indent')
+    expect(groupByAriaLabel(wrapper, 'Letter spacing').get('button[aria-pressed="true"]').text()).toBe('Book')
+
+    await groupByAriaLabel(wrapper, 'Letter spacing').findAll('button')[1]!.trigger('click')
+    expect(wrapper.emitted('update')?.[0]).toEqual([{ letterSpacing: 0 }])
+
+    const customized = mountPanel({
+      state: makeState({ letterSpacing: 0.1, wordSpacing: 0.2, textIndent: 1 }),
+    })
+    await rangeByLabel(customized, 'Letter spacing')!.setValue('0.13')
+    await rangeByLabel(customized, 'Word spacing')!.setValue('0.35')
+    await rangeByLabel(customized, 'First-line indent')!.setValue('1.75')
+    await groupByAriaLabel(customized, 'Letter spacing').findAll('button')[0]!.trigger('click')
+
+    expect(customized.emitted('update')).toEqual([
+      [{ letterSpacing: 0.13 }],
+      [{ wordSpacing: 0.35 }],
+      [{ textIndent: 1.75 }],
+      [{ letterSpacing: null }],
+    ])
+  })
+
   it('resets only when the book carries overrides', async () => {
     const untouched = mountPanel({ canReset: false })
     expect(buttonByAriaLabel(untouched, 'Reset to defaults').attributes('disabled')).toBeDefined()
@@ -244,13 +285,17 @@ describe('ReaderSettingsPanel', () => {
   })
 
   it('offers spread choices and hides text controls for fixed-layout books', async () => {
-    const wrapper = mountPanel({ state: makeState({ fixedLayoutSpread: 'auto' }), isFixedLayout: true })
+    const wrapper = mountPanel({
+      state: makeState({ fixedLayoutSpread: 'auto' }),
+      isFixedLayout: true,
+    })
 
     expect(wrapper.text()).toContain('Page spreads')
     expect(wrapper.text()).toContain('Page color')
     expect(wrapper.text()).not.toContain('Text size')
     expect(wrapper.text()).not.toContain('Reading flow')
     expect(wrapper.text()).not.toContain('Advanced layout')
+    expect(wrapper.text()).not.toContain('Letter spacing')
 
     await buttonByText(wrapper, 'Single page')?.trigger('click')
     expect(wrapper.emitted('update')?.[0]).toEqual([{ fixedLayoutSpread: 'none' }])
@@ -279,7 +324,13 @@ describe('ReaderSettingsPanel', () => {
     })
 
     it('marks the style in use as pressed', () => {
-      const wrapper = mountPanel({ state: makeState({ fontFamily: 'serif', fontWeight: 700, fontStyle: 'normal' }) })
+      const wrapper = mountPanel({
+        state: makeState({
+          fontFamily: 'serif',
+          fontWeight: 700,
+          fontStyle: 'normal',
+        }),
+      })
 
       expect(styleChip(wrapper, 'Bold')?.attributes('aria-pressed')).toBe('true')
       expect(styleChip(wrapper, 'Regular')?.attributes('aria-pressed')).toBe('false')
@@ -299,14 +350,20 @@ describe('ReaderSettingsPanel', () => {
           }),
         ]),
       ])
-      const wrapper = mountPanel({ state: makeState({ fontFamily: userCss('Inter') }), customFonts })
+      const wrapper = mountPanel({
+        state: makeState({ fontFamily: userCss('Inter') }),
+        customFonts,
+      })
 
       expect(styleChipLabels(wrapper)).toEqual(['Thin', 'Book', 'Heavy'])
     })
 
     it('hides the row for a family that offers a single style', () => {
       const customFonts = makeCustomFonts([makeFamily('Solo', [makeFont()])])
-      const wrapper = mountPanel({ state: makeState({ fontFamily: userCss('Solo') }), customFonts })
+      const wrapper = mountPanel({
+        state: makeState({ fontFamily: userCss('Solo') }),
+        customFonts,
+      })
 
       expect(wrapper.text()).not.toContain('Style')
       expect(styleChipLabels(wrapper)).toEqual([])
@@ -314,7 +371,10 @@ describe('ReaderSettingsPanel', () => {
 
     it('moves to the nearest style when the newly picked family lacks the current one', async () => {
       const customFonts = makeCustomFonts([makeFamily('Sparse', [makeFont({ weight: 300 }), makeFont({ id: 2, weight: 500 })])])
-      const wrapper = mountPanel({ state: makeState({ fontFamily: 'serif', fontWeight: 700 }), customFonts })
+      const wrapper = mountPanel({
+        state: makeState({ fontFamily: 'serif', fontWeight: 700 }),
+        customFonts,
+      })
 
       await buttonByText(wrapper, 'Sparse')?.trigger('click')
 
@@ -323,7 +383,10 @@ describe('ReaderSettingsPanel', () => {
 
     it('leaves the style alone when the newly picked family offers it', async () => {
       const customFonts = makeCustomFonts([makeFamily('Full', [makeFont({ weight: 400 }), makeFont({ id: 2, weight: 700 })])])
-      const wrapper = mountPanel({ state: makeState({ fontFamily: 'serif', fontWeight: 700 }), customFonts })
+      const wrapper = mountPanel({
+        state: makeState({ fontFamily: 'serif', fontWeight: 700 }),
+        customFonts,
+      })
 
       await buttonByText(wrapper, 'Full')?.trigger('click')
 
diff --git a/client/src/features/reader/epub/composables/__tests__/useReaderState.spec.ts b/client/src/features/reader/epub/composables/__tests__/useReaderState.spec.ts
index e6ad12673..850b083f9 100644
--- a/client/src/features/reader/epub/composables/__tests__/useReaderState.spec.ts
+++ b/client/src/features/reader/epub/composables/__tests__/useReaderState.spec.ts
@@ -8,6 +8,9 @@ describe('useReaderState', () => {
     state.setFontSize(100)
     state.setLineHeight(0.71)
     state.setParagraphSpacing(3)
+    state.setLetterSpacing(0.3)
+    state.setWordSpacing(0.8)
+    state.setTextIndent(8)
     state.setMaxColumnCount(0)
     state.setGap(0.9)
     state.setMaxInlineSize(200)
@@ -16,6 +19,9 @@ describe('useReaderState', () => {
     expect(state.fontSize.value).toBe(32)
     expect(state.lineHeight.value).toBe(0.8)
     expect(state.paragraphSpacing.value).toBe(2)
+    expect(state.letterSpacing.value).toBe(0.2)
+    expect(state.wordSpacing.value).toBe(0.5)
+    expect(state.textIndent.value).toBe(4)
     expect(state.maxColumnCount.value).toBe(1)
     expect(state.gap.value).toBe(0.5)
     expect(state.maxInlineSize.value).toBe(400)
@@ -23,8 +29,14 @@ describe('useReaderState', () => {
 
     state.setFontSize(1)
     state.setParagraphSpacing(-1)
+    state.setLetterSpacing(-1)
+    state.setWordSpacing(-1)
+    state.setTextIndent(-1)
     expect(state.fontSize.value).toBe(6)
     expect(state.paragraphSpacing.value).toBe(0)
+    expect(state.letterSpacing.value).toBe(0)
+    expect(state.wordSpacing.value).toBe(0)
+    expect(state.textIndent.value).toBe(0)
   })
 
   it('selects default theme when unknown theme name is set', () => {
@@ -154,6 +166,51 @@ describe('useReaderState', () => {
     expect(css).toContain('margin-block: unset !important;')
   })
 
+  it('preserves publisher typography when nullable controls are unset', () => {
+    const state = useReaderState()
+
+    expect(state.letterSpacing.value).toBeNull()
+    expect(state.wordSpacing.value).toBeNull()
+    expect(state.textIndent.value).toBeNull()
+    expect(state.generateCSS()).not.toContain('letter-spacing:')
+    expect(state.generateCSS()).not.toContain('word-spacing:')
+    expect(state.generateCSS()).not.toContain('text-indent:')
+  })
+
+  it('emits explicit zero typography overrides and can return to publisher styles', () => {
+    const state = useReaderState()
+    state.setLetterSpacing(0)
+    state.setWordSpacing(0)
+    state.setTextIndent(0)
+
+    const css = state.generateCSS()
+    expect(css).toContain('letter-spacing: 0em !important;')
+    expect(css).toContain('word-spacing: 0em !important;')
+    expect(css).toContain('text-indent: 0em !important;')
+
+    state.setLetterSpacing(null)
+    state.setWordSpacing(null)
+    state.setTextIndent(null)
+    expect(state.state.value).toMatchObject({
+      letterSpacing: null,
+      wordSpacing: null,
+      textIndent: null,
+    })
+  })
+
+  it('generates em-based typography CSS for positive values', () => {
+    const state = useReaderState()
+    state.setLetterSpacing(0.12)
+    state.setWordSpacing(0.35)
+    state.setTextIndent(1.75)
+
+    const css = state.generateCSS()
+    expect(css).toContain('letter-spacing: 0.12em !important;')
+    expect(css).toContain('word-spacing: 0.35em !important;')
+    expect(css).toContain('text-indent: 1.75em !important;')
+    expect(css).toContain(':is(hgroup, header, figure, figcaption, blockquote, li) > p')
+  })
+
   describe('font style', () => {
     it('leaves weight and slant out of the CSS while they sit at their defaults', () => {
       const state = useReaderState()
diff --git a/client/src/features/reader/epub/composables/useReaderState.ts b/client/src/features/reader/epub/composables/useReaderState.ts
index 208d41fdf..934143d32 100644
--- a/client/src/features/reader/epub/composables/useReaderState.ts
+++ b/client/src/features/reader/epub/composables/useReaderState.ts
@@ -2,9 +2,15 @@ import { computed, ref } from 'vue'
 import {
   EPUB_FONT_SIZE_MAX,
   EPUB_FONT_SIZE_MIN,
+  EPUB_LETTER_SPACING_MAX,
+  EPUB_LETTER_SPACING_MIN,
   EPUB_PARAGRAPH_SPACING_MAX,
   EPUB_PARAGRAPH_SPACING_MIN,
   EPUB_READER_DEFAULTS,
+  EPUB_TEXT_INDENT_MAX,
+  EPUB_TEXT_INDENT_MIN,
+  EPUB_WORD_SPACING_MAX,
+  EPUB_WORD_SPACING_MIN,
   type EpubReaderSettings,
   type FontStyle,
 } from '@bookorbit/types'
@@ -16,6 +22,9 @@ export interface ReaderState {
   fontSize: number
   lineHeight: number
   paragraphSpacing: number
+  letterSpacing: number | null
+  wordSpacing: number | null
+  textIndent: number | null
   fontFamily: string | null
   fontWeight: number
   fontStyle: FontStyle
@@ -39,6 +48,9 @@ const defaults: ReaderState = {
   fontSize: 16,
   lineHeight: 1.5,
   paragraphSpacing: EPUB_READER_DEFAULTS.paragraphSpacing,
+  letterSpacing: EPUB_READER_DEFAULTS.letterSpacing,
+  wordSpacing: EPUB_READER_DEFAULTS.wordSpacing,
+  textIndent: EPUB_READER_DEFAULTS.textIndent,
   fontFamily: null,
   fontWeight: EPUB_READER_DEFAULTS.fontWeight,
   fontStyle: EPUB_READER_DEFAULTS.fontStyle,
@@ -58,6 +70,9 @@ export function useReaderState() {
   const fontSize = ref(defaults.fontSize)
   const lineHeight = ref(defaults.lineHeight)
   const paragraphSpacing = ref(defaults.paragraphSpacing)
+  const letterSpacing = ref<number | null>(defaults.letterSpacing)
+  const wordSpacing = ref<number | null>(defaults.wordSpacing)
+  const textIndent = ref<number | null>(defaults.textIndent)
   const fontFamily = ref<string | null>(defaults.fontFamily)
   const fontWeight = ref(defaults.fontWeight)
   const fontStyle = ref<FontStyle>(defaults.fontStyle)
@@ -78,6 +93,9 @@ export function useReaderState() {
     fontSize: fontSize.value,
     lineHeight: lineHeight.value,
     paragraphSpacing: paragraphSpacing.value,
+    letterSpacing: letterSpacing.value,
+    wordSpacing: wordSpacing.value,
+    textIndent: textIndent.value,
     fontFamily: fontFamily.value,
     fontWeight: fontWeight.value,
     fontStyle: fontStyle.value,
@@ -104,6 +122,9 @@ export function useReaderState() {
     const {
       lineHeight: lh,
       paragraphSpacing: ps,
+      letterSpacing: ls,
+      wordSpacing: ws,
+      textIndent: ti,
       justify: j,
       hyphenate: h,
       fontSize: fs,
@@ -157,6 +178,26 @@ export function useReaderState() {
       :is(hgroup, header) p {
           margin-block: unset !important;
       }`
+    const inlineSpacingDeclarations = [
+      ls === null ? '' : `letter-spacing: ${ls}em !important;`,
+      ws === null ? '' : `word-spacing: ${ws}em !important;`,
+    ].filter(Boolean)
+    const inlineSpacingRule = inlineSpacingDeclarations.length
+      ? `
+      p, li, blockquote, dd {
+          ${inlineSpacingDeclarations.join('\n          ')}
+      }`
+      : ''
+    const textIndentRule =
+      ti === null
+        ? ''
+        : `
+      p {
+          text-indent: ${ti}em !important;
+      }
+      :is(hgroup, header, figure, figcaption, blockquote, li) > p {
+          text-indent: unset !important;
+      }`
 
     return `
       ${fontFaceBlock}
@@ -240,6 +281,8 @@ export function useReaderState() {
           hyphens: ${h ? 'auto' : 'none'};
       }
       ${paragraphSpacingRule}
+      ${inlineSpacingRule}
+      ${textIndentRule}
       ::selection {
           background-color: rgba(128, 128, 128, 0.3);
       }
@@ -277,6 +320,15 @@ export function useReaderState() {
   function setParagraphSpacing(v: number) {
     paragraphSpacing.value = Math.max(EPUB_PARAGRAPH_SPACING_MIN, Math.min(EPUB_PARAGRAPH_SPACING_MAX, Math.round(v * 10) / 10))
   }
+  function setLetterSpacing(v: number | null) {
+    letterSpacing.value = clampNullable(v, EPUB_LETTER_SPACING_MIN, EPUB_LETTER_SPACING_MAX, 100)
+  }
+  function setWordSpacing(v: number | null) {
+    wordSpacing.value = clampNullable(v, EPUB_WORD_SPACING_MIN, EPUB_WORD_SPACING_MAX, 20)
+  }
+  function setTextIndent(v: number | null) {
+    textIndent.value = clampNullable(v, EPUB_TEXT_INDENT_MIN, EPUB_TEXT_INDENT_MAX, 4)
+  }
   function setFontFamily(v: string | null) {
     fontFamily.value = v
   }
@@ -326,6 +378,9 @@ export function useReaderState() {
     fontSize,
     lineHeight,
     paragraphSpacing,
+    letterSpacing,
+    wordSpacing,
+    textIndent,
     fontFamily,
     fontWeight,
     fontStyle,
@@ -347,6 +402,9 @@ export function useReaderState() {
     setFontSize,
     setLineHeight,
     setParagraphSpacing,
+    setLetterSpacing,
+    setWordSpacing,
+    setTextIndent,
     setFontFamily,
     setFontWeight,
     setFontStyle,
@@ -363,3 +421,9 @@ export function useReaderState() {
     setFontFaceCSS,
   }
 }
+
+function clampNullable(value: number | null, min: number, max: number, precision: number): number | null {
+  if (value === null) return null
+  const finiteValue = Number.isFinite(value) ? value : min
+  return Math.max(min, Math.min(max, Math.round(finiteValue * precision) / precision))
+}
diff --git a/client/src/features/reader/shared/composables/useReaderSettings.test.ts b/client/src/features/reader/shared/composables/useReaderSettings.test.ts
index 6373144f2..9e23e604c 100644
--- a/client/src/features/reader/shared/composables/useReaderSettings.test.ts
+++ b/client/src/features/reader/shared/composables/useReaderSettings.test.ts
@@ -5,11 +5,15 @@ import { CBX_READER_DEFAULTS, READER_GROUP_DEFAULTS, type PdfReaderSettings } fr
 const apiMock = vi.hoisted(() => vi.fn<(...args: unknown[]) => Promise<unknown>>())
 vi.mock('@/lib/api', () => ({ api: apiMock }))
 
-const toastMock = vi.hoisted(() => ({ success: vi.fn<(...args: unknown[]) => unknown>() }))
+const toastMock = vi.hoisted(() => ({
+  success: vi.fn<(...args: unknown[]) => unknown>(),
+}))
 vi.mock('vue-sonner', () => ({ toast: toastMock }))
 
 const useAuthMock = vi.hoisted(() => vi.fn<(...args: unknown[]) => unknown>(() => ({ user: ref(null) })))
-vi.mock('@/features/auth/composables/useAuth', () => ({ useAuth: useAuthMock }))
+vi.mock('@/features/auth/composables/useAuth', () => ({
+  useAuth: useAuthMock,
+}))
 
 import { useReaderSettings, useReaderDefaultSettings } from './useReaderSettings'
 
@@ -69,7 +73,10 @@ describe('useReaderSettings - load() with valid localStorage epub delta', () =>
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
     await s.load()
 
-    expect(s.effective.value).toMatchObject({ ...READER_GROUP_DEFAULTS.epub, fontSize: 24 })
+    expect(s.effective.value).toMatchObject({
+      ...READER_GROUP_DEFAULTS.epub,
+      fontSize: 24,
+    })
   })
 
   it('preserves the minimum EPUB font size', async () => {
@@ -101,6 +108,33 @@ describe('useReaderSettings - load() with valid localStorage epub delta', () =>
     expect(s.effective.value).toMatchObject({ paragraphSpacing: 0 })
   })
 
+  it('preserves nullable typography and explicit zero in per-book settings', async () => {
+    localStorage.setItem(
+      'reader:default:epub',
+      JSON.stringify({
+        ...READER_GROUP_DEFAULTS.epub,
+        letterSpacing: 0.12,
+        wordSpacing: 0.25,
+        textIndent: 1.5,
+      }),
+    )
+    localStorage.setItem(`reader:book:${BOOK_FILE_ID}`, JSON.stringify({ letterSpacing: null, wordSpacing: 0, textIndent: 0 }))
+
+    const s = useReaderSettings(BOOK_FILE_ID, 'epub')
+    await s.load()
+
+    expect(s.bookDelta.value).toEqual({
+      letterSpacing: null,
+      wordSpacing: 0,
+      textIndent: 0,
+    })
+    expect(s.effective.value).toMatchObject({
+      letterSpacing: null,
+      wordSpacing: 0,
+      textIndent: 0,
+    })
+  })
+
   it('filters invalid EPUB spread settings from localStorage deltas', async () => {
     const raw = { fontSize: 20, fixedLayoutSpread: 'two-page' }
     localStorage.setItem(`reader:book:${BOOK_FILE_ID}`, JSON.stringify(raw))
@@ -143,6 +177,23 @@ describe('useReaderSettings - load() with invalid localStorage value', () => {
     expect(localStorage.getItem(`reader:book:${BOOK_FILE_ID}`)).toBeNull()
   })
 
+  it('removes typography values outside their supported ranges', async () => {
+    localStorage.setItem(
+      `reader:book:${BOOK_FILE_ID}`,
+      JSON.stringify({
+        letterSpacing: 0.21,
+        wordSpacing: 0.51,
+        textIndent: 4.01,
+      }),
+    )
+
+    const s = useReaderSettings(BOOK_FILE_ID, 'epub')
+    await s.load()
+
+    expect(s.bookDelta.value).toBeNull()
+    expect(localStorage.getItem(`reader:book:${BOOK_FILE_ID}`)).toBeNull()
+  })
+
   it('removes localStorage key and leaves bookDelta null when value is not an object', async () => {
     localStorage.setItem(`reader:book:${BOOK_FILE_ID}`, JSON.stringify('not-an-object'))
 
@@ -193,12 +244,23 @@ describe('useReaderSettings - PDF validation', () => {
   })
 
   it('migrates wrapped mode and retains new read-only layout choices', async () => {
-    localStorage.setItem(`reader:book:${BOOK_FILE_ID}`, JSON.stringify({ scrollMode: 'wrapped', spread: 'auto', zoomMode: 'automatic' }))
+    localStorage.setItem(
+      `reader:book:${BOOK_FILE_ID}`,
+      JSON.stringify({
+        scrollMode: 'wrapped',
+        spread: 'auto',
+        zoomMode: 'automatic',
+      }),
+    )
 
     const settings = useReaderSettings(BOOK_FILE_ID, 'pdf')
     await settings.load()
 
-    expect(settings.bookDelta.value).toEqual({ scrollMode: 'vertical', spread: 'auto', zoomMode: 'automatic' })
+    expect(settings.bookDelta.value).toEqual({
+      scrollMode: 'vertical',
+      spread: 'auto',
+      zoomMode: 'automatic',
+    })
     expect(JSON.parse(localStorage.getItem(`reader:book:${BOOK_FILE_ID}`) ?? '{}')).toEqual({
       scrollMode: 'vertical',
       spread: 'auto',
@@ -226,7 +288,10 @@ describe('useReaderSettings - load() with valid cbx localStorage delta', () => {
     const s = useReaderSettings(BOOK_FILE_ID, 'cbz')
     await s.load()
 
-    expect(s.bookDelta.value).toMatchObject({ fitMode: 'fit-page', viewMode: 'two-page' })
+    expect(s.bookDelta.value).toMatchObject({
+      fitMode: 'fit-page',
+      viewMode: 'two-page',
+    })
     expect(s.isCustomized.value).toBe(true)
   })
 
@@ -236,7 +301,10 @@ describe('useReaderSettings - load() with valid cbx localStorage delta', () => {
     const valid = useReaderSettings(BOOK_FILE_ID, 'cbz')
     await valid.load()
 
-    expect(valid.bookDelta.value).toMatchObject({ spreadGap: 0, viewMode: 'two-page' })
+    expect(valid.bookDelta.value).toMatchObject({
+      spreadGap: 0,
+      viewMode: 'two-page',
+    })
 
     localStorage.setItem(`reader:book:${BOOK_FILE_ID}`, JSON.stringify({ spreadGap: 65, viewMode: 'two-page' }))
 
@@ -274,7 +342,9 @@ describe('useReaderSettings - updateBookSettings', () => {
   })
 
   it('calls api() with PUT when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
@@ -305,7 +375,9 @@ describe('useReaderSettings - resetBookSettings', () => {
   })
 
   it('calls api() with DELETE when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
@@ -321,7 +393,10 @@ describe('useReaderSettings - updateDefaultSettings', () => {
     s.updateDefaultSettings({ fontSize: 18 } as never)
 
     const stored = JSON.parse(localStorage.getItem('reader:default:epub') ?? 'null')
-    expect(stored).toMatchObject({ ...READER_GROUP_DEFAULTS.epub, fontSize: 18 })
+    expect(stored).toMatchObject({
+      ...READER_GROUP_DEFAULTS.epub,
+      fontSize: 18,
+    })
   })
 
   it('merges patch into existing defaultSettings', () => {
@@ -334,7 +409,9 @@ describe('useReaderSettings - updateDefaultSettings', () => {
   })
 
   it('calls api() with PUT when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
@@ -362,7 +439,9 @@ describe('useReaderSettings - resetDefaultSettings', () => {
   })
 
   it('calls api() with DELETE when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
@@ -390,7 +469,9 @@ describe('useReaderSettings - syncEnabled behavior', () => {
   })
 
   it('calls api() when user has syncReaderPreferences: true', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
@@ -400,7 +481,9 @@ describe('useReaderSettings - syncEnabled behavior', () => {
   })
 
   it('does not call api() when syncReaderPreferences is false', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: false } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: false } }),
+    })
 
     const s = useReaderSettings(BOOK_FILE_ID, 'epub')
     s.updateBookSettings({ fontSize: 22 } as never)
@@ -411,7 +494,9 @@ describe('useReaderSettings - syncEnabled behavior', () => {
 
 describe('useReaderSettings - syncFromDb (via load() when syncEnabled)', () => {
   beforeEach(() => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
   })
 
   it('updates bookDelta when api returns valid settings', async () => {
@@ -425,9 +510,11 @@ describe('useReaderSettings - syncFromDb (via load() when syncEnabled)', () => {
   })
 
   it('updates defaultSettings when api returns group key', async () => {
-    apiMock
-      .mockResolvedValueOnce(makeFakeResponse(false, {}))
-      .mockResolvedValueOnce(makeFakeResponse(true, { cbx: { fitMode: 'fit-width', viewMode: 'single' } }))
+    apiMock.mockResolvedValueOnce(makeFakeResponse(false, {})).mockResolvedValueOnce(
+      makeFakeResponse(true, {
+        cbx: { fitMode: 'fit-width', viewMode: 'single' },
+      }),
+    )
 
     const s = useReaderSettings(BOOK_FILE_ID, 'cbz')
     await s.load()
@@ -464,7 +551,10 @@ describe('useReaderDefaultSettings - load() with localStorage', () => {
     const s = useReaderDefaultSettings('epub')
     await s.load()
 
-    expect(s.effective.value).toMatchObject({ fontSize: 20, fixedLayoutSpread: 'auto' })
+    expect(s.effective.value).toMatchObject({
+      fontSize: 20,
+      fixedLayoutSpread: 'auto',
+    })
     expect(JSON.parse(localStorage.getItem('reader:default:epub') ?? '{}')).toMatchObject({ fixedLayoutSpread: 'auto' })
   })
 
@@ -476,10 +566,35 @@ describe('useReaderDefaultSettings - load() with localStorage', () => {
     const s = useReaderDefaultSettings('epub')
     await s.load()
 
-    expect(s.effective.value).toMatchObject({ fontSize: 20, paragraphSpacing: 0 })
+    expect(s.effective.value).toMatchObject({
+      fontSize: 20,
+      paragraphSpacing: 0,
+    })
     expect(JSON.parse(localStorage.getItem('reader:default:epub') ?? '{}')).toMatchObject({ paragraphSpacing: 0 })
   })
 
+  it('fills nullable publisher typography for older epub defaults in localStorage', async () => {
+    const stored = { ...READER_GROUP_DEFAULTS.epub, fontSize: 20 }
+    delete (stored as Record<string, unknown>).letterSpacing
+    delete (stored as Record<string, unknown>).wordSpacing
+    delete (stored as Record<string, unknown>).textIndent
+    localStorage.setItem('reader:default:epub', JSON.stringify(stored))
+
+    const s = useReaderDefaultSettings('epub')
+    await s.load()
+
+    expect(s.effective.value).toMatchObject({
+      letterSpacing: null,
+      wordSpacing: null,
+      textIndent: null,
+    })
+    expect(JSON.parse(localStorage.getItem('reader:default:epub') ?? '{}')).toMatchObject({
+      letterSpacing: null,
+      wordSpacing: null,
+      textIndent: null,
+    })
+  })
+
   it('merges cbx localStorage settings with CBX_READER_DEFAULTS', async () => {
     const stored = { fitMode: 'fit-width', viewMode: 'single' }
     localStorage.setItem('reader:default:cbx', JSON.stringify(stored))
@@ -487,7 +602,10 @@ describe('useReaderDefaultSettings - load() with localStorage', () => {
     const s = useReaderDefaultSettings<typeof CBX_READER_DEFAULTS>('cbz')
     await s.load()
 
-    expect(s.effective.value).toMatchObject({ ...CBX_READER_DEFAULTS, fitMode: 'fit-width' })
+    expect(s.effective.value).toMatchObject({
+      ...CBX_READER_DEFAULTS,
+      fitMode: 'fit-width',
+    })
   })
 
   it('falls back to group defaults when localStorage is empty', async () => {
@@ -515,7 +633,9 @@ describe('useReaderDefaultSettings - update', () => {
   })
 
   it('calls api() with PUT when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderDefaultSettings('epub')
@@ -544,7 +664,9 @@ describe('useReaderDefaultSettings - reset', () => {
   })
 
   it('calls api() with DELETE when sync is enabled', () => {
-    useAuthMock.mockReturnValue({ user: ref({ settings: { syncReaderPreferences: true } }) })
+    useAuthMock.mockReturnValue({
+      user: ref({ settings: { syncReaderPreferences: true } }),
+    })
     apiMock.mockResolvedValue({ ok: true })
 
     const s = useReaderDefaultSettings('epub')
diff --git a/client/src/features/reader/shared/composables/useReaderSettings.ts b/client/src/features/reader/shared/composables/useReaderSettings.ts
index e94cba249..bdb6904b4 100644
--- a/client/src/features/reader/shared/composables/useReaderSettings.ts
+++ b/client/src/features/reader/shared/composables/useReaderSettings.ts
@@ -8,9 +8,15 @@ import {
   CBX_READER_DEFAULTS,
   EPUB_FONT_SIZE_MAX,
   EPUB_FONT_SIZE_MIN,
+  EPUB_LETTER_SPACING_MAX,
+  EPUB_LETTER_SPACING_MIN,
   EPUB_PARAGRAPH_SPACING_MAX,
   EPUB_PARAGRAPH_SPACING_MIN,
   EPUB_READER_DEFAULTS,
+  EPUB_TEXT_INDENT_MAX,
+  EPUB_TEXT_INDENT_MIN,
+  EPUB_WORD_SPACING_MAX,
+  EPUB_WORD_SPACING_MIN,
   PDF_READER_DEFAULTS,
   type CbxReaderSettings,
   type EpubReaderSettings,
@@ -60,6 +66,10 @@ function isIntegerInRange(value: unknown, min: number, max: number): value is nu
   return Number.isInteger(value) && isNumberInRange(value, min, max)
 }
 
+function isNullableNumberInRange(value: unknown, min: number, max: number): value is number | null {
+  return value === null || isNumberInRange(value, min, max)
+}
+
 function sanitizeEpubPartialSettings(settings: unknown): Partial<EpubReaderSettings> | null {
   if (!isRecord(settings)) return null
 
@@ -89,6 +99,15 @@ function sanitizeEpubPartialSettings(settings: unknown): Partial<EpubReaderSetti
   if (isNumberInRange(settings.paragraphSpacing, EPUB_PARAGRAPH_SPACING_MIN, EPUB_PARAGRAPH_SPACING_MAX)) {
     out.paragraphSpacing = settings.paragraphSpacing
   }
+  if (isNullableNumberInRange(settings.letterSpacing, EPUB_LETTER_SPACING_MIN, EPUB_LETTER_SPACING_MAX)) {
+    out.letterSpacing = settings.letterSpacing
+  }
+  if (isNullableNumberInRange(settings.wordSpacing, EPUB_WORD_SPACING_MIN, EPUB_WORD_SPACING_MAX)) {
+    out.wordSpacing = settings.wordSpacing
+  }
+  if (isNullableNumberInRange(settings.textIndent, EPUB_TEXT_INDENT_MIN, EPUB_TEXT_INDENT_MAX)) {
+    out.textIndent = settings.textIndent
+  }
   if (isIntegerInRange(settings.maxColumnCount, 1, 10)) {
     out.maxColumnCount = settings.maxColumnCount
   }
@@ -311,7 +330,10 @@ export function useReaderSettings(bookFileId: number, format: string) {
 
   // Merges only the changed field(s) into the existing delta — never saves a full snapshot.
   function updateBookSettings(patch: Partial<ReaderSettings>) {
-    const next = { ...(bookDelta.value ?? undefined), ...patch } as Partial<ReaderSettings>
+    const next = {
+      ...(bookDelta.value ?? undefined),
+      ...patch,
+    } as Partial<ReaderSettings>
     bookDelta.value = next
     isCustomized.value = Object.keys(next).length > 0
     writeLs(lsBookKey(bookFileId), next)
@@ -331,7 +353,9 @@ export function useReaderSettings(bookFileId: number, format: string) {
     removeLs(lsBookKey(bookFileId))
 
     if (syncEnabled.value) {
-      api(`/api/v1/reader/preferences/${bookFileId}`, { method: 'DELETE' }).catch(() => {})
+      api(`/api/v1/reader/preferences/${bookFileId}`, {
+        method: 'DELETE',
+      }).catch(() => {})
     }
   }
 
diff --git a/client/src/features/settings/EbookSettings.vue b/client/src/features/settings/EbookSettings.vue
index e82d2aad7..02f1167d7 100644
--- a/client/src/features/settings/EbookSettings.vue
+++ b/client/src/features/settings/EbookSettings.vue
@@ -2,8 +2,14 @@
 import { computed, onMounted, onUnmounted, ref, useId, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import {
+  EPUB_LETTER_SPACING_MAX,
+  EPUB_LETTER_SPACING_MIN,
   EPUB_PARAGRAPH_SPACING_MAX,
   EPUB_PARAGRAPH_SPACING_MIN,
+  EPUB_TEXT_INDENT_MAX,
+  EPUB_TEXT_INDENT_MIN,
+  EPUB_WORD_SPACING_MAX,
+  EPUB_WORD_SPACING_MIN,
   isCustomFontCssFamily,
   type EpubReaderSettings,
   type FontNamedInstance,
@@ -39,6 +45,12 @@ const props = withDefaults(
 const { t } = useI18n()
 const fontStyleSelectId = `ebook-font-style-${useId()}`
 const paragraphSpacingInputId = `ebook-paragraph-spacing-${useId()}`
+const letterSpacingSourceId = `ebook-letter-spacing-source-${useId()}`
+const letterSpacingInputId = `ebook-letter-spacing-${useId()}`
+const wordSpacingSourceId = `ebook-word-spacing-source-${useId()}`
+const wordSpacingInputId = `ebook-word-spacing-${useId()}`
+const textIndentSourceId = `ebook-text-indent-source-${useId()}`
+const textIndentInputId = `ebook-text-indent-${useId()}`
 
 const { effective, load, update, reset } = useReaderDefaultSettings<EpubReaderSettings>('epub')
 
@@ -84,22 +96,90 @@ function fontStyleLabel(variant: FontNamedInstance): string {
   return t('settings.reader.fonts.weightItalicOf', { weight: base })
 }
 
-const selectedFontStyle = computed(() => variantKey({ weight: effective.value.fontWeight, style: effective.value.fontStyle }))
+const selectedFontStyle = computed(() =>
+  variantKey({
+    weight: effective.value.fontWeight,
+    style: effective.value.fontStyle,
+  }),
+)
 const paragraphSpacingLabel = computed(() =>
   effective.value.paragraphSpacing === EPUB_PARAGRAPH_SPACING_MIN
     ? t('settings.reader.ebook.paragraphSpacingDefault')
     : t('settings.reader.ebook.paragraphSpacingValue', {
-        value: formatNumber(effective.value.paragraphSpacing, { minimumFractionDigits: 1, maximumFractionDigits: 1 }),
+        value: formatNumber(effective.value.paragraphSpacing, {
+          minimumFractionDigits: 1,
+          maximumFractionDigits: 1,
+        }),
       }),
 )
+const letterSpacingValue = computed(() => effective.value.letterSpacing ?? EPUB_LETTER_SPACING_MIN)
+const wordSpacingValue = computed(() => effective.value.wordSpacing ?? EPUB_WORD_SPACING_MIN)
+const textIndentValue = computed(() => effective.value.textIndent ?? EPUB_TEXT_INDENT_MIN)
+const letterSpacingLabel = computed(() => formatEmValue(letterSpacingValue.value, 2))
+const wordSpacingLabel = computed(() => formatEmValue(wordSpacingValue.value, 2))
+const textIndentLabel = computed(() => formatEmValue(textIndentValue.value, 2))
 
 function selectFontStyle(event: Event) {
   const chosen = fontStyleOptions.value.find((option) => option.value === (event.target as HTMLSelectElement).value)
-  if (chosen) update({ fontWeight: chosen.variant.weight, fontStyle: chosen.variant.style })
+  if (chosen)
+    update({
+      fontWeight: chosen.variant.weight,
+      fontStyle: chosen.variant.style,
+    })
 }
 
 function setParagraphSpacing(event: Event) {
-  update({ paragraphSpacing: Number((event.target as HTMLInputElement).value) })
+  update({
+    paragraphSpacing: Number((event.target as HTMLInputElement).value),
+  })
+}
+
+function formatEmValue(value: number, maximumFractionDigits: number): string {
+  return t('settings.reader.ebook.emValue', {
+    value: formatNumber(value, {
+      minimumFractionDigits: 0,
+      maximumFractionDigits,
+    }),
+  })
+}
+
+function setLetterSpacingSource(event: Event) {
+  const source = (event.target as HTMLSelectElement).value
+  update({
+    letterSpacing: source === 'book' ? null : (effective.value.letterSpacing ?? 0),
+  })
+}
+
+function setWordSpacingSource(event: Event) {
+  const source = (event.target as HTMLSelectElement).value
+  update({
+    wordSpacing: source === 'book' ? null : (effective.value.wordSpacing ?? 0),
+  })
+}
+
+function setTextIndentSource(event: Event) {
+  const source = (event.target as HTMLSelectElement).value
+  update({
+    textIndent: source === 'book' ? null : (effective.value.textIndent ?? 0),
+  })
+}
+
+function setLetterSpacing(event: Event) {
+  update({
+    letterSpacing: Math.round(Number((event.target as HTMLInputElement).value) * 100) / 100,
+  })
+}
+
+function setWordSpacing(event: Event) {
+  update({
+    wordSpacing: Math.round(Number((event.target as HTMLInputElement).value) * 20) / 20,
+  })
+}
+
+function setTextIndent(event: Event) {
+  update({
+    textIndent: Math.round(Number((event.target as HTMLInputElement).value) * 4) / 4,
+  })
 }
 
 /**
@@ -109,7 +189,10 @@ function setParagraphSpacing(event: Event) {
 function selectFontFamily(event: Event) {
   const fontFamily = (event.target as HTMLSelectElement).value || null
   const variants = variantsForFamily(fontFamily)
-  const current = { weight: effective.value.fontWeight, style: effective.value.fontStyle }
+  const current = {
+    weight: effective.value.fontWeight,
+    style: effective.value.fontStyle,
+  }
 
   if (variants.some((variant) => isSameVariant(variant, current))) {
     update({ fontFamily })
@@ -145,7 +228,15 @@ function reconcileSavedFont() {
       weight: effective.value.fontWeight,
       style: effective.value.fontStyle,
     })
-    update(fallback ? { fontFamily: null, fontWeight: fallback.weight, fontStyle: fallback.style } : { fontFamily: null })
+    update(
+      fallback
+        ? {
+            fontFamily: null,
+            fontWeight: fallback.weight,
+            fontStyle: fallback.style,
+          }
+        : { fontFamily: null },
+    )
   }
 }
 
@@ -579,6 +670,123 @@ function setFixedLayoutSpreadNone() {
         {{ t('settings.reader.ebook.advanced') }}
       </p>
       <div class="settings-card">
+        <div class="px-4 py-3.5 md:px-5 md:py-4 bg-card">
+          <div class="mb-3 flex items-start justify-between gap-3">
+            <div>
+              <label :for="letterSpacingSourceId" class="settings-label">{{ t('settings.reader.ebook.letterSpacing') }}</label>
+              <p class="settings-hint">
+                {{ t('settings.reader.ebook.letterSpacingHint') }}
+              </p>
+            </div>
+            <select
+              :id="letterSpacingSourceId"
+              class="text-xs border border-border rounded-md px-2 py-1.5 bg-card text-foreground focus:outline-none focus:ring-1 focus:ring-primary"
+              :value="effective.letterSpacing === null ? 'book' : 'custom'"
+              @change="setLetterSpacingSource"
+            >
+              <option value="book">
+                {{ t('settings.reader.ebook.bookDefault') }}
+              </option>
+              <option value="custom">
+                {{ t('settings.reader.ebook.custom') }}
+              </option>
+            </select>
+          </div>
+          <div v-if="effective.letterSpacing !== null" class="flex items-center gap-3">
+            <input
+              :id="letterSpacingInputId"
+              type="range"
+              :min="EPUB_LETTER_SPACING_MIN"
+              :max="EPUB_LETTER_SPACING_MAX"
+              step="0.01"
+              class="w-full accent-primary cursor-pointer"
+              :value="letterSpacingValue"
+              :aria-label="t('settings.reader.ebook.letterSpacing')"
+              :aria-valuetext="letterSpacingLabel"
+              @input="setLetterSpacing"
+            />
+            <span class="settings-value w-16 text-right">{{ letterSpacingLabel }}</span>
+          </div>
+        </div>
+
+        <div class="px-4 py-3.5 md:px-5 md:py-4 bg-card">
+          <div class="mb-3 flex items-start justify-between gap-3">
+            <div>
+              <label :for="wordSpacingSourceId" class="settings-label">{{ t('settings.reader.ebook.wordSpacing') }}</label>
+              <p class="settings-hint">
+                {{ t('settings.reader.ebook.wordSpacingHint') }}
+              </p>
+            </div>
+            <select
+              :id="wordSpacingSourceId"
+              class="text-xs border border-border rounded-md px-2 py-1.5 bg-card text-foreground focus:outline-none focus:ring-1 focus:ring-primary"
+              :value="effective.wordSpacing === null ? 'book' : 'custom'"
+              @change="setWordSpacingSource"
+            >
+              <option value="book">
+                {{ t('settings.reader.ebook.bookDefault') }}
+              </option>
+              <option value="custom">
+                {{ t('settings.reader.ebook.custom') }}
+              </option>
+            </select>
+          </div>
+          <div v-if="effective.wordSpacing !== null" class="flex items-center gap-3">
+            <input
+              :id="wordSpacingInputId"
+              type="range"
+              :min="EPUB_WORD_SPACING_MIN"
+              :max="EPUB_WORD_SPACING_MAX"
+              step="0.05"
+              class="w-full accent-primary cursor-pointer"
+              :value="wordSpacingValue"
+              :aria-label="t('settings.reader.ebook.wordSpacing')"
+              :aria-valuetext="wordSpacingLabel"
+              @input="setWordSpacing"
+            />
+            <span class="settings-value w-16 text-right">{{ wordSpacingLabel }}</span>
+          </div>
+        </div>
+
+        <div class="px-4 py-3.5 md:px-5 md:py-4 bg-card">
+          <div class="mb-3 flex items-start justify-between gap-3">
+            <div>
+              <label :for="textIndentSourceId" class="settings-label">{{ t('settings.reader.ebook.textIndent') }}</label>
+              <p class="settings-hint">
+                {{ t('settings.reader.ebook.textIndentHint') }}
+              </p>
+            </div>
+            <select
+              :id="textIndentSourceId"
+              class="text-xs border border-border rounded-md px-2 py-1.5 bg-card text-foreground focus:outline-none focus:ring-1 focus:ring-primary"
+              :value="effective.textIndent === null ? 'book' : 'custom'"
+              @change="setTextIndentSource"
+            >
+              <option value="book">
+                {{ t('settings.reader.ebook.bookDefault') }}
+              </option>
+              <option value="custom">
+                {{ t('settings.reader.ebook.custom') }}
+              </option>
+            </select>
+          </div>
+          <div v-if="effective.textIndent !== null" class="flex items-center gap-3">
+            <input
+              :id="textIndentInputId"
+              type="range"
+              :min="EPUB_TEXT_INDENT_MIN"
+              :max="EPUB_TEXT_INDENT_MAX"
+              step="0.25"
+              class="w-full accent-primary cursor-pointer"
+              :value="textIndentValue"
+              :aria-label="t('settings.reader.ebook.textIndent')"
+              :aria-valuetext="textIndentLabel"
+              @input="setTextIndent"
+            />
+            <span class="settings-value w-16 text-right">{{ textIndentLabel }}</span>
+          </div>
+        </div>
+
         <!-- Max inline size -->
         <div class="px-4 py-3.5 md:px-5 md:py-4 bg-card">
           <div class="mb-3">
diff --git a/client/src/features/settings/__tests__/EbookSettings.spec.ts b/client/src/features/settings/__tests__/EbookSettings.spec.ts
index bd9ab7a92..591c80428 100644
--- a/client/src/features/settings/__tests__/EbookSettings.spec.ts
+++ b/client/src/features/settings/__tests__/EbookSettings.spec.ts
@@ -15,6 +15,9 @@ const readerSettingsMock = vi.hoisted(() => ({
       fontSize: 16,
       lineHeight: 1.5,
       paragraphSpacing: 0,
+      letterSpacing: null,
+      wordSpacing: null,
+      textIndent: null,
       maxColumnCount: 2,
       gap: 0.05,
       maxInlineSize: 720,
@@ -57,6 +60,9 @@ describe('EbookSettings', () => {
     readerSettingsMock.effective.value.fontFamily = null
     readerSettingsMock.effective.value.fontWeight = 400
     readerSettingsMock.effective.value.fontStyle = 'normal'
+    readerSettingsMock.effective.value.letterSpacing = null
+    readerSettingsMock.effective.value.wordSpacing = null
+    readerSettingsMock.effective.value.textIndent = null
     customFontsMock.cssFamilyAvailable.mockReturnValue(true)
     customFontsMock.fetchAllFonts.mockResolvedValue(undefined)
   })
@@ -92,7 +98,37 @@ describe('EbookSettings', () => {
     expect(slider.attributes('aria-valuetext')).toBe('Book default')
 
     await slider.setValue('1.2')
-    expect(readerSettingsMock.update).toHaveBeenCalledWith({ paragraphSpacing: 1.2 })
+    expect(readerSettingsMock.update).toHaveBeenCalledWith({
+      paragraphSpacing: 1.2,
+    })
+  })
+
+  it('switches typography defaults between publisher and custom values', async () => {
+    const wrapper = mount(EbookSettings, { props: { embedded: true } })
+    await flushPromises()
+
+    const letterSource = wrapper.get('select[id^="ebook-letter-spacing-source-"]')
+    expect((letterSource.element as HTMLSelectElement).value).toBe('book')
+
+    await letterSource.setValue('custom')
+    expect(readerSettingsMock.update).toHaveBeenCalledWith({
+      letterSpacing: 0,
+    })
+
+    readerSettingsMock.effective.value.letterSpacing = 0.1
+    const customized = mount(EbookSettings, { props: { embedded: true } })
+    await flushPromises()
+    const slider = customized.get('input[id^="ebook-letter-spacing-"]')
+    expect(slider.attributes('aria-valuetext')).toBe('0.1 em')
+    await slider.setValue('0.13')
+    expect(readerSettingsMock.update).toHaveBeenCalledWith({
+      letterSpacing: 0.13,
+    })
+
+    await customized.get('select[id^="ebook-letter-spacing-source-"]').setValue('book')
+    expect(readerSettingsMock.update).toHaveBeenCalledWith({
+      letterSpacing: null,
+    })
   })
 
   it('waits for both font catalogs before resetting an unavailable saved family', async () => {
@@ -107,6 +143,10 @@ describe('EbookSettings', () => {
     mount(EbookSettings, { props: { embedded: true } })
     await flushPromises()
 
-    expect(readerSettingsMock.update).toHaveBeenCalledWith({ fontFamily: null, fontWeight: 700, fontStyle: 'italic' })
+    expect(readerSettingsMock.update).toHaveBeenCalledWith({
+      fontFamily: null,
+      fontWeight: 700,
+      fontStyle: 'italic',
+    })
   })
 })
diff --git a/client/src/locales/en.json b/client/src/locales/en.json
index 125e3b869..2a42c690b 100644
--- a/client/src/locales/en.json
+++ b/client/src/locales/en.json
@@ -1926,6 +1926,15 @@
         "paragraphSpacingHint": "Space between paragraphs. Book default preserves the publisher's spacing.",
         "paragraphSpacingDefault": "Book default",
         "paragraphSpacingValue": "{value} em",
+        "letterSpacing": "Letter spacing",
+        "letterSpacingHint": "Space between letters. Book default preserves the publisher's spacing.",
+        "wordSpacing": "Word spacing",
+        "wordSpacingHint": "Space between words. Book default preserves the publisher's spacing.",
+        "textIndent": "First-line indent",
+        "textIndentHint": "Indent at the start of ordinary paragraphs. Book default preserves the publisher's indentation.",
+        "bookDefault": "Book default",
+        "custom": "Custom",
+        "emValue": "{value} em",
         "justify": "Justify text",
         "justifyHint": "Align text to both margins",
         "hyphenation": "Hyphenation",
@@ -8657,6 +8666,12 @@
       "paragraphSpacing": "Paragraph spacing",
       "paragraphSpacingDefault": "Default",
       "paragraphSpacingValue": "{value} em",
+      "letterSpacing": "Letter spacing",
+      "wordSpacing": "Word spacing",
+      "textIndent": "First-line indent",
+      "bookDefault": "Book",
+      "custom": "Custom",
+      "emValue": "{value} em",
       "pageWidth": "Page width",
       "pageWidthNarrow": "Narrow",
       "pageWidthMedium": "Medium",
diff --git a/packages/types/src/reader-settings.ts b/packages/types/src/reader-settings.ts
index 5c0ce81f7..432b7d1e4 100644
--- a/packages/types/src/reader-settings.ts
+++ b/packages/types/src/reader-settings.ts
@@ -6,6 +6,12 @@ export const EPUB_FONT_SIZE_MIN = 6;
 export const EPUB_FONT_SIZE_MAX = 32;
 export const EPUB_PARAGRAPH_SPACING_MIN = 0;
 export const EPUB_PARAGRAPH_SPACING_MAX = 2;
+export const EPUB_LETTER_SPACING_MIN = 0;
+export const EPUB_LETTER_SPACING_MAX = 0.2;
+export const EPUB_WORD_SPACING_MIN = 0;
+export const EPUB_WORD_SPACING_MAX = 0.5;
+export const EPUB_TEXT_INDENT_MIN = 0;
+export const EPUB_TEXT_INDENT_MAX = 4;
 export const CBX_SPREAD_GAP_MIN = 0;
 export const CBX_SPREAD_GAP_MAX = 64;
 
@@ -59,7 +65,10 @@ export function getFormatGroup(format: string): ReaderFormatGroup {
 /** Formats a given reader can open, so a caller can ask for "another file this same reader handles". */
 export function getOpenableFormatsForGroup(group: ReaderFormatGroup): string[] {
   return Object.entries(FORMAT_TO_GROUP)
-    .filter(([format, formatGroup]) => formatGroup === group && READER_OPENABLE_FORMATS.has(format))
+    .filter(
+      ([format, formatGroup]) =>
+        formatGroup === group && READER_OPENABLE_FORMATS.has(format),
+    )
     .map(([format]) => format);
 }
 
@@ -74,6 +83,9 @@ export interface EpubReaderSettings {
   fontSize: number; // EPUB_FONT_SIZE_MIN-EPUB_FONT_SIZE_MAX
   lineHeight: number; // 0.8-3.0
   paragraphSpacing: number; // EPUB_PARAGRAPH_SPACING_MIN-EPUB_PARAGRAPH_SPACING_MAX em; 0 preserves publisher spacing
+  letterSpacing: number | null; // null preserves publisher spacing
+  wordSpacing: number | null; // null preserves publisher spacing
+  textIndent: number | null; // null preserves publisher first-line indentation
   maxColumnCount: number; // 1-10
   gap: number; // 0-0.5 (column gap as fraction)
   maxInlineSize: number; // 400-1600 (max content width in px)
@@ -126,7 +138,11 @@ export type ReaderSettingsMap = {
   audio: AudioReaderSettings;
 };
 
-export type ReaderSettings = EpubReaderSettings | PdfReaderSettings | CbxReaderSettings | AudioReaderSettings;
+export type ReaderSettings =
+  | EpubReaderSettings
+  | PdfReaderSettings
+  | CbxReaderSettings
+  | AudioReaderSettings;
 
 export const EPUB_READER_DEFAULTS: EpubReaderSettings = {
   themeName: "default",
@@ -137,6 +153,9 @@ export const EPUB_READER_DEFAULTS: EpubReaderSettings = {
   fontSize: 16,
   lineHeight: 1.5,
   paragraphSpacing: EPUB_PARAGRAPH_SPACING_MIN,
+  letterSpacing: null,
+  wordSpacing: null,
+  textIndent: null,
   maxColumnCount: 2,
   gap: 0.05,
   maxInlineSize: 720,
diff --git a/server/src/modules/reader-preferences/reader-preferences.service.test.ts b/server/src/modules/reader-preferences/reader-preferences.service.test.ts
index 205e77529..0169a7959 100644
--- a/server/src/modules/reader-preferences/reader-preferences.service.test.ts
+++ b/server/src/modules/reader-preferences/reader-preferences.service.test.ts
@@ -77,7 +77,9 @@ describe('ReaderPreferencesService', () => {
 
   it('verifies file access before loading a per-book preference', async () => {
     const user = makeUser({ id: 12 });
-    mockRepo.findPreference.mockResolvedValueOnce({ settings: { zoomMode: 'fit-width' } });
+    mockRepo.findPreference.mockResolvedValueOnce({
+      settings: { zoomMode: 'fit-width' },
+    });
 
     const result = await service.getPreference(user, 42);
 
@@ -98,15 +100,25 @@ describe('ReaderPreferencesService', () => {
     const user = makeUser({ id: 4 });
     mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'pdf' });
 
-    await service.upsertPreference(user, 10, { zoomMode: 'custom', customScale: 1.4 });
+    await service.upsertPreference(user, 10, {
+      zoomMode: 'custom',
+      customScale: 1.4,
+    });
 
-    expect(mockRepo.upsertPreference).toHaveBeenCalledWith(4, 10, { zoomMode: 'custom', customScale: 1.4 });
+    expect(mockRepo.upsertPreference).toHaveBeenCalledWith(4, 10, {
+      zoomMode: 'custom',
+      customScale: 1.4,
+    });
   });
 
   it('accepts new PDF layout choices and normalizes legacy wrapped mode', async () => {
     const user = makeUser({ id: 4 });
 
-    await service.upsertPreference(user, 10, { scrollMode: 'wrapped', spread: 'auto', zoomMode: 'automatic' });
+    await service.upsertPreference(user, 10, {
+      scrollMode: 'wrapped',
+      spread: 'auto',
+      zoomMode: 'automatic',
+    });
 
     expect(mockRepo.upsertPreference).toHaveBeenCalledWith(4, 10, {
       scrollMode: 'vertical',
@@ -119,9 +131,17 @@ describe('ReaderPreferencesService', () => {
     const user = makeUser();
     mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'cbz' });
 
-    await service.upsertPreference(user, 11, { fitMode: 'fit-page', direction: 'rtl', spreadGap: 24 });
+    await service.upsertPreference(user, 11, {
+      fitMode: 'fit-page',
+      direction: 'rtl',
+      spreadGap: 24,
+    });
 
-    expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 11, { fitMode: 'fit-page', direction: 'rtl', spreadGap: 24 });
+    expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 11, {
+      fitMode: 'fit-page',
+      direction: 'rtl',
+      spreadGap: 24,
+    });
   });
 
   it('rejects comic spread gaps outside the supported range', async () => {
@@ -177,7 +197,9 @@ describe('ReaderPreferencesService', () => {
   });
 
   it('fills the gapless default for cbx payloads saved before spread gaps were supported', async () => {
-    const legacyCbxDefaults: Partial<typeof validCbxDefaults> = { ...validCbxDefaults };
+    const legacyCbxDefaults: Partial<typeof validCbxDefaults> = {
+      ...validCbxDefaults,
+    };
     delete legacyCbxDefaults.spreadGap;
 
     await service.upsertDefault(3, 'cbx', legacyCbxDefaults);
@@ -224,6 +246,9 @@ describe('ReaderPreferencesService', () => {
       fontSize: 16,
       lineHeight: 1.5,
       paragraphSpacing: 0,
+      letterSpacing: null,
+      wordSpacing: null,
+      textIndent: null,
       maxColumnCount: 2,
       gap: 0.05,
       maxInlineSize: 720,
@@ -240,14 +265,27 @@ describe('ReaderPreferencesService', () => {
       for (const mode of [0, 1, 2] as const) {
         vi.clearAllMocks();
         mockRepo.upsertDefault.mockResolvedValue(undefined);
-        await service.upsertDefault(1, 'epub', { ...validEpubDefaults, footerDisplayMode: mode });
+        await service.upsertDefault(1, 'epub', {
+          ...validEpubDefaults,
+          footerDisplayMode: mode,
+        });
         expect(mockRepo.upsertDefault).toHaveBeenCalledWith(1, 'epub', expect.objectContaining({ footerDisplayMode: mode }));
       }
     });
 
     it('rejects invalid footerDisplayMode values in epub defaults', async () => {
-      await expect(service.upsertDefault(1, 'epub', { ...validEpubDefaults, footerDisplayMode: 3 })).rejects.toThrow(BadRequestException);
-      await expect(service.upsertDefault(1, 'epub', { ...validEpubDefaults, footerDisplayMode: -1 })).rejects.toThrow(BadRequestException);
+      await expect(
+        service.upsertDefault(1, 'epub', {
+          ...validEpubDefaults,
+          footerDisplayMode: 3,
+        }),
+      ).rejects.toThrow(BadRequestException);
+      await expect(
+        service.upsertDefault(1, 'epub', {
+          ...validEpubDefaults,
+          footerDisplayMode: -1,
+        }),
+      ).rejects.toThrow(BadRequestException);
     });
 
     it('rejects a full epub default that omits the font style keys', async () => {
@@ -262,81 +300,181 @@ describe('ReaderPreferencesService', () => {
       await expect(service.upsertDefault(1, 'epub', missingParagraphSpacing)).rejects.toThrow(BadRequestException);
     });
 
+    it('accepts publisher typography defaults represented by null', async () => {
+      await service.upsertDefault(1, 'epub', validEpubDefaults);
+
+      expect(mockRepo.upsertDefault).toHaveBeenCalledWith(
+        1,
+        'epub',
+        expect.objectContaining({
+          letterSpacing: null,
+          wordSpacing: null,
+          textIndent: null,
+        }),
+      );
+    });
+
+    it.each(['letterSpacing', 'wordSpacing', 'textIndent'] as const)('rejects a full epub default that omits %s', async (field) => {
+      const missingField = Object.fromEntries(Object.entries(validEpubDefaults).filter(([key]) => key !== field));
+
+      await expect(service.upsertDefault(1, 'epub', missingField)).rejects.toThrow(BadRequestException);
+    });
+
     it('accepts a full epub default carrying a font weight and style', async () => {
-      await service.upsertDefault(1, 'epub', { ...validEpubDefaults, fontWeight: 700, fontStyle: 'italic' });
+      await service.upsertDefault(1, 'epub', {
+        ...validEpubDefaults,
+        fontWeight: 700,
+        fontStyle: 'italic',
+      });
 
       expect(mockRepo.upsertDefault).toHaveBeenCalledWith(1, 'epub', expect.objectContaining({ fontWeight: 700, fontStyle: 'italic' }));
     });
 
     it.each([[1], [350], [1000]])('accepts the CSS font weight %s', async (weight) => {
-      await service.upsertDefault(1, 'epub', { ...validEpubDefaults, fontWeight: weight });
+      await service.upsertDefault(1, 'epub', {
+        ...validEpubDefaults,
+        fontWeight: weight,
+      });
 
       expect(mockRepo.upsertDefault).toHaveBeenCalledWith(1, 'epub', expect.objectContaining({ fontWeight: weight }));
     });
 
     it.each([[0], [1001], [400.5]])('rejects the unsupported font weight %s', async (weight) => {
-      await expect(service.upsertDefault(1, 'epub', { ...validEpubDefaults, fontWeight: weight })).rejects.toThrow(BadRequestException);
+      await expect(
+        service.upsertDefault(1, 'epub', {
+          ...validEpubDefaults,
+          fontWeight: weight,
+        }),
+      ).rejects.toThrow(BadRequestException);
     });
 
     it('rejects an unsupported font style', async () => {
-      await expect(service.upsertDefault(1, 'epub', { ...validEpubDefaults, fontStyle: 'oblique' })).rejects.toThrow(BadRequestException);
+      await expect(
+        service.upsertDefault(1, 'epub', {
+          ...validEpubDefaults,
+          fontStyle: 'oblique',
+        }),
+      ).rejects.toThrow(BadRequestException);
     });
 
     it('accepts partial epub per-book settings with a font weight and style', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
-      await service.upsertPreference(user, 26, { fontWeight: 300, fontStyle: 'italic' });
+      await service.upsertPreference(user, 26, {
+        fontWeight: 300,
+        fontStyle: 'italic',
+      });
 
-      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 26, { fontWeight: 300, fontStyle: 'italic' });
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 26, {
+        fontWeight: 300,
+        fontStyle: 'italic',
+      });
     });
 
     it.each([[0], [0.8], [2]])('accepts paragraph spacing %s em', async (paragraphSpacing) => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await service.upsertPreference(user, 27, { paragraphSpacing });
 
-      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 27, { paragraphSpacing });
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 27, {
+        paragraphSpacing,
+      });
     });
 
     it.each([[-0.1], [2.1]])('rejects paragraph spacing %s em', async (paragraphSpacing) => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await expect(service.upsertPreference(user, 27, { paragraphSpacing })).rejects.toThrow(BadRequestException);
     });
 
+    it('accepts explicit zero and null typography overrides in partial epub settings', async () => {
+      const user = makeUser();
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
+
+      await service.upsertPreference(user, 28, {
+        letterSpacing: 0,
+        wordSpacing: null,
+        textIndent: 0,
+      });
+
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 28, {
+        letterSpacing: 0,
+        wordSpacing: null,
+        textIndent: 0,
+      });
+    });
+
+    it.each([
+      ['letterSpacing', -0.01],
+      ['letterSpacing', 0.21],
+      ['wordSpacing', -0.01],
+      ['wordSpacing', 0.51],
+      ['textIndent', -0.01],
+      ['textIndent', 4.01],
+    ])('rejects out-of-range typography setting %s=%s', async (field, value) => {
+      const user = makeUser();
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
+
+      await expect(service.upsertPreference(user, 29, { [field]: value })).rejects.toThrow(BadRequestException);
+    });
+
     it('accepts partial epub per-book settings with footerDisplayMode', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await service.upsertPreference(user, 20, { footerDisplayMode: 1 });
 
-      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 20, { footerDisplayMode: 1 });
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 20, {
+        footerDisplayMode: 1,
+      });
     });
 
     it('accepts partial epub per-book settings with fixedLayoutSpread', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await service.upsertPreference(user, 22, { fixedLayoutSpread: 'none' });
 
-      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 22, { fixedLayoutSpread: 'none' });
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 22, {
+        fixedLayoutSpread: 'none',
+      });
     });
 
     it('accepts the minimum epub font size', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await service.upsertPreference(user, 24, { fontSize: 6 });
 
-      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 24, { fontSize: 6 });
+      expect(mockRepo.upsertPreference).toHaveBeenCalledWith(7, 24, {
+        fontSize: 6,
+      });
     });
 
     it('rejects epub font sizes below the minimum', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await expect(service.upsertPreference(user, 25, { fontSize: 5 })).rejects.toThrow(BadRequestException);
       expect(mockRepo.upsertPreference).not.toHaveBeenCalled();
@@ -344,7 +482,9 @@ describe('ReaderPreferencesService', () => {
 
     it('rejects partial epub per-book settings with invalid footerDisplayMode', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await expect(service.upsertPreference(user, 21, { footerDisplayMode: 5 })).rejects.toThrow(BadRequestException);
       expect(mockRepo.upsertPreference).not.toHaveBeenCalled();
@@ -352,7 +492,9 @@ describe('ReaderPreferencesService', () => {
 
     it('rejects partial epub per-book settings with invalid fixedLayoutSpread', async () => {
       const user = makeUser();
-      mockBookService.verifyFileAccess.mockResolvedValueOnce({ format: 'epub' });
+      mockBookService.verifyFileAccess.mockResolvedValueOnce({
+        format: 'epub',
+      });
 
       await expect(service.upsertPreference(user, 23, { fixedLayoutSpread: 'two-page' })).rejects.toThrow(BadRequestException);
       expect(mockRepo.upsertPreference).not.toHaveBeenCalled();
diff --git a/server/src/modules/reader-preferences/reader-preferences.service.ts b/server/src/modules/reader-preferences/reader-preferences.service.ts
index 3337b15a5..4dda2e755 100644
--- a/server/src/modules/reader-preferences/reader-preferences.service.ts
+++ b/server/src/modules/reader-preferences/reader-preferences.service.ts
@@ -6,8 +6,14 @@ import {
   CSS_FONT_WEIGHT_MIN,
   EPUB_FONT_SIZE_MAX,
   EPUB_FONT_SIZE_MIN,
+  EPUB_LETTER_SPACING_MAX,
+  EPUB_LETTER_SPACING_MIN,
   EPUB_PARAGRAPH_SPACING_MAX,
   EPUB_PARAGRAPH_SPACING_MIN,
+  EPUB_TEXT_INDENT_MAX,
+  EPUB_TEXT_INDENT_MIN,
+  EPUB_WORD_SPACING_MAX,
+  EPUB_WORD_SPACING_MIN,
   READER_GROUP_DEFAULTS,
   getFormatGroup,
   type ReaderFormatGroup,
@@ -31,6 +37,9 @@ const EPUB_SETTINGS_SCHEMA = z
     fontSize: z.number().min(EPUB_FONT_SIZE_MIN).max(EPUB_FONT_SIZE_MAX),
     lineHeight: z.number().min(0.8).max(3),
     paragraphSpacing: z.number().min(EPUB_PARAGRAPH_SPACING_MIN).max(EPUB_PARAGRAPH_SPACING_MAX),
+    letterSpacing: z.number().min(EPUB_LETTER_SPACING_MIN).max(EPUB_LETTER_SPACING_MAX).nullable(),
+    wordSpacing: z.number().min(EPUB_WORD_SPACING_MIN).max(EPUB_WORD_SPACING_MAX).nullable(),
+    textIndent: z.number().min(EPUB_TEXT_INDENT_MIN).max(EPUB_TEXT_INDENT_MAX).nullable(),
     maxColumnCount: z.number().int().min(1).max(10),
     gap: z.number().min(0).max(0.5),
     maxInlineSize: z.number().int().min(400).max(1600),