chore(deps): remove jQuery

assets/css/_page/_single.scss

@@ -68,22 +68,25 @@
     h5,
     h6 {
       font-weight: bold;
+      margin: 1.2rem 0;
 
       .dark-theme & {
         font-weight: bolder;
       }
     }
 
-    h2,
-    h3,
-    h4,
-    h5,
-    h6 {
-      padding-top: .8rem;
-      padding-bottom: .3rem;
+    h2::before,
+    h3::before,
+    h4::before,
+    h5::before,
+    h6::before {
+      display: block;
+      content: "";
+      height: 1.2 * $header-height;
+      margin: -1.2 * $header-height 0 0;
     }
 
-    h2::before {
+    h2 > a:first-child::before {
       content: "#";
       margin-right: .3125rem;
       color: $single-link-color;
@@ -93,16 +96,18 @@
       }
     }
 
-    h3::before,
-    h4::before,
-    h5::before,
-    h6::before {
-      content: "|";
-      margin-right: .3125rem;
-      color: $single-link-color;
+    h3,
+    h4,
+    h5,
+    h6 {
+      & > a:first-child::before {
+        content: "|";
+        margin-right: .3125rem;
+        color: $single-link-color;
 
-      .dark-theme & {
-        color: $single-link-color-dark;
+        .dark-theme & {
+          color: $single-link-color-dark;
+        }
       }
     }