feat(style): improve style shortcode to support nesting (#263)

assets/css/_mixin/_summary.scss

@@ -15,6 +15,7 @@
       padding: 30% 0 0;
       position: relative;
       margin: 0.6rem auto;
+      @include transition(transform 0.4s ease);
 
       img {
         position: absolute;
@@ -24,6 +25,10 @@
         top: 0;
         object-fit: cover;
       }
+
+      &:hover {
+        @include transform(scale(1.01));
+      }
     }
 
     .single-title {