diff --git a/_includes/toc.html b/_includes/toc.html
index 0f877267b39..888466d275b 100644
--- a/_includes/toc.html
+++ b/_includes/toc.html
@@ -3,7 +3,7 @@
 {% if enable_toc %}
   <div class="toc-border-cover z-3"></div>
   <section id="toc-wrapper" class="invisible position-sticky ps-0 pe-4 pb-4">
-    <h2 class="panel-heading ps-3 pb-2 mb-0">{{- site.data.locales[include.lang].panel.toc -}}</h2>
+    <h2 class="panel-heading ps-3 pb-1 mb-0">{{- site.data.locales[include.lang].panel.toc -}}</h2>
     <nav id="toc"></nav>
   </section>
 {% endif %}
diff --git a/_javascript/modules/components/mermaid.js b/_javascript/modules/components/mermaid.js
index 2b4759f4726..91df4f25497 100644
--- a/_javascript/modules/components/mermaid.js
+++ b/_javascript/modules/components/mermaid.js
@@ -11,7 +11,7 @@ function refreshTheme(event) {
     const mermaidList = document.getElementsByClassName(MERMAID);
 
     [...mermaidList].forEach((elem) => {
-      const svgCode = elem.previousSibling.children.item(0).innerHTML;
+      const svgCode = elem.previousSibling.children.item(0).textContent;
       elem.textContent = svgCode;
       elem.removeAttribute('data-processed');
     });
diff --git a/_sass/pages/_post.scss b/_sass/pages/_post.scss
index 9348c5669f8..9b8fa7e6d75 100644
--- a/_sass/pages/_post.scss
+++ b/_sass/pages/_post.scss
@@ -220,14 +220,11 @@ header {
 @-webkit-keyframes fade-up {
   from {
     opacity: 0;
-    position: relative;
-    top: 2rem;
+    margin-top: 4rem;
   }
 
   to {
     opacity: 1;
-    position: relative;
-    top: 0;
   }
 }
 
@@ -247,6 +244,7 @@ header {
 %top-cover {
   content: '';
   display: block;
+  position: -webkit-sticky;
   position: sticky;
   top: 0;
   width: 100%;
@@ -257,13 +255,16 @@ header {
 #toc-wrapper {
   top: 0;
   transition: top 0.2s ease-in-out;
-  -webkit-animation: fade-up 0.8s;
-  animation: fade-up 0.8s;
   overflow-y: auto;
   max-height: 100vh;
   scrollbar-width: none;
   margin-top: 2rem;
 
+  &:not(.invisible) {
+    -webkit-animation: fade-up 0.8s;
+    animation: fade-up 0.8s;
+  }
+
   ul {
     list-style: none;
     font-size: 0.85rem;
@@ -275,10 +276,6 @@ header {
         margin: 0.4rem 0;
       }
 
-      &:first-child {
-        margin-top: 0;
-      }
-
       a {
         padding: 0.2rem 0 0.2rem 1.25rem;
       }