diff --git a/src/markdown/markdown-render.css b/src/markdown/markdown-render.css
index b4bb50e..4bc0423 100644
--- a/src/markdown/markdown-render.css
+++ b/src/markdown/markdown-render.css
@@ -141,13 +141,6 @@
   overflow-wrap: anywhere;
 }
 
-.md-codeblock__label {
-  margin: 0 0 1rem;
-  font-family: var(--md-code-font);
-  font-size: 11px;
-  color: var(--subtle);
-}
-
 .md-inline-code {
   padding: 0.1em 0.24em;
   border-radius: 4px;
diff --git a/src/markdown/markdown.ts b/src/markdown/markdown.ts
index 2410f3a..52c7599 100644
--- a/src/markdown/markdown.ts
+++ b/src/markdown/markdown.ts
@@ -29,6 +29,7 @@ const alignmentClassFromToken = (token: any) => {
 const safeLink = (hrefRaw: string) => {
   const href = (hrefRaw || "").trim();
   if (!href) return "";
+  if (href.startsWith("//")) return "";
   if (/^(https?|mailto|tel):/i.test(href)) return href;
   if (/^[./#]/.test(href)) return href;
   if (!/^[a-z][a-z0-9+.-]*:/i.test(href)) return href;
@@ -255,11 +256,11 @@ markdown.renderer.rules.code_inline = (tokens: any[], idx: number) =>
 
 markdown.renderer.rules.fence = (tokens: any[], idx: number) => {
   const info = tokens[idx].info.trim();
-  const language = info || "code";
-  return `<pre class="md-codeblock"><code>${escapeHtml(tokens[idx].content).replace(
+  const languageClass = info.toLowerCase().replace(/[^a-z0-9_-]/g, "") || "code";
+  return `<pre class="md-codeblock"><code class="language-${languageClass}">${escapeHtml(tokens[idx].content).replace(
     /\n$/,
     ""
-  )}</code></pre><div class="md-codeblock__label">${escapeHtml(language)}</div>`;
+  )}</code></pre>`;
 };
 
 markdown.renderer.rules.code_block = (tokens: any[], idx: number) =>