diff --git a/packages/nuejs.org/docs/css/doc-navi.css b/packages/nuejs.org/docs/css/doc-navi.css
index 24b692fc..40a45530 100644
--- a/packages/nuejs.org/docs/css/doc-navi.css
+++ b/packages/nuejs.org/docs/css/doc-navi.css
@@ -55,7 +55,7 @@ aside:first-child nav {
 
 /* table of contents */
 .toc {
-  margin: 1.5em 0;
+  margin: 1.5em 0 2.5em;
 
   /* overlfow ellipsis */
   a {
@@ -111,7 +111,7 @@ aside:first-child nav {
   aside { height: calc(100vh - 2em) }
   h1 { margin-top: 0 }
 
-  body > header, body > nav, article + aside h3, .toc {
+  body > header, body > nav, article + aside h4, .toc {
     display: none
   }
 }
diff --git a/packages/nuemark/src/parse-inline.js b/packages/nuemark/src/parse-inline.js
index 3092c370..7e9b97e1 100644
--- a/packages/nuemark/src/parse-inline.js
+++ b/packages/nuemark/src/parse-inline.js
@@ -78,7 +78,7 @@ const PARSERS = [
       // parse tag
       const tag = parseTag(str.slice(1, i).trim())
       const { name } = tag
-      const is_footnote = name[0] == '^'
+      const is_footnote = name && name[0] == '^'
       const end = i + 1
 
       // footnote?
@@ -89,6 +89,8 @@ const PARSERS = [
 
       // normal tag
       if (name == '!' || isValidName(name)) return { is_tag: true, ...tag, end }
+      // span
+      if (!name) return { is_span: true, ...tag, end }
 
       return { text: c }
     }
diff --git a/packages/nuemark/src/render-inline.js b/packages/nuemark/src/render-inline.js
index c5597420..5a893159 100644
--- a/packages/nuemark/src/render-inline.js
+++ b/packages/nuemark/src/render-inline.js
@@ -8,6 +8,7 @@ export function renderToken(token, opts={}) {
   const { text } = token
 
   return text ? text :
+    token.is_span ? elem('span', token.attr, renderInline(token.data?._)) :
     token.is_format ? formatText(token, opts) :
     token.is_var ? renderVariable(token.name, data) :
     token.is_image ? renderImage(token) :