diff --git a/CHANGELOG.md b/CHANGELOG.md
index af7d463..852debb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## master
 
+## 3.0.30 (2026-07-31)
+- C++29に対応
+
 ## 3.0.29 (2026-07-05)
 
 - 検索欄の autocapitalize を無効化
diff --git a/css/badge.scss b/css/badge.scss
index 0b27a7e..baa135c 100644
--- a/css/badge.scss
+++ b/css/badge.scss
@@ -166,6 +166,11 @@
       content: "C++26";
     }
   }
+  #{$sel}[data-cpp-version="29"] {
+    & a:before, & ~ #{$sel}.latest-spec:not(.noprefix) a:before {
+      content: "C++29";
+    }
+  }
 
   #{$sel}[data-named-version="future"] {
     & a:before, & ~ #{$sel}.latest-spec:not(.noprefix) a:before {