diff --git a/webui2/src/components/code/file-viewer.tsx b/webui2/src/components/code/file-viewer.tsx
index 97bcb569b8af5fa6aacd3d42c2c02a71d607cc1a..85a6bf88224a75e1aba846d7691eb17c14f1911b 100644
--- a/webui2/src/components/code/file-viewer.tsx
+++ b/webui2/src/components/code/file-viewer.tsx
@@ -223,6 +223,7 @@ export function FileViewer({ blob }: FileViewerProps) {
       const hast = highlighter.codeToHast(blob.text!, {
         lang,
         themes: { light: "github-light", dark: "github-dark" },
+        defaultColor: false,
         transformers: [lineNumberTransformer()],
       });
 
diff --git a/webui2/src/index.css b/webui2/src/index.css
index 59bbe507ebaa52c527b87e3a181c185dd5b6bf7d..bad2964cb54d8729db450efbb063d965109ddeeb 100644
--- a/webui2/src/index.css
+++ b/webui2/src/index.css
@@ -111,13 +111,22 @@ body {
   color: var(--foreground);
 }
 
-/* ── Shiki dual-theme: swap to dark variables when .dark is active ───────── */
+/* ── Shiki dual-theme (defaultColor: false) ──────────────────────────────── */
+.shiki,
+.shiki span {
+  color: var(--shiki-light);
+  background-color: var(--shiki-light-bg);
+  font-style: var(--shiki-light-font-style);
+  font-weight: var(--shiki-light-font-weight);
+  text-decoration: var(--shiki-light-text-decoration);
+}
+
 .dark .shiki,
 .dark .shiki span {
-  color: var(--shiki-dark) !important;
-  background-color: var(--shiki-dark-bg) !important;
-  font-style: var(--shiki-dark-font-style) !important;
-  font-weight: var(--shiki-dark-font-weight) !important;
-  text-decoration: var(--shiki-dark-text-decoration) !important;
+  color: var(--shiki-dark);
+  background-color: var(--shiki-dark-bg);
+  font-style: var(--shiki-dark-font-style);
+  font-weight: var(--shiki-dark-font-weight);
+  text-decoration: var(--shiki-dark-text-decoration);
 }