diff --git a/_layouts/default.html b/_layouts/default.html
index 8e523ff..ce6a5a0 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="{{ page.lang | default: "en" }}" class="html" data-theme="{{ site.theme_config.appearance | default: "auto" }}">
+<html lang="{{ page.lang | default: "en" }}" class="html" data-theme="{{ site.theme_config.appearance | default: "light" }}">
         {%- include head.html -%}
   <body>
     <main class="page-content" aria-label="Content">
