diff --git a/onRenderBody.js b/onRenderBody.js
index d713b2f98b064..370709d6c1ceb 100644
--- a/onRenderBody.js
+++ b/onRenderBody.js
@@ -7,23 +7,31 @@ const themes = { light: lighttheme, dark: darktheme };
 const MagicScriptTag = (props) => {
   const codeToRunOnClient = `
       (function() {
+          // 1. Keeps SYSTEM as the priority preference
           const themeFromLocalStorage = localStorage.getItem('${DarkThemeKey}') || '${ThemeSetting.SYSTEM}';
-          const systemDarkModeSetting = () => window.matchMedia ? window.matchMedia('(prefers-color-scheme: dark)') : null;
-          const isDarkModeActive = () => {
-              return !!systemDarkModeSetting()?.matches;
+
+          // 2. We change the check to look for LIGHT mode explicitly
+          const systemLightModeSetting = () => window.matchMedia ? window.matchMedia('(prefers-color-scheme: light)') : null;
+          
+          const isLightModeActive = () => {
+              return !!systemLightModeSetting()?.matches;
           };
+
           let colorMode;
           switch (themeFromLocalStorage) {
               case '${ThemeSetting.SYSTEM}':
-                colorMode = isDarkModeActive() ? '${ThemeSetting.DARK}' : '${ThemeSetting.LIGHT}'
+                // LOGIC CHANGE: If Light is active -> Light. Otherwise (Dark, No Preference, or Error) -> Dark.
+                colorMode = isLightModeActive() ? '${ThemeSetting.LIGHT}' : '${ThemeSetting.DARK}'
                 break
               case '${ThemeSetting.DARK}':
               case '${ThemeSetting.LIGHT}':
                 colorMode = themeFromLocalStorage
                 break
               default:
-                  colorMode = '${ThemeSetting.LIGHT}'
+                  // 3. Fallback to DARK in case of error
+                  colorMode = '${ThemeSetting.DARK}'
             }
+
           const root = document.documentElement;
           const iterate = (obj) => {
             if (!obj) return;
@@ -46,4 +54,4 @@ const MagicScriptTag = (props) => {
 
 export const onRenderBody = ( { setPreBodyComponents }) => {
   setPreBodyComponents(<MagicScriptTag key="theme-injection" theme={themes} />);
-};
\ No newline at end of file
+};