diff --git a/app/layout.tsx b/app/layout.tsx
index 8410a5f..53a5897 100644
--- a/app/layout.tsx
+++ b/app/layout.tsx
@@ -53,7 +53,8 @@ export default async function RootLayout({
   children: React.ReactNode
 }) {
   const config = await getConfig()
-  const hasCustomFont = config.settings.advanced.customCSS.includes('font-family')
+  const customCSS = config.settings.advanced?.customCSS || ''
+  const hasCustomFont = typeof customCSS === 'string' ? customCSS.includes('font-family') : false
 
   if (config.settings.appearance.favicon) {
     metadata.icons = {
@@ -79,7 +80,7 @@ export default async function RootLayout({
   }
 
   return (
-    <html lang="en" data-theme={userTheme ?? config.settings.appearance.systemThemes} suppressHydrationWarning>
+    <html lang="en" data-theme={userTheme ?? config.settings.appearance.theme} suppressHydrationWarning>
       <head>
         <meta charSet="utf-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1" />
@@ -97,7 +98,7 @@ export default async function RootLayout({
           <ThemeProviderWrapper
             initialUserTheme={userTheme}
             initialUserColors={userCustomColors}
-            systemTheme={config.settings.appearance.systemThemes}
+            systemTheme={config.settings.appearance.theme}
             systemColors={config.settings.appearance.customColors}
           >
             <Snowfall />
diff --git a/packages/lib/config/index.ts b/packages/lib/config/index.ts
index 4e2c8a7..92201be 100644
--- a/packages/lib/config/index.ts
+++ b/packages/lib/config/index.ts
@@ -143,6 +143,7 @@ export const DEFAULT_CONFIG: EmberlyConfig = {
         input: '217.2 32.6% 17.5%',
         ring: '212.7 26.8% 83.9%',
       },
+      systemThemes: {},
     },
     advanced: {
       customCSS: '',
