diff --git a/src/adventskalender.pug b/src/adventskalender.pug
index 1007229832f..f90052c15ec 100644
--- a/src/adventskalender.pug
+++ b/src/adventskalender.pug
@@ -36,6 +36,5 @@ html(lang="de")
         br
         = " für den schönen Baum! 🎄"
       a(href="/") Zurück zur Homepage
-    script(src=assetPath("/js/adventskalender.js"))
 
     include includes/_footer
diff --git a/src/css/base/variables.css b/src/css/base/variables.css
index 2c742936f83..9c3b47c89ff 100644
--- a/src/css/base/variables.css
+++ b/src/css/base/variables.css
@@ -83,7 +83,7 @@
 }
 
 @media (prefers-color-scheme: dark) {
-  :root:not([data-theme="light"]) {
+  :root:not([data-theme="light"]):not([data-theme="custom"]) {
     @mixin dark-theme;
   }
 }
diff --git a/static/js/adventskalender.js b/static/js/adventskalender.js
deleted file mode 100644
index e69de29bb2d..00000000000
diff --git a/static/js/main.js b/static/js/main.js
index 7d62ae50639..3f4dd74e46c 100644
--- a/static/js/main.js
+++ b/static/js/main.js
@@ -15,7 +15,9 @@ const setColorMode = mode => {
   }
 }
 
-setColorMode(initialColorMode)
+if (!document.documentElement.hasAttribute(THEME_ATTR)) {
+  setColorMode(initialColorMode)
+}
 
 const copyToClipboard = (e, text) => {
   if (navigator.clipboard) {