refactor: update color modes handling

Author: mrholek

src/App.vue

@@ -15,8 +15,9 @@ export default {
 
     onBeforeMount(() => {
       const urlParams = new URLSearchParams(window.location.href.split('?')[1])
-      if (urlParams.get('theme')) {
-        setColorMode(urlParams.get('theme'))
+      const theme = urlParams.get('theme').match(/^[A-Za-z0-9\s]+/)[0]
+      if (theme) {
+        setColorMode(theme)
         return
       }