Technically I fixed the dark mode

function.js

@@ -15,4 +15,21 @@ var checkbox = document.querySelector('input[name=mode]');
             window.setTimeout(() => {
                 document.documentElement.classList.remove('transition');
             }, 1000)
-        }
+        }
+
+        const btn = document.querySelector(".container_toggle");
+
+        const currentTheme = localStorage.getItem("theme");
+        if (currentTheme == "dark") {
+          document.body.classList.add("dark-theme");
+        }
+        
+        btn.addEventListener("click", function () {
+          document.body.classList.toggle("dark-theme");
+        
+          let theme = "light";
+          if (document.body.classList.contains("dark-theme")) {
+            theme = "dark";
+          }
+          localStorage.setItem("theme", theme);
+        });

index.html

@@ -49,5 +49,5 @@
             <input class="container_toggle" type="checkbox" id="switch" name="mode">
             <label for="switch">Toggle</label>
         </div>
-        <script  src="https://1elci.it/function.js"></script>
+        <script src="/function.js"></script>
 </body>