added themes

scripts/main_page.js

@@ -287,4 +287,24 @@ function getCookie(name) {
     }
 
     return null;
+}
+
+const toggle = document.getElementById("themeToggle");
+
+toggle.addEventListener("change", () => {
+    document.documentElement.classList.toggle("dark", toggle.checked);
+    if (toggle.checked) {
+        setCookie("theme", "dark", 60 * 60 * 24 * 7);
+    }
+    else {
+        setCookie("theme", "light", 60 * 60 * 24 * 7);
+    }
+
+});
+
+const theme = getCookie("theme");
+
+if (theme === "dark") {
+    document.documentElement.classList.add("dark");
+    toggle.checked = true;
 }