update header styling, add searchbar and implement it on every page

webseite/assets/css/topic.css

@@ -28,7 +28,7 @@ body {
     left: 0;
     top: 0;
     transition: transform 0.3s ease;
-    z-index: 50;
+    z-index: 40;
 }
 
 .sidebar-header {
@@ -187,6 +187,16 @@ body {
         width: 100%;
         padding: 1rem;
     }
+
+    .menu-toggle {
+        display: flex !important;
+    }
+}
+
+@media (min-width: 1025px) {
+    .menu-toggle {
+        display: none;
+    }
 }
 
 /* Active nav link style */
@@ -209,12 +219,3 @@ body {
     left: 0;
     font-weight: bold;
 }
-
-.menu-toggle {
-    padding: 0.75rem;
-    border-radius: 10px;
-    cursor: pointer;
-    align-items: center;
-    justify-content: center;
-    transition: all 0.3s ease;
-}