Fix .slicknav_menu position to resolve navbar obscuring issue

- Changed .slicknav_menu from position: absolute to position: relative
- Added z-index: 1000 for proper layering
- This prevents the mobile menu from covering the main navbar

css/custom.css

@@ -843,7 +843,8 @@ header.main-header .header-sticky.active{
 }
 
 .slicknav_menu{
-    position: absolute;
+    position: relative;
+    z-index: 1000;
     width: 100%;
 	padding: 0;
 	background: var(--accent-color);