Fix mobile nav

Author: asauber

scss/components/Header.scss

@@ -5,4 +5,13 @@
         left: 0;
         z-index: 10;
     }
+
+    .MainHeader {
+        overflow: hidden;
+    }
+
+    .navbar-toggler {
+        position: fixed;
+        top: 0;
+    }
 }