Revert "add strict containment for container element"

This reverts commit 28c1008500.

scss/global.scss

@@ -16,7 +16,6 @@ body {
   overflow-y: auto;
   overflow-x: hidden;
   -webkit-overflow-scrolling: touch;
-  contain: strict;
   position: absolute;
   top: 72px;
   left: 0;