Added chat tab on mobile layouts and other changes to mobile UI

web/components/video/player.scss

@@ -4,7 +4,7 @@
 }
 
 .vjs-owncast .vjs-big-play-button {
-  z-index: 999999;
+  z-index: 10;
   border-color: var(--primary-color) !important;
   border-radius: var(--theme-rounded-corners) !important;
 }
@@ -24,4 +24,4 @@
 }
 .vjs-quality-selector .vjs-icon-placeholder::before {
   content: "\f110";
-}
+}