bugfix: chat z-index

src/page-group-chat.pug

-#group-chat.chat-view
+.chat-view
   sib-chat(
     data-authentication='login',
     data-auto-login='true',

src/page-member-chat.pug

-#member-chat.chat-view
+.chat-view
   sib-chat(
     data-authentication='login',
     data-auto-login='true',

src/styles/content.scss

@@ -93,6 +93,7 @@ sib-display-lookuplist {
 .chat-view {
   padding: 1em;
   position: relative;
+  z-index: 0;
   @extend %frame;
   height: 400px;
   height: calc(100vh - 143px - 3em);