html,body{height:100dvh;margin:0;padding:0}
body{display:flex;flex-direction:column;overflow:auto}
header,footer{position:sticky;z-index:10}
header{top:0}
footer{bottom:0}
main.thread,#thread,.thread,.chat-center{
  flex:1 1 auto;
  min-height:0;
  overflow-y:auto !important;
  -webkit-overflow-scrolling:touch;
  overscroll-behavior:contain;
}