hubl/src/scss/_chat.scss

sib-chat {
  //position: absolute;
  border: 5px dotted red;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
  display: none;
  min-height: 300px;
}

.chat-view {
  sib-chat {
    display: block;
  }
}