#join-community-popup {
  z-index: 150;
  position: absolute;
  width: 500px;
  height: 180;
  right: 50px;
  top: 50px;
  background: white;
  border: 2px solid black;
  text-align: center;
  cursor: move;
}
#join-community-popup .button-bar {
  margin: 1em;
}
#join-community-popup .button-bar .button {
  float: none;
}