create an explosion

.container {
  width: 100px;
  height: 100px;
  background: #FFE000;
}

.explosion {
  width: 50px;
  height: 50px;
  background: #FF0000;
  position: absolute;
}

.explosion.top-left {
  top: 0;
  left: 0;
}

.explosion.top-right {
  top: 0;
  right: 0;
}

.explosion.bottom-left {
  bottom: 0;
  left: 0;
}

.explosion.bottom-right {
  bottom: 0;
  right: 0;
}