body {
  margin: 0;
  overflow: hidden;
  background: black;
}

#video {
  position: absolute;
  top: 0;
  left: 0;
  width: 640px;
  height: 480px;
  object-fit: cover;
  transform: scaleX(-1); /* Flip video like a mirror */
  z-index: 1;
}

#fogCanvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 640px;
  height: 480px;
  z-index: 2;
  pointer-events: none;
}

#resetBtn {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 10;
  padding: 10px 20px;
  font-size: 16px;
  background-color: rgba(255,255,255,0.8);
  border: none;
  border-radius: 6px;
  cursor: pointer;
}