html, body {
  margin: 0;
  padding: 0;
}
canvas {
  display: block;
}
#controls {
  position: fixed;
  bottom: 0px;
  left: 0px;
  display: flex;
  align-items: center;
  gap: 1rem;  background: rgba(0,0,0);
  padding: 0.5rem 1rem;
 width: 100%;
  color: #fff;
  border-top: 0.75px solid grey;
}

#controls label {
  font-family: Arial;

  font-size: 14px;
}

#controls input[type="range"] {
  -webkit-appearance: none;
  width: 120px;
  height: 6px;
  border-radius: 100px;
  background:  rgb(82, 82, 82);
  outline: none;
}
#controls input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 12px;
  height: 12px;
  border-radius: 100%;
  background: #fff;
  cursor: pointer;
}

/* hide button on desktop */
#shuffleBtn {
  position: fixed;
    display: inline-block;
    padding: 0px 5px;
    z-index: 999;
    bottom:10px;
    right:10px;
    font-size: 0.9rem;
  border: none;
  border-radius: 4px;
  background: rgb(82, 82, 82);
  color: #ffffff;
  
  cursor: pointer;
}



@media screen and (max-width: 640px) {
  #shuffleBtn {
    position: fixed;
    display: inline-block;
    font-size: 0.9rem;
    padding: 0px 5px;
    z-index: 999;
    bottom:10px;
    right:10px;
  
  }
  #controls {
    bottom: 0px; left: 4px;
    padding: 10px;
    gap: 10px;
  }

  #controls label {
    font-size: 0.9rem;   /* bigger text */
  }

  #controls input[type="range"] {
    width: 16vw;         /* span most of the screen */
    height: 6px;        /* thicker track for touch */
  }
  #controls input[type="range"]::-webkit-slider-thumb {
    width: 12px;         /* larger thumb for easy tapping */
    height: 12px;
  }
  /* And similarly for non-WebKit browsers: */
  #controls input[type="range"]::-moz-range-thumb {
    width: 12px;         /* larger thumb for easy tapping */
    height: 12px;
  }
}