body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background-color: black;
}

.range-slider {
  text-align: center;
}

.slider {
  -webkit-appearance: none;
  width: 80%;
  height: 10px;
  border-radius: 5px;
  background: #d3d3d3;
  outline: none;
  opacity: 0.7;
  transition: opacity 0.2s;
}

.slider:hover {
  opacity: 1;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}

.slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}