js拖动条

<div class="slider-container">
  <input type="range" min="0" max="100" value="50" class="slider">
  <span id="value">50</span>
</div>

.slider-container {
  width: 300px;
  margin: 20px auto;
}

.slider {
  -webkit-appearance: none;
  width: 100%;
  height: 15px;
  border-radius: 5px;
  background: #d3d3d3;
  outline: none;
  opacity: 0.7;
  -webkit-transition: .2s;
  transition: opacity .2s;
}

.slider:hover {
  opacity: 1;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 25px;
  height: 25px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}

.slider::-moz-range-thumb {
  width: 25px;
  height: 25px;
  border-radius: 50%;
  background: #4CAF50;
  cursor: pointer;
}

const slider = document.querySelector('.slider');
const valueDisplay = document.getElementById('value');

slider.addEventListener('input', function() {
  valueDisplay.textContent = this.value;
});