message: Updated: refactored the css.
diff: .Colorpicker__canvas {
  width: 100%;
  height: 120px;
  - border-radius: 2px 2px 0 0;
  background-color: #ddd;
  + border-radius: 2px 2px 0 0;
  }
  .Colorpicker__sliderOperation {
  }
  .Colorpicker__hueSlider > .Slider .Slider__rail {
  - background: linear-gradient(to right,
  - hsl(0, 100%, 50%) 0%,
  - hsl(30, 100%, 50%) 8.333%,
  - hsl(60, 100%, 50%) 16.666%,
  - hsl(90, 100%, 50%) 25%,
  - hsl(120, 100%, 50%) 33.333%,
  - hsl(150, 100%, 50%) 41.666%,
  - hsl(180, 100%, 50%) 50%,
  - hsl(210, 100%, 50%) 58.333%,
  - hsl(240, 100%, 50%) 66.666%,
  - hsl(270, 100%, 50%) 75%,
  - hsl(300, 100%, 50%) 83.333%,
  - hsl(330, 100%, 50%) 91.666%,
  - hsl(360, 100%, 50%) 100%
  - );
  + background: linear-gradient(to right, hsl(0, 100%, 50%) 0%, hsl(30, 100%, 50%) 8.333%, hsl(60, 100%, 50%) 16.666%, hsl(90, 100%, 50%) 25%, hsl(120, 100%, 50%) 33.333%, hsl(150, 100%, 50%) 41.666%, hsl(180, 100%, 50%) 50%, hsl(210, 100%, 50%) 58.333%, hsl(240, 100%, 50%) 66.666%, hsl(270, 100%, 50%) 75%, hsl(300, 100%, 50%) 83.333%, hsl(330, 100%, 50%) 91.666%, hsl(360, 100%, 50%) 100%);
  }
  +
  .Colorpicker__alphaSlider > .Slider .Slider__track,
  .Colorpicker__hueSlider > .Slider .Slider__track {
  background-color: transparent;
  