antd-mobile/2x/cjs/components/scroll-mask/scroll-mask.css

<img src="https://gw.alipayobjects.com/mdn/rms_ee68a8/afts/img/A*hjjDS5Yy-ooAAAAAAAAAAAAAARQnAQ" alt="logo" width="100%" />

.adm-scroll-mask {
  position: absolute;
  top: 0;
  bottom: 0;
  z-index: 1;
  width: 60px;
  height: 100%;
  pointer-events: none;
}

.adm-scroll-mask-left {
  left: 0;
  background: linear-gradient(to right, #fff, rgba(255, 255, 255, 0));
}

.adm-scroll-mask-right {
  right: 0;
  background: linear-gradient(to left, #fff, rgba(255, 255, 255, 0));
}