如何用CSS (带渐变)做一个向下的箭头？

<div class="arrow-down"></div>

.arrow-down {
  width: 0;
  height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-top: 10px solid #f00; /*箭头颜色，可以替换为渐变色值*/
  position: relative;
}

.arrow-down::before {
  content: "";
  position: absolute;
  top: -10px;
  left: -10px;
  width: 0;
  height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-bottom: 10px solid #f00; /*箭头颜色，可以替换为渐变色值*/
}