aliapp-demo/page/biz/components/collapse/index.acss

.a-collapse {
  border-top: 1px solid #ddd;
  background-color: #fff;
  color: #000;
}

.a-collapse-title,
.a-collapse-content {
  border-bottom: 1px solid #ddd;
}

.a-collapse-title {
  position: relative;
  height: 88rpx;
  line-height: 88rpx;
  padding: 0 60rpx 0 30rpx;
  font-size: 34rpx;
}

.a-collapse-title-arrow {
  position: absolute;
  top: 30rpx;
  right: 30rpx;
  width: 30rpx;
  height: 30rpx;
  background-image: url("data:image/svg+xml;charset=utf-8,<svg width='16' height='26' viewBox='0 0 16 26' xmlns='http://www.w3.org/2000/svg'><path d='M2 0L0 2l11.5 11L0 24l2 2 14-13z' fill='%23C7C7CC' fill-rule='evenodd'/></svg>");
  background-size: contain;
  background-repeat: no-repeat;
  background-position: 50% 50%;
  transform: rotate(90deg);
}
.a-collapse-title-arrow-up {
  transform: rotate(270deg);
}

.a-collapse-content {
  padding: 20rpx;
  font-size: 30rpx;
}