css-缺角

.StatisticsPlan-item:before {
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 0 0 0.0290697674rem 0.0290697674rem;
  border-color: transparent transparent rgba(7, 248, 255, 0.3) transparent;
  position: absolute;
  bottom: 0px;
  right: -0.0029069767rem;
  content: "";
}