チェックのアイコン

<span class="dli-check"></span>

.dli-check {
  display: inline-block;
  vertical-align: middle;
  color: #333;
  line-height: 1;
  width: 1em;
  height: 0.45em;
  border: 0.1em solid currentColor;
  border-top: 0;
  border-right: 0;
  box-sizing: border-box;
  transform: translateY(-25%) rotate(-45deg);
}