<ul class="cp_list">
  <li>css</li>
  <li>html</li>
  <li>copy</li>
  <li>easy</li>
</ul>

ul.cp_list {
  padding:0.5em;
  list-style-type:none;
}
ul.cp_list li {
  position:relative;
  padding: 0em 0.3em 0.3em 1.3em;
}
ul.cp_list li::before {
  position: absolute;
  content: '';
  display: block;
  top: 0.5em;
  left: 0;
  width: 6px;
  height: 6px;
  border-right: 3px solid #00BCD4;
  border-bottom: 3px solid #00BCD4;
  transform: rotate(-45deg);
}