<div class="cross"></div>

　　

.cross {
  width: 64px;
  height: 64px;
  position: relative;
  background: #1c5fea;
  border-radius: 32px;
}
.cross:after {
  content: '';
  height: 4px;
  width: 24px;
  background: #fff;
  display: block;
  position: absolute;
  left: 20px;
  top: 30px;
  border-radius: 4px;
}
.cross:before {
  content: '';
  height: 24px;
  width: 4px;
  background: #fff;
  display: block;
  position: absolute;
  left: 30px;
  top: 20px;
  border-radius: 4px;
}