<div class="collapse_span"></div>
.collapse_span {
position: absolute;
bottom: 1px;
left: 50%;
width: 60px;
height: 12px;
cursor: pointer;
}
.collapse_span:before {
content: "";
position: absolute;
top: 0;
right: 0;
bottom: 0;
left: 0;
border: 1px solid rgba(12,131,242,0.5);
transform: perspective(1em) rotateX(15deg);
}
.collapse_span:after {
content: '';
position: absolute;
bottom: 0;
left: 50%;
transform: translateX(-50%);
border-left: 10px solid transparent;
border-bottom: 6px solid #409EFF;
border-top: 10px solid transparent;
border-right: 10px solid transparent;
}
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