<div></div>
div{
    width:242px;
    height:242px;
    background:#f69;
    margin: 50px auto;
    -webkit-clip-path:polygon(29.34% 0%, 70.66% 0%,100% 29.34%,100% 70.66%,70.66% 100%,29.34% 100%,0% 70.66%,0% 29.34%);
 }

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.