.box {
width: 100px;
height: 100px;
background:linear-gradient(to right,#191919 4px,transparent 4px, transparent 86px,#191919 86px,#191919 90px,transparent 0) 0 0/100px 90px no-repeat,
linear-gradient(to bottom,#191919 4px,transparent 4px, transparent 86px,#191919 86px,#191919 90px,transparent 0) 0 0/90px 100px no-repeat,
linear-gradient(to right,rgba(137, 137, 137, 0.48) 4px,transparent 4px, transparent 86px,rgba(137, 137, 137, 0.48) 86px,rgba(137, 137, 137, 0.48) 90px,transparent 0) 10px 10px/100px 90px no-repeat,
linear-gradient(to bottom,rgba(137, 137, 137, 0.48) 4px,transparent 4px, transparent 86px,rgba(137, 137, 137, 0.48) 86px,rgba(137, 137, 137, 0.48) 90px,transparent 0) 10px 10px/90px 100px no-repeat;
}
<div class="box">
</div>