Tutorial Transparent Inside Border

Transparent Inside Border

.inner-border {
background: #000;
color: #fff;
margin: 50px;
padding: 15px;
position: relative;
}
.inner-border:before {
border: 5px solid #000;
content: "";
position: absolute;
top: -10px;
bottom: -10px;
left: -10px;
right: -10px;
}

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