<!doctype html> | |
<title>CSS test reference</title> | |
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io"> | |
<style> | |
.test { | |
display: flex; | |
} | |
.test::before { | |
content: ""; | |
display: block; | |
width: 100px; | |
height: 100px; | |
background-color: green; | |
} | |
</style> | |
<div class="test"></div> |