<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<div></div>
</body>
<style>
div{
width: 190px;
height: 190px;
background: #00ff00;
position: relative;
}
div:before,
div:after{
position: absolute;
content: "";
left: -5px;
right: -5px;
top: -5px;
bottom: -5px;
border: 5px solid #FF33FF;
}
div:before{
animation: move 5s linear infinite;
}
div:after{
border-color: #FF33FF;
animation: move 5s linear infinite normal -2.5s;
}
@keyframes move{
0%,100%{
clip: rect(0,200px,5px,0);
}
25%{
clip: rect(0,200px,200px,195px);
}
50%{
border-color: #00ff0088;
clip: rect(195px,200px,200px,0);
}
75%{
clip: rect(0,5px,200px,0px);
}
}
</style>
</html>
