<!DOCTYPE html>
<html lang="en-US">
<head>
<style>
#point:after{
content:"\021D5";
}
</style>
</head>
<body>
<p>Up Down Double Arrow using Hexa Decimal: ⇕</p>
<p>Up Down Double Arrow using HTML Code: ⇕</p>
<p>Up Down Double Arrow using HTML Entity: ⇕</p>
<p id="point">Up Down Double Arrow using CSS Entity: </p>
</body>
</html>