<!DOCTYPE html>
<html>
<head>
<style> div { width: 10px; height: 10px; margin: 1em; } </style>
</head>
<body style="background: white; color: black;">
<div style="outline: 1px dotted black;"></div>
<div style="color: blue; outline: 1px solid blue;"></div>
<div style="color: rgba(0,255,0,0.5); outline: 1px dashed rgba(0,255,0,0.5);"></div>
</body>
</html>