You can edit / change the code and click run button <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Background Properties</title> <style> body { padding-bottom: 100px; background: #2A2A2A; color: #FFF; text-shadow: 0 1px #000; font: 1.1em/1.5 sans-serif; } h2 { margin: 0; font-size: 2em; } .box { background-color: hsla(127,47%,38%, .8); box-sizing: border-box; margin: 20px auto; padding: 20px; width: 400px; height: 200px; } </style> <script>var clicky_site_ids = clicky_site_ids || []; clicky_site_ids.push(101319977);</script><script async src="//static.getclicky.com/js"></script> <div class="box"></div> <h2>CSS Backrgound Color Property with HSLA values</h2> <p>background-color: hsla(127,47%,38%, .8);</p>