1 <!DOCTYPE html>
2 <html>
3 <head>
4 <meta charset="UTF-8">
5 <title>Document</title>
6 </head>
7 <style>
8 #demo{
9 width: 600px;
10 height: 600px;
11 }
12 </style>
13 <body>
14 <div id="demo"></div>
15 <script>
16 var div = document.getElementById("demo");
17 randomColor(div);
18 function randomColor(div) {
19 r = Math.ceil(Math.random()*255);
20 g = Math.ceil(Math.random()*255);
21 b = Math.ceil(Math.random()*255);
22 a = (Math.random()).toFixed(1);
23 div.style.background = "rgb(" + r + "," + g + "," + b + "," + a + ")";
24 }
25 </script>
26 </body>
27 </html>
