I use this one, I find it easy one the eyes.
Code:
body {
color: rgb(189,226,252);
background-color:rgb(80,80,80);
text-align:justify;
line-spacing:1.8;
margin-top:10px;
margin-bottom:4px;
margin-right:20px;
margin-left:20px;
text-indent:2em;
}
h1, h2, h3, h4, h5, h6 {
color:black;
text-align:center;
font-style:italic;
font-weight:bold;}