#main {
    background: #fff;
    border-left: 20px solid #eee;
    border-right: 20px solid #eee;
    margin: 0 auto;
    max-width: 800px;
    padding: 20px;
  }
  
  pre.listing {
    background: #eee;
    border: 1px solid #ccc;
    margin: .6em 0 .3em 0;
    padding: .1em .3em;
  }
  
  pre.listing b {
    color: #f00;
  }