html,body {
  margin-top: 20px;
  text-align: center;
}
#main{
    margin:30px auto;
    padding:15px;
    border:0px solid;
    border-radius:5px;
    background:#6565;
}
img{
    max-width: 100%; 
    display: block; 
    height: auto;
    margin: auto;
  }
  #img-div{
    margin:-5px;
    margin-top:20px;
    width:100%;
    border:5px solid white;
    background:white;
  }
  #img-caption{
    margin:15px;
  }
  ul{
    max-width:550px;
    margin:0 auto;
    text-align:left;
  }
  li{
    margin: 10px;
  }
  a {
    text-decoration: none;
    color:blue;
  }