body{ 
   background-color:#000000;  
   text-align:center;
}
#back{
   background-image:url("logo.jpg");
   margin:0 auto;
   width:750px;
   height:300px;
}
#link{
   position:relative;
   display:block;
   width:150px;
   height:35px;
   left:300px;
   top:230px;
}