@media (max-width: 480px)
{
   div#contents
   {
       display:table;
       table-layout:fixed;
       width:100%;
   }
   div#menubar
   {
       display:table-footer-group;
       width:100%;
   }
   div#body
   {
       display:table-row-group;
       width:100%;
   }
}

@media (min-width: 481px)
{
   div#contents
   {
       display:table;
       table-layout:fixed;
       width:100%;
   }
   div#menubar
   {
       display:table-cell;
       vertical-align:top;
       width:120px;
   }
   div#body
   {
       display:table-cell;
   }
}