body{font-size:133%; width: 1200px; text-align: justify; margin-left:auto; margin-right: auto}

tr td a {
 display: inline;
 float: left;   
 width:225px;
 background-color:white;
 color:black;
 text-decoration:none;
 text-align:center;
 padding:5px;
 border:2px solid;
 /*pour avoir un effet "outset" avec IE :*/
 border-color:#DCDCDC #696969 #696969 #DCDCDC;
 }
tr td a:hover {
 background-color:#D3D3D3;
 border-color:#696969 #DCDCDC #DCDCDC #696969;
 }