body {
height:720px;
	width:1280px; 
background-color:white;
 margin-left:auto;
   margin-right:auto;
padding:10px;
/*background: url(../ressources/filigramme_lycee2.png) ; */
background: url(../ressources/filigramme_lycee.png) no-repeat center fixed;
/*-webkit-background-size: cover; /* pour anciens Chrome et Safari
background-size: cover; /* version standardisée */
}
.jumbotron {
    padding: 10px 0
}