body {background-color: #E3FFEB;}
#bandeau{position:static; background-color:#ADE5DD;  height:11em; padding:1em;} 
#bandeau #bndlogo, #bandeau #bndrond{float:left}
#bandeau #bndlogo, #bandeau #bndrond{height:80%; margin-bottom : 1em;}
#bandeau #bndrond{margin-left : 5em; margin-top:-0.4em;}
@media screen and (max-width: 640px) {
    #bandeau #bndlogo, #bandeau #bndrond{height:35%;}
    #bandeau #bndrond{margin-left : 1em; margin-top:-0.4em;}
}
#topmenu{clear: both; width:50%;} 
#topmenu ul {list-style : none; }
#topmenu li {float:left; margin-right:1.5em;}
#topmenu li a{text-decoration: none; color:black; padding:0.4em; font-family: arial, verdana, sans-serif;}
#topmenu li a:hover {background-color:#55AA55; color:white;}
@media screen and (max-width: 640px) {
    #topmenu {width:100%;}    
    #topmenu li {margin-top:1.5em;}
    #topmenu li a{font-size:1.5em;}
}
#boxlog {width:50%; margin-left:5em; margin-top:2em;}
#boxlog label, #boxlog #txt_utilisateur {font-size:1.5em;}
#boxlog label {margin-bottom:0.5em;}
#boxlog #txt_utilisateur, #boxlog #txt_motdepasse {margin-bottom:1em;font-size:1em; width:25em;}
#btn_login {font-size:1em; padding:0.2em; width:8em;}
@media screen and (max-width: 640px) {
    #boxlog {margin-left:1em;}
    #boxlog #txt_utilisateur, #boxlog #txt_motdepasse {width:13em; font-size:1.5em;} 
    #loginnovalid {margin-left:2em;}
    #btn_login {font-size:1.5em;}
}
footer {clear:both;height: 7em; background-color: #B4B4B6; margin-top : 2em;}
#box_contact {padding:1em; font-size:1.5em; text-align:center;}
#box_footleft, #box_footright {float:left; width:49%;}
#box_footleft {padding-left:1em;}
#box_footright {text-align:right;}
@media screen and (max-width: 640px) {
    footer {height: 9em;}
    #box_footleft, #box_footright {width:100%; font-size:1em; padding-left:1em;}
    #box_footright {text-align:left;}
}