body {background-color:rgb(240,240,240);text-align:center;width:800px;margin:auto;}
header, section, article, nav, footer, hgroup {display:block;}
header h1 {border:5px outset silver;padding:5px;}
footer {border:3px outset silver;}
footer * {margin:0;padding:0;}
header h1{margin:0;padding:0;}
canvas {margin:auto;}
input[type=number] {width:50px;text-align:center;}
#mesures .longueur {font-weight:bold;color:blue;}
#mesures .surface {font-weight:bold;color:red;}
a {text-decoration:underline overline; font-weight:bold;}