body {
margin:0;
background-color:#000000;
color:#FFFFFF;
font-family:Arial;
line-height:1.5;}

.container {
margin: 100px;}

.quatre20 {
width:100%;}

a {
text-decoration: none;
color:black;
background-color:white;
font-weight:bold;
border-radius:12px;
padding:0.25rem 0.6rem 0.25rem 0.6rem;
}

a:hover {
    text-decoration-style: double;
    background-color:black;
    color:white;
}