html {
    min-width: 1000px;
}

body {
    background: url(Image-fond1.jpg) center fixed;
    background-size: cover;
}

header {
    height: 210px;
    border: 3px solid black;
    background: url(bandeau1web.jpg);
    background-repeat: no-repeat;
    background-color: black;
}

header nav a {
    font-size: 22px;
    color: #FF0000;
    text-decoration: none;
    font-weight: bold;
    margin-top: 15px;
}

.chat,
.list_left {
    float: left;
    background-color: lightgrey;
    width: 15%;
    min-width: 150px;
    text-align: center;
    border: 2px solid black;
    height: 250px;
    clear: left;
    margin-top: 1.3%;
    overflow: auto;
}

#menu {
    display: flex;
    justify-content: space-around;
}

a:hover {
    color: white;
    font-weight: bold;
    text-shadow: 0px 0px 1px white;
}

header form {
    text-align: right;
}

form {
    color: #FF0000;
    padding-right: 15px;
}

.mdp {
    margin-top: -0.5%;
}

.retourmenu {
    float: left;
    margin-top: 45px;
    margin-left: 42px;
    height: 75px;
    width: 385px;
}

nav ol {
    margin-top: 22px;
    text-align: left;
    line-height: 200%;
}

.bienvenue {
    color: red;
    font-size: 18px;
    text-align: right;
    padding-right: 90px;
    padding-top: 20px;
    padding-bottom: 10px;
}

.choice_button {
    float: right;
    margin-right: 12px;
}

.choice_button2 {
    float: right;
}

.btn-link {
    border: none;
    outline: none;
    background: none;
    cursor: pointer;
    color: #0000EE;
    padding: 0;
    text-decoration: underline;
    font-family: inherit;
    font-size: inherit;
}

li {
    text-align: left;
}