#entete
{
    position: fixed !important;
    opacity: 0.3;
    z-index: 1;
    height: 120px;
    background-color: black;
}
.navbar-toggle
{
    z-index: 1;
}
#div_logo
{
    position: fixed;
    margin-top: 23px;
    z-index: 1;
}
#espace
{
    margin-top: 40px;
    z-index: 1;
    position: fixed;
}
#logo
{
    height: 75px;
}
.SI
{
    font-size: 25px;
    color: white;
}
.menu
{
    z-index: 1;
    margin-top: 40px;
    position: fixed;
    background: none;
    border: none;
}
.men
{
    text-decoration: none !important;
    color: #ffd700;
    font-size: 15px;
}
.men:hover
{
    color: white;
}
.navbar-header
{
    margin-top: -35px;
}
.btn-reduire
{
    margin-top: 50px;
    margin-left: 15px;
}


@media screen and (max-width: 400px)
{
    #entete
    {
        height: 300px;
    }
    .SI
    {
        margin-left: 20px;
    }
    .men
    {
        display: block;
    }
    .menu
    {
        margin-top: 130px;
    }
}
@media screen and (min-width: 401px) and (max-width: 1267px)
{
    #entete
    {
        height: 300px;
    }
    .men
    {
        display: block;
    }
    .menu
    {
        margin-top: 130px;
        margin-left: 0px;
    }
}
@media screen and (min-width: 280px) and (max-width: 766px)
{
    #entete
    {
        height: 130px;
    }
    .menu
    {
        margin-top: 80px;
        margin-left: 60px;
    }
    #bs-example-navbar-collapse-1
    {
        background: #9e50bd;
    }
}
@media screen and (min-width: 767px) and (max-width: 992px)
{
    .menu
    {
        margin-top: 80px;
        margin-left: 60px;
    }
    #entete
    {
        height: 170px;
    }
}
@media screen and (min-width: 993px) and (max-width: 1268px)
{
    #entete
    {
        height: 130px;
    }
    .menu
    {
        margin-top: 80px;
        margin-left: 60px;
    }
}