header {
    background-color: white;
    box-shadow: 0 0 12px rgba(0,0,0,.15);
    margin: 0 auto;
    left: 0;
    right: 0;
    padding: 0 2em 0 2em;
    top: 0;
    justify-content: center;
    align-items: stretch;
    font-weight: bold;
    display: flex;
    flex-wrap: wrap;
    z-index: 10;
}
@media screen and (min-width: 1296px) { header {
    width: 67.5%;
}}

header #logo {
    flex: 1 0 20%;
    padding-right: 2em;
    padding-left: 2em;
    margin: 1em 0 1em 0;
}

header #titre {
    flex: 1 0 20%;
    margin: 1em 0 1em 0;
}

header #titre p {
    position: relative;
    top: 52%;
    transform: translateY(-50%);
    margin: 0;
    font-size: x-large;
}

header #menu {
    flex: 1 0 50%;
    display: flex;
    align-items: baseline;
    vertical-align: middle;
    flex-wrap: wrap;
}

header #menu a {
    flex-grow: 1;
    flex-shrink: 0;
    margin: 8px 10px 0 10px;
    padding-bottom: 5px;
    text-align: center;
    align-self: flex-end;
}

header #menu a#active {
    border-bottom: 3px solid purple;
}

header #menu a:not(#active) {
    color: black;
}

header #menu a:not(#active):hover {
    color: purple;
    padding-bottom: 5px;
    border-bottom: 3px solid purple;
}