#mainNav {z-index: 1;}

.sommaire .masthead {
    height: 100vh;
}
.article .masthead {
    height: auto;
    padding: 0;
}

@media (min-width: 576px) {
}
@media (min-width: 768px) {
}
@media (min-width: 992px) {
    .article .masthead {
        height: 25vh;
    }
}
@media (min-width: 1200px) {
}
@media (min-width: 1400px) {
}