_header.scss

.header {
    height: 100vh;
    max-height: 900px;
    background: url(../imgs/main.jpg) no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
    min-height: 750px;

    .overlay {
        height: 100%;
        background: rgba($gray-900, .85);
        display: -webkit-flex;
        display: -ms-flex;
        display: flex;
        align-items: center;
        justify-content: center;
        flex-direction: column;
    }

    &-title {
        font-size: 2.4rem;
        font-weight: bold;
        opacity: .8;
        color: $dark;
    }

    // header mini
    &-mini {
        min-height: 24rem;
        height: 24rem;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        text-align: center;
        padding: 1rem;
        background: lighten($primary, 25%) !important;
    }
}