.background-slider-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.background-slider .swiper-slide {
    background-size: cover;
    background-position: center;
    width: 100%;
    height: 100vh;
}