Video background

    <div class="bg-video">
        <video class="bg-video__content" autoplay muted loop>
            <source src="img/video.mp4" type="video/mp4">
            <source src="img/video.webm" type="video/webm">
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        </video>
    </div>

Video background

    .bg-video {
        position: absolute;
        top     : 0;
        left    : 0;
        height  : 100%;
        width   : 100%;
        z-index : -1;
        opacity : 0.15;
        overflow: hidden;

        &__content {
            width     : 100%;
            height    : 100%;
            object-fit: cover;
        }
    }