body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 'https://images.unsplash.com/photo-1542281286-9e0a16bb7366';
    background-size: cover;
    background-position: center;
    z-index: -1;
    filter: blur(4px);
}