Preview:
body{
    background-image: url(https://images.unsplash.com/photo-1518155317743-a8ff43ea6a5f?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=870&q=80);
    background-repeat: no-repeat;
    background-size: 100vw 100vh;
    width: 100vw;
}
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