body {
    background-image: 
        linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.6)),
        url(/assets/background.png);
    background-position: center center;
    background-repeat: no-repeat;
    background-size: cover;
    background-attachment: fixed;
    min-height: 100vh;
    
    opacity: 1;
    transition: opacity 0.5s ease; 
}
@starting-style {
    body{
        opacity: 0;
    }
}