* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
   
}

body,html {
    width: 100%;
    height: 100%;
    background-color: rgb(234, 227, 227);
    color: white;
   font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;

}
main {
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}
.box {
    width: 100%;
    height: 100%;
    background: radial-gradient(150px at var(--x) var(--y), rgba(78, 63, 63, 0.033) 100px, rgba(0, 0, 0, 0.951) 150px);
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(255, 254, 254, 0.137);
    transition: background 0.1s;
    z-index: 1;
}
:root {
    --x: 50%;
    --y: 50%;
}
video{
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}