body {
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: burlywood;
    margin: 0;
    height: 100%;
    overflow: hidden;
}

main {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%; 
    height: 100dvh;
}

iframe {
    width: 100%; 
    height: 100%;
}