html {
    display: flex;
    height: 100vh;
    width: 100vw;
}

body {
    margin: 0;
    display: flex;
    width: 100%;
    padding: 10px;

    align-items: center;
    justify-content: center;
}

.videodiv {
    height: 300px;
    aspect-ratio: 16/9;
    display: flex;
    padding: 10px;

    border: 2pt dashed black;
}