try.css

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

html,
body {
    height: 100%;
    /* Ensure html and body cover the full height */
    width: 100%;
    overflow: hidden;
    /* Prevent scrollbars on the body */
    background-color: #111111;
    /* Set background on body */
}

canvas {
    display: block;
    /* Remove extra space below inline elements like canvas */
    width: 100%;
    /* Let canvas fill its container (body) */
    height: 100%;
    /* border: 1px solid red; /* Optional: for debugging */
}

/* Styles for the card (if you uncomment it in HTML) */
.card {
    position: absolute;
    /* Position relative to the nearest positioned ancestor (or body) */
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    /* Center the card */
    width: 20rem;
    height: 30rem;
    background: #31beff;
    z-index: 10;
    /* Ensure it's above the canvas */
    /* Add other card styles */
}