/* Reset and center */
body, html {
    margin: 0;
    padding: 0;
    background: #eaeaea;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    -webkit-touch-callout: none; /* iOS Safari */
    -webkit-user-select: none;
    -ms-user-select: none;
    user-select: none;
    touch-action: manipulation;
    font-family: Arial, sans-serif;
}

canvas {
    background: #87ceeb;
    border: 2px solid #444;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    max-width: 100vw;
    height: auto;
}