body {
    background: radial-gradient(circle, #fff 0%, #8dffe6 100%);
    width: 100vw;
    height: 100vh;
    height: 100dvh;
    margin: 0;
    padding: 0;
    overflow: hidden; 
}
canvas { display: block; }
#three-canvas {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1;
    cursor: grab;
}
#three-canvas:active {
    cursor: grabbing;
}
#intro-screen.fading {
    pointer-events: none;
}
#intro-screen {
    cursor: default;
    user-select: none;
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.75); 
    color: white;
    text-justify: center;
    font-family: monospace;
    font-size: 1.8em;
    z-index: 10; 
    cursor: pointer;
    transition: opacity 0.1s ease;
}