html, body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    height: 100%;
    background: black;
    font-family: 'Segoe UI', sans-serif;
    color: white;
}

canvas {
    position: absolute;
    width: 100%;
    height: 100%;
    display: block;
}

.overlay {
    position: absolute;
    left: 50%;
    top: 80%; /* Đẩy xuống dưới để không che mặt trời */
    transform: translate(-50%, -50%);
    z-index: 10;
    text-align: center;
    background: rgba(0, 0, 0, 0.4);
    padding: 2rem;
    border-radius: 12px;
    backdrop-filter: blur(4px);
}

.title {
    font-size: 2.5rem;
    font-weight: bold;
    margin-bottom: 1rem;
    font-family: cursive;
    white-space: nowrap;
}

#clock {
    font-size: 2.2rem;
    font-weight: bold;
    letter-spacing: 3px;
    font-family: emoji;
    white-space: nowrap;
}

.game-link {
    position: fixed;
    top: 18px;
    right: 32px;
    z-index: 20;
    font-size: 1.1rem;
    font-weight: bold;
    color: #fff;
    background: #222b;
    padding: 10px 18px;
    border-radius: 8px;
    text-transform: uppercase;
    letter-spacing: 2px;
    text-decoration: none;
    box-shadow: 0 2px 8px #0006;
    border: 2px solid #fff3;
    transition: background 0.2s, color 0.2s;
}

.game-link:hover {
    background: #fff;
    color: #222;
    border-color: #fff;
}
@media (max-width: 600px) {
    .overlay {
    top: 88%;
    padding: 0.8rem 0.5rem;
    border-radius: 8px;
    min-width: 120px;
    max-width: 98vw;
    }
    .title {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    }
    #clock {
    font-size: 1.1rem;
    letter-spacing: 1px;
    }
    .game-link {
    font-size: 0.9rem;
    padding: 7px 10px;
    top: 8px;
    right: 8px;
    border-radius: 6px;
    }
}