body { margin: 0; overflow: hidden; background: #050505; }

/* Contenedor Biomecánico */
#ui {
    position: absolute;
    top: 20px;
    left: 20px;
    font-family: 'Geist Mono', 'Courier New', Courier, monospace;

    /* Fondo: Materia orgánica oscura */
    background: radial-gradient(circle at center, #1a1a1a 0%, #000 100%);

    padding: 20px;
    /* Simulación de borde óseo con relieve */
    border: 4px solid #3d352b;
    border-radius: 4px;
    box-shadow:
        0 0 30px rgba(0, 0, 0, 1),
        inset 0 0 20px #2a241d,
        0 0 10px rgba(74, 63, 53, 0.5);

    width: 140px;
    pointer-events: none;
    user-select: none;
    z-index: 1000;
}

#ui .title {
    color: #8c7e6d; /* Color hueso viejo */
    font-weight: bold;
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 18px;
    text-align: center;
    text-shadow: 2px 2px 4px #000;
    animation: flicker 4s infinite;
}

@keyframes flicker {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; color: #a63a26; }
    52% { opacity: 1; }
}

#ui .keys {
    display: grid;
    grid-template-columns: repeat(3, 42px);
    grid-template-rows: repeat(2, 42px);
    gap: 10px;
    justify-content: center;
}

/* Teclas: Estilo Vértebra / Fósil */
#ui .key {
    background: linear-gradient(145deg, #252525, #111);
    border: 2px solid #4a3f35;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    color: #555;
    box-shadow:
        inset 0 0 12px #000,
        2px 2px 5px rgba(0,0,0,0.9);
    transition: all 0.05s steps(2);
    /* Táctil: las teclas sí reciben toques aunque el panel #ui no */
    pointer-events: auto;
    cursor: pointer;
    touch-action: none;
}

/* Cuando la tecla está activa: Brillo de energía residual */
#ui .key.active {
    color: #ff4500; /* Naranja/Rojo industrial */
    background: #1a0800;
    border-color: #8b0000;
    box-shadow:
        0 0 15px rgba(255, 69, 0, 0.6),
        inset 0 0 8px #000;
    transform: scale(0.92);
}

#ui .key.up    { grid-column: 2; grid-row: 1; }
#ui .key.left  { grid-column: 1; grid-row: 2; }
#ui .key.down  { grid-column: 2; grid-row: 2; }
#ui .key.right { grid-column: 3; grid-row: 2; }

#ui .hint {
    margin-top: 15px;
    font-size: 8px;
    color: #8c7e6d;
    text-align: center;
    text-transform: uppercase;
    letter-spacing: 1px;
}

#admin-access {
    position: fixed;
    bottom: 22px;
    left: 22px;
    z-index: 1000;
    width: 46px;
    height: 46px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at center, #1a1a1a 0%, #000 100%);
    border: 2px solid #3d352b;
    border-radius: 6px;
    color: #8c7e6d;
    box-shadow: 0 0 20px rgba(0,0,0,0.9), inset 0 0 12px #1a1511;
    transition: all 0.25s;
}
#admin-access:hover {
    color: #c9a84c;
    border-color: rgba(201,168,76,0.5);
    box-shadow: 0 0 20px rgba(201,168,76,0.2), inset 0 0 12px #1a1511;
}

/* ── Responsive: pantallas táctiles / móviles ── */
@media (max-width: 768px) {
    #ui {
        top: 14px;
        left: 14px;
        width: 132px;
        padding: 14px;
    }
    #ui .keys {
        grid-template-columns: repeat(3, 38px);
        grid-template-rows: repeat(2, 38px);
        gap: 8px;
    }
}
@media (max-width: 480px) {
    /* En móvil, controles más grandes y centrados abajo para el pulgar */
    #ui {
        top: auto;
        bottom: 16px;
        left: 50%;
        transform: translateX(-50%);
        width: auto;
        padding: 14px 18px;
        background: radial-gradient(circle at center, rgba(26,26,26,0.92) 0%, rgba(0,0,0,0.92) 100%);
    }
    #ui .keys {
        grid-template-columns: repeat(3, 52px);
        grid-template-rows: repeat(2, 52px);
        gap: 8px;
    }
    #ui .key { font-size: 22px; }
    /* El cuadro de movimiento pasa abajo-centro → la llave de admin sube a
       arriba-izquierda para no estorbar (solo en esta situación). */
    #admin-access { top: 16px; bottom: auto; left: 16px; width: 42px; height: 42px; }
}