body {
    font-family: 'Montserrat', sans-serif;
    background: radial-gradient(circle at top left, #222, var(--background-color, #000))
                no-repeat fixed,
                linear-gradient(135deg, var(--background-color, #000), #111);
    background-blend-mode: overlay;
    color: var(--text-color, #fff);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    margin: 0;
    min-height: var(--app-height, 100vh);
    padding: calc(env(safe-area-inset-top) + 1rem) clamp(1rem, 4vw, 2rem) calc(env(safe-area-inset-bottom) + 2rem);
    box-sizing: border-box;
}

#game-title {
    margin-top: 20px;
    font-size: 2rem;
    text-shadow: 0 0 10px var(--theme-color, #00f);
}

#tetris {
    border: 2px solid var(--theme-color, #00f);
    background: #000;
    margin-top: 10px;
    border-radius: 4px;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.8), 0 0 10px var(--theme-color, #00f);
}

#game-wrapper {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    margin-top: 10px;
}

#sidebar {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    padding: 10px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.05);
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}

#next-title {
    margin: 0;
    font-size: 1.2rem;
}

#next-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
}

#next {
    border: 2px solid var(--theme-color, #00f);
    background: #000;
    width: 40px;
    height: 40px;
    margin-top: 5px;
    border-radius: 4px;
    box-shadow: 0 0 6px rgba(0, 0, 0, 0.5);
}

#score {
    margin-top: 10px;
    font-size: 1.2rem;
    font-weight: bold;
    padding: 4px 8px;
    background: rgba(0, 0, 0, 0.3);
    border-radius: 4px;
}

#controls {
    display: flex;
    flex-direction: column;
    gap: 5px;
    align-items: center;
}

.control-row {
    display: flex;
    gap: 5px;
}

#controls button {
    width: 40px;
    height: 40px;
    border: none;
    border-radius: 50%;
    background: linear-gradient(145deg, var(--theme-color, #00f), #0022ff);
    color: var(--background-color, #000);
    font-size: 1rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.5), inset 0 -2px 4px rgba(0, 0, 0, 0.3);
    cursor: pointer;
    transition: transform 0.1s, box-shadow 0.1s;
}

#controls button.wide {
    width: 100px;
    border-radius: 20px;
}

#controls button:hover {
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.6), 0 0 10px var(--theme-color, #00f);
}

#controls button:active {
    transform: scale(0.95);
}

footer {
    margin-top: auto;
    padding: 10px;
}

#game-container {
    position: relative;
    margin-top: 40px;
    padding: 20px;
    border-radius: 12px;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(8px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.6);
    display: flex;
    flex-direction: column;
    align-items: center;
}

#action-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 15px;
}

#controls .action-btn,
#action-buttons .action-btn {
    width: 80px;
    height: 35px;
    border-radius: 8px;
    font-size: 0.8rem;
    font-weight: bold;
}

#btn-start {
    background: linear-gradient(145deg, #28a745, #218838);
    color: #fff;
}

#btn-stop {
    background: linear-gradient(145deg, #dc3545, #c82333);
    color: #fff;
}

#btn-refresh {
    background: linear-gradient(145deg, #ffc107, #e0a800);
    color: #000;
}