/* ===== Floating Button ===== */
#tetris-open-btn {
    position: fixed;
    bottom: 28px;
    right: 28px;
    z-index: 99998;
    display: flex;
    align-items: center;
    gap: 8px;
    background: linear-gradient(135deg, #6c3de1, #a855f7);
    color: #fff;
    border: none;
    border-radius: 50px;
    padding: 12px 20px 12px 14px;
    font-size: 15px;
    font-weight: 700;
    font-family: 'Segoe UI', Arial, sans-serif;
    cursor: pointer;
    box-shadow: 0 4px 20px rgba(108, 61, 225, 0.55);
    transition: transform 0.18s ease, box-shadow 0.18s ease;
    letter-spacing: 0.5px;
}
#tetris-open-btn:hover {
    transform: translateY(-3px) scale(1.04);
    box-shadow: 0 8px 28px rgba(108, 61, 225, 0.7);
}
#tetris-open-btn:active {
    transform: scale(0.97);
}
#tetris-open-btn svg {
    flex-shrink: 0;
}

/* ===== Modal Backdrop ===== */
#tetris-modal {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 99999;
    background: rgba(5, 5, 20, 0.82);
    backdrop-filter: blur(6px);
    align-items: center;
    justify-content: center;
    padding: 16px;
}
#tetris-modal.tetris-modal-open {
    display: flex;
}

/* ===== Modal Window ===== */
#tetris-modal-inner {
    position: relative;
    background: #13131f;
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 16px;
    box-shadow: 0 24px 80px rgba(0,0,0,0.8);
    overflow: hidden;
    max-width: 460px;
    width: 100%;
    font-family: 'Segoe UI', Arial, sans-serif;
}

/* ===== Header ===== */
#tetris-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 16px;
    background: linear-gradient(135deg, #1a0a3a, #2d0a5a);
    border-bottom: 1px solid rgba(255,255,255,0.08);
}
#tetris-title {
    font-size: 18px;
    font-weight: 800;
    color: #e0aaff;
    letter-spacing: 1px;
}
#tetris-header-right {
    display: flex;
    align-items: center;
    gap: 14px;
}
#tetris-score-label {
    color: #ccc;
    font-size: 14px;
}
#tetris-score {
    color: #ffd700;
    font-size: 16px;
}
#tetris-close-btn {
    background: rgba(255,255,255,0.1);
    border: none;
    color: #fff;
    font-size: 22px;
    line-height: 1;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s;
}
#tetris-close-btn:hover {
    background: rgba(255,0,80,0.4);
}

/* ===== Body ===== */
#tetris-body {
    display: flex;
    gap: 0;
    padding: 16px;
    align-items: flex-start;
}

/* ===== Canvas ===== */
#tetris-canvas {
    display: block;
    border-radius: 8px;
    border: 1px solid rgba(255,255,255,0.1);
    flex-shrink: 0;
}
#tetris-next-canvas {
    display: block;
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.08);
}

/* ===== Sidebar ===== */
#tetris-sidebar {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding-left: 16px;
    min-width: 108px;
}

.tetris-panel {
    background: rgba(255,255,255,0.05);
    border-radius: 8px;
    padding: 8px 10px;
    border: 1px solid rgba(255,255,255,0.07);
}
.tetris-panel-title {
    font-size: 10px;
    color: #888;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 6px;
}
#tetris-level,
#tetris-lines {
    font-size: 24px;
    font-weight: 800;
    color: #e0aaff;
    text-align: center;
}

#tetris-controls-hint {
    font-size: 11px;
    color: #666;
    line-height: 1.7;
    background: rgba(255,255,255,0.03);
    border-radius: 8px;
    padding: 8px 10px;
    border: 1px solid rgba(255,255,255,0.05);
}
#tetris-controls-hint div::before {
    margin-right: 4px;
}

#tetris-start-btn {
    background: linear-gradient(135deg, #6c3de1, #a855f7);
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 10px 0;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    width: 100%;
    transition: opacity 0.15s, transform 0.15s;
    letter-spacing: 0.5px;
}
#tetris-start-btn:hover {
    opacity: 0.88;
    transform: translateY(-1px);
}

/* ===== Overlay (game over / pause / start) ===== */
#tetris-overlay {
    position: absolute;
    left: 16px;
    top: 58px; /* below header */
    width: 240px;
    height: 480px;
    background: rgba(10, 5, 25, 0.82);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    z-index: 10;
}
#tetris-overlay-text {
    color: #e0aaff;
    font-size: 18px;
    font-weight: 700;
    text-align: center;
    line-height: 1.6;
    text-shadow: 0 2px 12px rgba(168,85,247,0.8);
}
#tetris-overlay-text small {
    font-size: 13px;
    color: #aaa;
    font-weight: 400;
}

/* ===== Responsive ===== */
@media (max-width: 480px) {
    #tetris-modal-inner {
        max-width: 100%;
    }
    #tetris-open-btn span {
        display: none;
    }
    #tetris-open-btn {
        padding: 13px;
        border-radius: 50%;
    }
}