/**
 * Quantum Sudoku Styles
 * Sudoku with quantum superposition mechanics
 */

/* Quantum State Indicator */
.quantum-state {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    border: 2px solid #9b59b6;
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.quantum-icon {
    font-size: 1.5rem;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.7; transform: scale(1.1); }
}

#quantum-message {
    color: #bb86fc;
    font-size: 0.95rem;
}

/* Sudoku Board */
.sudoku-board {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    gap: 2px;
    background: var(--tertiary-bg);
    padding: 4px;
    border-radius: var(--radius-lg);
    border: 3px solid var(--primary-color);
    max-width: 450px;
    margin: 0 auto var(--spacing-lg);
    aspect-ratio: 1;
}

.sudoku-cell {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--secondary-bg);
    font-size: clamp(1rem, 4vw, 1.5rem);
    font-weight: bold;
    cursor: pointer;
    transition: all 0.2s;
    border: 1px solid var(--tertiary-bg);
    color: var(--text-primary);
    position: relative;
}

/* 3x3 Box Borders */
.sudoku-cell:nth-child(3n) {
    border-right: 2px solid var(--primary-color);
}

.sudoku-cell:nth-child(n+19):nth-child(-n+27),
.sudoku-cell:nth-child(n+46):nth-child(-n+54) {
    border-bottom: 2px solid var(--primary-color);
}

.sudoku-cell:hover {
    background: var(--tertiary-bg);
}

.sudoku-cell:focus {
    outline: 3px solid var(--accent-color);
    outline-offset: -3px;
    z-index: 1;
}

.sudoku-cell.selected {
    background: rgba(74, 144, 226, 0.3);
    border-color: var(--primary-color);
}

.sudoku-cell.fixed {
    color: var(--accent-color);
    font-weight: bold;
}

.sudoku-cell.error {
    background: rgba(231, 76, 60, 0.3);
    color: var(--loss-color);
}

.sudoku-cell.highlight {
    background: rgba(74, 144, 226, 0.15);
}

.sudoku-cell.correct {
    background: rgba(46, 204, 113, 0.2);
}

/* Quantum Cell Effect */
.sudoku-cell.quantum {
    background: linear-gradient(45deg, #9b59b6, #3498db);
    animation: quantumGlow 2s ease-in-out infinite;
}

.sudoku-cell.quantum::before {
    content: '?';
    position: absolute;
    font-size: 0.8rem;
    color: white;
    opacity: 0.7;
}

.sudoku-cell.quantum .superposition {
    font-size: 0.6rem;
    color: rgba(255, 255, 255, 0.8);
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1px;
}

@keyframes quantumGlow {
    0%, 100% { box-shadow: 0 0 5px #9b59b6; }
    50% { box-shadow: 0 0 15px #3498db; }
}

/* Number Pad */
.number-pad {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: var(--spacing-xs);
    max-width: 300px;
    margin: 0 auto var(--spacing-lg);
}

.num-btn {
    aspect-ratio: 1;
    font-size: 1.3rem;
    padding: var(--spacing-sm);
    background: var(--tertiary-bg);
    border: 2px solid var(--tertiary-bg);
    color: var(--text-primary);
}

.num-btn:hover,
.num-btn:focus {
    background: var(--primary-color);
    border-color: var(--primary-color);
}

.num-btn.active {
    background: var(--primary-color);
    border-color: var(--accent-color);
}

.erase-btn {
    background: var(--loss-color);
    border-color: var(--loss-color);
}

.erase-btn:hover {
    background: #c0392b;
}

/* Difficulty Selection */
.difficulty-select {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.difficulty-select label {
    display: block;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.diff-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
}

.diff-btn {
    padding: 8px 20px;
    font-size: 0.9rem;
    background: var(--tertiary-bg);
}

.diff-btn.active {
    background: var(--primary-color);
}

/* Timer and Stats */
.game-info {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--secondary-bg);
    border-radius: var(--radius-md);
}

.game-info > div {
    padding: var(--spacing-xs) var(--spacing-md);
}

#timer {
    font-family: monospace;
    font-size: 1.2rem;
    color: var(--accent-color);
}

/* Controls */
.controls {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
}

/* Instructions */
.instructions {
    background: var(--secondary-bg);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-top: var(--spacing-lg);
    border: 2px solid var(--primary-color);
}

.instructions h2 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
}

.instructions ul {
    list-style-position: inside;
    color: var(--text-secondary);
}

.instructions li {
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

/* Responsive */
@media (max-width: 500px) {
    .sudoku-board {
        max-width: 95vw;
    }
    
    .number-pad {
        max-width: 95%;
    }
    
    .num-btn {
        font-size: 1.1rem;
    }
}