/* ============================================================
   style.css - リバーシゲーム スタイルシート
   ============================================================ */

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Outfit:wght@400;600;700;800&display=swap');

/* ============================================================
   CSS Variables
   ============================================================ */
:root {
    /* カラーパレット */
    --bg-primary: #0a0e17;
    --bg-secondary: #111827;
    --bg-card: rgba(17, 24, 39, 0.8);
    --bg-glass: rgba(255, 255, 255, 0.05);
    --bg-glass-hover: rgba(255, 255, 255, 0.08);

    --board-bg: #1a6b3c;
    --board-bg-dark: #145a30;
    --board-border: #0d3d1f;
    --board-line: rgba(0, 0, 0, 0.3);
    --cell-hover: rgba(255, 255, 255, 0.12);
    --cell-valid: rgba(124, 255, 178, 0.25);
    --cell-valid-pulse: rgba(124, 255, 178, 0.4);

    --text-primary: #f0f4f8;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;

    --accent-green: #10b981;
    --accent-emerald: #34d399;
    --accent-blue: #3b82f6;
    --accent-purple: #8b5cf6;
    --accent-amber: #f59e0b;
    --accent-red: #ef4444;

    --gradient-primary: linear-gradient(135deg, #10b981, #3b82f6);
    --gradient-gold: linear-gradient(135deg, #f59e0b, #f97316);
    --gradient-board: linear-gradient(135deg, #1a6b3c, #1e7a44);

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow-green: 0 0 20px rgba(16, 185, 129, 0.3);
    --shadow-glow-blue: 0 0 20px rgba(59, 130, 246, 0.3);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;

    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* セルサイズ */
    --cell-size: 80px;
    --piece-size: 70px;
}

/* ============================================================
   Reset & Base
   ============================================================ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    background-image:
        radial-gradient(ellipse at 20% 50%, rgba(16, 185, 129, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(59, 130, 246, 0.06) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 80%, rgba(139, 92, 246, 0.05) 0%, transparent 50%);
}

/* ============================================================
   Layout
   ============================================================ */
.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

/* ============================================================
   Header
   ============================================================ */
.header {
    text-align: center;
    padding: 20px 0;
    width: 100%;
}

.header h1 {
    font-family: 'Outfit', sans-serif;
    font-size: 2.8rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
    margin-bottom: 6px;
}

.header .subtitle {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 300;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* ============================================================
   Glass Panel (共通)
   ============================================================ */
.glass-panel {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow-md);
}

/* ============================================================
   Setup Panel (ゲーム設定)
   ============================================================ */
.setup-panel {
    width: 100%;
    max-width: 700px;
    animation: slideUp 0.5s ease;
}

.setup-panel h2 {
    font-family: 'Outfit', sans-serif;
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--accent-emerald);
}

/* モード選択 */
.mode-selector {
    display: flex;
    gap: 12px;
    margin-bottom: 24px;
    flex-wrap: wrap;
}

.mode-btn {
    flex: 1;
    min-width: 160px;
    padding: 16px 20px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-md);
    background: var(--bg-glass);
    color: var(--text-primary);
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-align: center;
}

.mode-btn:hover {
    border-color: var(--accent-green);
    background: var(--bg-glass-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow-green);
}

.mode-btn.active {
    border-color: var(--accent-green);
    background: rgba(16, 185, 129, 0.15);
    box-shadow: var(--shadow-glow-green);
}

.mode-btn .mode-icon {
    font-size: 1.8rem;
    display: block;
    margin-bottom: 8px;
}

.mode-btn .mode-label {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* オプション */
.options-group {
    margin-bottom: 20px;
    padding: 16px;
    border-radius: var(--radius-md);
    background: rgba(0, 0, 0, 0.2);
}

.options-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    font-weight: 500;
}

.options-group .option-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.options-group .option-row:last-child {
    margin-bottom: 0;
}

/* スライダー */
.level-slider {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: rgba(255, 255, 255, 0.1);
    outline: none;
    transition: background var(--transition-fast);
}

.level-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--accent-green);
    cursor: pointer;
    box-shadow: 0 0 8px rgba(16, 185, 129, 0.5);
    transition: transform var(--transition-fast);
}

.level-slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.level-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--accent-green);
    cursor: pointer;
    border: none;
    box-shadow: 0 0 8px rgba(16, 185, 129, 0.5);
}

.level-value {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--accent-emerald);
    min-width: 50px;
    text-align: center;
    font-family: 'Outfit', sans-serif;
}

/* 色選択 */
.color-selector {
    display: flex;
    gap: 12px;
}

.color-btn {
    flex: 1;
    padding: 12px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-md);
    background: var(--bg-glass);
    color: var(--text-primary);
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.color-btn:hover {
    border-color: var(--accent-green);
    background: var(--bg-glass-hover);
}

.color-btn.active {
    border-color: var(--accent-green);
    background: rgba(16, 185, 129, 0.15);
}

.color-btn .color-disc {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: inline-block;
}

.color-disc.black {
    background: #1a1a2e;
    border: 2px solid #333;
}

.color-disc.white {
    background: #f0f0f0;
    border: 2px solid #ccc;
}

/* スタートボタン */
.start-btn {
    width: 100%;
    padding: 16px;
    border: none;
    border-radius: var(--radius-md);
    background: var(--gradient-primary);
    color: white;
    font-family: 'Outfit', sans-serif;
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-normal);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    position: relative;
    overflow: hidden;
}

.start-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.start-btn:hover::before {
    left: 100%;
}

.start-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow-green), var(--shadow-glow-blue);
}

.start-btn:active {
    transform: translateY(0);
}

/* ============================================================
   Game Area (メインゲームエリア)
   ============================================================ */
.game-area {
    display: flex;
    gap: 24px;
    align-items: flex-start;
    justify-content: center;
    flex-wrap: wrap;
    width: 100%;
}

/* ============================================================
   Info Panel (情報パネル)
   ============================================================ */
.info-panel {
    width: 220px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.score-card {
    padding: 20px;
    text-align: center;
}

.score-card .score-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 8px;
}

.score-card .score-row {
    display: flex;
    justify-content: space-around;
    align-items: center;
    gap: 12px;
}

.score-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.score-item .disc-icon {
    width: 32px;
    height: 32px;
    border-radius: 50%;
}

.score-item .disc-icon.black-disc {
    background: #1a1a2e;
    border: 2px solid #444;
    box-shadow: inset 0 -2px 4px rgba(0, 0, 0, 0.5);
}

.score-item .disc-icon.white-disc {
    background: #f0f0f0;
    border: 2px solid #ddd;
    box-shadow: inset 0 -2px 4px rgba(0, 0, 0, 0.1);
}

.score-item .score-count {
    font-family: 'Outfit', sans-serif;
    font-size: 1.8rem;
    font-weight: 700;
}

.score-item .score-count.black-count {
    color: #a0aec0;
}

.score-item .score-count.white-count {
    color: #fff;
}

.score-vs {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 600;
}

/* ターン表示 */
.turn-indicator {
    padding: 16px;
    text-align: center;
}

.turn-indicator .turn-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 8px;
}

.turn-indicator .turn-text {
    font-family: 'Outfit', sans-serif;
    font-size: 1.1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.turn-disc {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    display: inline-block;
}

.turn-disc.black {
    background: #1a1a2e;
    border: 2px solid #444;
}

.turn-disc.white {
    background: #f0f0f0;
    border: 2px solid #ddd;
}

/* 思考中インジケーター */
.thinking-indicator {
    display: none;
    padding: 14px;
    text-align: center;
    animation: fadeIn 0.3s ease;
}

.thinking-indicator.active {
    display: block;
}

.thinking-dots {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin-top: 8px;
}

.thinking-dots span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent-green);
    animation: pulse 1.4s infinite ease-in-out;
}

.thinking-dots span:nth-child(2) {
    animation-delay: 0.2s;
}

.thinking-dots span:nth-child(3) {
    animation-delay: 0.4s;
}

/* 操作ボタン */
.action-buttons {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.action-btn {
    padding: 12px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    background: var(--bg-glass);
    color: var(--text-primary);
    font-family: 'Inter', sans-serif;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.action-btn:hover {
    background: var(--bg-glass-hover);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-1px);
}

.action-btn.primary {
    background: rgba(16, 185, 129, 0.15);
    border-color: var(--accent-green);
}

.action-btn.primary:hover {
    background: rgba(16, 185, 129, 0.25);
}

/* Sound toggle */
.sound-toggle {
    font-size: 0.8rem;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    cursor: pointer;
    padding: 8px;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.sound-toggle:hover {
    background: var(--bg-glass);
}

/* ============================================================
   Board (盤面)
   ============================================================ */
.board-wrapper {
    position: relative;
}

.board-container {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg), 0 0 60px rgba(26, 107, 60, 0.2);
}

.board {
    display: grid;
    grid-template-columns: repeat(8, var(--cell-size));
    grid-template-rows: repeat(8, var(--cell-size));
    background: var(--gradient-board);
    border: 4px solid var(--board-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.cell {
    width: var(--cell-size);
    height: var(--cell-size);
    border: 1px solid var(--board-line);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    position: relative;
    transition: background-color var(--transition-fast);
}

.cell:hover {
    background-color: var(--cell-hover);
}

.cell.valid-move {
    cursor: pointer;
}

.cell.valid-move::after {
    content: '';
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--cell-valid);
    position: absolute;
    animation: validPulse 2s infinite ease-in-out;
}

.cell:not(.valid-move) {
    cursor: default;
}

/* 駒 */
.cell .piece {
    width: var(--piece-size);
    height: var(--piece-size);
    position: absolute;
    z-index: 2;
    transition: opacity 0.3s ease;
}

.cell .piece.placing {
    animation: placeDisc 0.3s ease;
}

.cell .piece.flipping {
    animation: flipDisc 0.5s ease;
}

/* 座標表示 */
.board-coords {
    position: absolute;
    font-family: 'Inter', sans-serif;
    font-size: 0.7rem;
    color: rgba(255, 255, 255, 0.4);
    font-weight: 500;
}

.coords-top, .coords-bottom {
    display: flex;
    width: calc(var(--cell-size) * 8 + 8px);
    justify-content: space-around;
    padding: 0 4px;
}

.coords-top {
    top: -20px;
    left: 0;
}

.coords-bottom {
    bottom: -20px;
    left: 0;
}

.coords-left, .coords-right {
    display: flex;
    flex-direction: column;
    height: calc(var(--cell-size) * 8 + 8px);
    justify-content: space-around;
    padding: 4px 0;
}

.coords-left {
    left: -20px;
    top: 0;
}

.coords-right {
    right: -20px;
    top: 0;
}

/* ============================================================
   Game Result Modal
   ============================================================ */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn 0.3s ease;
}

.modal-overlay.active {
    display: flex;
}

.result-modal {
    background: var(--bg-secondary);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-xl);
    padding: 40px;
    text-align: center;
    max-width: 420px;
    width: 90%;
    animation: scaleIn 0.4s ease;
    box-shadow: var(--shadow-lg);
}

.result-modal .result-icon {
    font-size: 4rem;
    margin-bottom: 16px;
}

.result-modal .result-title {
    font-family: 'Outfit', sans-serif;
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 8px;
}

.result-modal .result-title.win {
    background: var(--gradient-gold);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.result-modal .result-title.lose {
    color: var(--accent-blue);
}

.result-modal .result-title.draw {
    color: var(--text-secondary);
}

.result-modal .result-score {
    font-size: 2.5rem;
    font-weight: 700;
    font-family: 'Outfit', sans-serif;
    margin: 16px 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

.result-modal .result-score .score-disc {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: inline-block;
}

.result-modal .result-detail {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.result-modal .result-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
}

.result-modal .result-actions button {
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
}

.result-modal .result-actions .btn-primary {
    background: var(--gradient-primary);
    color: white;
}

.result-modal .result-actions .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow-green);
}

.result-modal .result-actions .btn-secondary {
    background: var(--bg-glass);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.result-modal .result-actions .btn-secondary:hover {
    background: var(--bg-glass-hover);
}

/* ============================================================
   History Panel (対戦履歴)
   ============================================================ */
.history-panel {
    width: 100%;
    max-width: 700px;
}

.history-panel h3 {
    font-family: 'Outfit', sans-serif;
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--accent-emerald);
    display: flex;
    align-items: center;
    gap: 8px;
}

.history-list {
    max-height: 300px;
    overflow-y: auto;
    padding-right: 4px;
}

.history-list::-webkit-scrollbar {
    width: 4px;
}

.history-list::-webkit-scrollbar-track {
    background: transparent;
}

.history-list::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.15);
    border-radius: 2px;
}

.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    margin-bottom: 6px;
    background: rgba(0, 0, 0, 0.2);
    transition: background var(--transition-fast);
    font-size: 0.85rem;
}

.history-item:hover {
    background: rgba(0, 0, 0, 0.3);
}

.history-item .history-mode {
    font-weight: 600;
    min-width: 100px;
}

.history-item .history-result {
    font-weight: 600;
}

.history-item .history-result.win {
    color: var(--accent-green);
}

.history-item .history-result.lose {
    color: var(--accent-red);
}

.history-item .history-result.draw {
    color: var(--text-muted);
}

.history-item .history-score {
    color: var(--text-secondary);
    min-width: 70px;
    text-align: center;
}

.history-item .history-date {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.history-empty {
    text-align: center;
    padding: 30px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ============================================================
   Pass Notification
   ============================================================ */
.pass-notification {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-lg);
    padding: 24px 48px;
    font-family: 'Outfit', sans-serif;
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    z-index: 900;
    animation: passShow 1.5s ease forwards;
    pointer-events: none;
}

/* ============================================================
   Animations
   ============================================================ */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes placeDisc {
    0% {
        transform: scale(0);
        opacity: 0;
    }
    50% {
        transform: scale(1.15);
    }
    100% {
        transform: scale(1);
        opacity: 1;
    }
}

@keyframes flipDisc {
    0% {
        transform: rotateY(0deg);
    }
    50% {
        transform: rotateY(90deg);
    }
    100% {
        transform: rotateY(0deg);
    }
}

@keyframes validPulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.3);
        opacity: 0.8;
    }
}

@keyframes pulse {
    0%, 80%, 100% {
        transform: scale(0.6);
        opacity: 0.4;
    }
    40% {
        transform: scale(1);
        opacity: 1;
    }
}

@keyframes passShow {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.8);
    }
    15% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
    85% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
    100% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.8);
    }
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 900px) {
    .game-area {
        flex-direction: column;
        align-items: center;
    }

    .info-panel {
        width: 100%;
        max-width: 640px;
        flex-direction: row;
        flex-wrap: wrap;
    }

    .info-panel > * {
        flex: 1;
        min-width: 150px;
    }
}

@media (max-width: 680px) {
    :root {
        /* スマホ画面サイズに合わせて可変にする (8x8マス+枠線を考慮) */
        --cell-size: 11vw;
        --piece-size: 9.5vw;
    }

    .header h1 {
        font-size: 2rem;
    }

    .header .subtitle {
        font-size: 0.8rem;
    }

    .app-container {
        padding: 12px;
        gap: 16px;
    }

    .glass-panel {
        padding: 16px;
    }

    .mode-btn {
        min-width: 100%;
        padding: 12px;
    }

    .color-btn {
        flex-direction: column;
        gap: 4px;
        padding: 10px;
    }

    .start-btn {
        padding: 14px;
        font-size: 1.1rem;
    }
}

@media (max-width: 480px) {
    :root {
        --cell-size: 11.5vw;
        --piece-size: 10vw;
    }

    .info-panel {
        flex-direction: column;
        gap: 12px;
    }

    .info-panel > * {
        min-width: 100%;
    }

    .score-card .score-count {
        font-size: 1.5rem;
    }

    .result-modal {
        padding: 24px 16px;
    }

    .result-modal .result-title {
        font-size: 1.5rem;
    }

    .result-modal .result-score {
        font-size: 1.8rem;
    }

    .result-modal .result-actions {
        flex-direction: column;
    }

    .result-modal .result-actions button {
        width: 100%;
    }

    .board-coords {
        font-size: 0.6rem;
    }
}

/* ============================================================
   Utility: hidden class
   ============================================================ */
.hidden {
    display: none !important;
}