* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
    touch-action: manipulation;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #e5e7eb;
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1600px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: #1f2937;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.7rem;
    margin-bottom: 10px;
    text-shadow: none;
    position: relative;
}

.version-tag {
    font-size: 0.675rem;
    color: #000;
    font-weight: 400;
    vertical-align: baseline;
    text-shadow: none;
    letter-spacing: 0.5px;
}

.subtitle {
    font-size: 1.08rem;
    opacity: 0.9;
}

.famous-game-title {
    font-size: 1rem;
    color: #4b5563;
    font-weight: 500;
    margin-top: 4px;
    display: none;
}

.game-container {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    justify-content: center;
}

.sidebar {
    flex: 0 0 300px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.sidebar-left {
    order: 1;
}

.sidebar-right {
    order: 3;
}

.board-container {
    order: 2;
}

.panel {
    background: white;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.panel h2 {
    color: #333;
    font-size: 1.08rem;
    margin-bottom: 15px;
    border-bottom: 2px solid #667eea;
    padding-bottom: 8px;
}

.panel-toggle {
    cursor: pointer;
    user-select: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.panel-arrow {
    font-size: 0.85rem;
    transition: transform 0.3s ease;
    display: inline-block;
    color: #6b9bda;
}

.panel-collapsible.collapsed .panel-arrow {
    transform: rotate(180deg);
}

.panel-collapsible .panel-body {
    overflow: hidden;
    max-height: 1200px;
    transition: max-height 0.35s ease, opacity 0.3s ease;
    opacity: 1;
}

.panel-collapsible.collapsed .panel-body {
    max-height: 0;
    opacity: 0;
}

.panel-collapsible.collapsed h2 {
    margin-bottom: 0;
    border-bottom: none;
    padding-bottom: 0;
}

.panel-collapsible > .btn {
    margin-top: 10px;
}

.config-section {
    margin-bottom: 20px;
}

/* Entrenador de aperturas */
.opening-training-info {
    background: #f0f4ff;
    border: 1px solid #c7d2fe;
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 10px;
}

.training-name {
    font-weight: 700;
    color: #4338ca;
    font-size: 0.85rem;
    margin-bottom: 4px;
}

.training-moves {
    font-family: 'Courier New', monospace;
    font-size: 0.76rem;
    color: #555;
    line-height: 1.4;
}

.training-desc {
    font-size: 0.74rem;
    color: #4b5563;
    line-height: 1.5;
    margin-top: 6px;
    padding-top: 6px;
    border-top: 1px solid #ddd6fe;
    font-style: italic;
}

.quiz-score {
    display: flex;
    gap: 16px;
    justify-content: center;
    padding: 8px;
    margin-top: 6px;
    background: #f3f4f6;
    border-radius: 8px;
    font-weight: 700;
    font-size: 0.95rem;
}

.quiz-correct {
    color: #16a34a;
}

.quiz-wrong {
    color: #dc2626;
}

.square.quiz-hint {
    box-shadow: inset 0 0 0 4px #f59e0b;
    animation: quizPulse 0.8s ease-in-out 3;
}

.square.quiz-correct-move {
    box-shadow: inset 0 0 0 4px #16a34a;
}

.square.quiz-wrong-move {
    box-shadow: inset 0 0 0 4px #dc2626;
}

@keyframes quizPulse {
    0%, 100% { box-shadow: inset 0 0 0 4px #f59e0b; }
    50% { box-shadow: inset 0 0 0 6px #f59e0b, 0 0 12px #f59e0b; }
}

.config-section label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 600;
}

.config-section input,
.select {
    width: 100%;
    padding: 8px;
    border: 2px solid #ddd;
    border-radius: 6px;
    font-size: 0.72rem;
    transition: border-color 0.3s;
}

.config-section input:focus,
.select:focus {
    outline: none;
    border-color: #667eea;
}

.info-text {
    font-size: 0.675rem;
    color: #888;
    margin-top: 5px;
}

.btn {
    width: 100%;
    padding: 12px;
    border: none;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    margin-top: 10px;
}

.btn-primary {
    background: #c7d2fe;
    color: #1f2937;
}

.btn-primary:hover {
    background: #a5b4fc;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.2);
}

.btn-success {
    background: #bbf7d0;
    color: #1f2937;
}

.btn-success:hover {
    background: #86efac;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(16, 185, 129, 0.2);
}

.btn-secondary {
    background: #e5e7eb;
    color: #1f2937;
}

.btn-secondary:hover {
    background: #d1d5db;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(107, 114, 128, 0.2);
}

.btn-danger {
    background: #fecaca;
    color: #1f2937;
}

.btn-danger:hover {
    background: #fca5a5;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(239, 68, 68, 0.2);
}

.btn-warning {
    background: #fed7aa;
    color: #1f2937;
}

.btn-warning:hover {
    background: #fdba74;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(245, 158, 11, 0.2);
}

.btn-info {
    background: #bae6fd;
    color: #1f2937;
}

.btn-info:hover {
    background: #7dd3fc;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(14, 165, 233, 0.2);
}

.btn-yellow {
    background: #fef08a;
    color: #1f2937;
}

.btn-yellow:hover:not(:disabled) {
    background: #fde047;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(234, 179, 8, 0.2);
}

.btn-orange {
    background: #fed7aa;
    color: #1f2937;
}

.btn-orange:hover:not(:disabled) {
    background: #fdba74;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(249, 115, 22, 0.2);
}

.btn:disabled {
    background: #e5e7eb;
    color: #9ca3af;
    cursor: not-allowed;
    transform: none;
}

.analysis-locked {
    background: #e5e7eb !important;
    color: #9ca3af !important;
    cursor: not-allowed !important;
    transform: none !important;
    opacity: 0.7;
    pointer-events: auto !important;
}

/* Estadísticas */
.stats-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 6px;
    margin-bottom: 12px;
}

.stat-item {
    background: #f9fafb;
    border-radius: 6px;
    padding: 8px 6px;
    text-align: center;
    border: 2px solid transparent;
    transition: all 0.3s;
}

.stat-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.stat-wins {
    border-color: #10b981;
}

.stat-wins .stat-value {
    color: #10b981;
}

.stat-draws {
    border-color: #f59e0b;
}

.stat-draws .stat-value {
    color: #f59e0b;
}

.stat-losses {
    border-color: #ef4444;
}

.stat-losses .stat-value {
    color: #ef4444;
}

.stat-label {
    font-size: 0.63rem;
    color: #666;
    font-weight: 600;
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stat-value {
    font-size: 1.17rem;
    font-weight: 700;
    font-family: 'Courier New', monospace;
}

.status p {
    margin-bottom: 10px;
    color: #555;
}

.status span {
    color: #667eea;
    font-weight: 600;
}

.captured-below {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 24px;
    margin-top: 8px;
    padding: 8px 12px;
    background: #f9fafb;
    border-radius: 6px;
    font-size: 0.95rem;
    color: #374151;
}

.captured-below span {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

#captured-white, #captured-black {
    font-weight: 500;
}

/* Historial de movimientos eliminado */

/* Botones de acción debajo del tablero (solo iconos) */
.board-action-buttons {
    display: flex;
    gap: 8px;
    justify-content: center;
    align-items: center;
    margin-top: 12px;
    flex-wrap: wrap;
    width: 100%;
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
}

.btn-icon {
    width: 44px;
    height: 44px;
    padding: 0;
    border: none;
    border-radius: 8px;
    font-size: 1.35rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon.btn-danger {
    background: #fecaca;
    color: #1f2937;
}

.btn-icon.btn-danger:hover:not(:disabled) {
    background: #fca5a5;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(239, 68, 68, 0.2);
}

.btn-icon.btn-warning {
    background: #fed7aa;
    color: #1f2937;
}

.btn-icon.btn-warning:hover:not(:disabled) {
    background: #fdba74;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(245, 158, 11, 0.2);
}

.btn-icon.btn-success {
    background: #bbf7d0;
    color: #1f2937;
}

.btn-icon.btn-success:hover:not(:disabled) {
    background: #86efac;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(16, 185, 129, 0.2);
}

.btn-icon.btn-primary {
    background: #c7d2fe;
    color: #1f2937;
}

.btn-icon.btn-primary:hover:not(:disabled) {
    background: #a5b4fc;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.2);
}

.btn-icon.btn-yellow {
    background: #fef08a;
    color: #1f2937;
}

.btn-icon.btn-yellow:hover:not(:disabled) {
    background: #fde047;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(234, 179, 8, 0.2);
}

.btn-icon.btn-orange {
    background: #fed7aa;
    color: #1f2937;
}

.btn-icon.btn-orange:hover:not(:disabled) {
    background: #fdba74;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(249, 115, 22, 0.2);
}

.btn-icon:disabled {
    background: #e5e7eb;
    color: #9ca3af;
    cursor: not-allowed;
    transform: none;
}

.btn-icon:focus {
    outline: 2px solid rgba(255, 255, 255, 0.5);
    outline-offset: 2px;
}

/* Barra de navegación de errores del análisis (justo debajo del tablero) */
.analysis-errors-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    padding: 10px 16px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    margin-top: 8px;
    max-width: 640px;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
}

.analysis-nav-btn {
    width: 40px;
    height: 40px;
    border: 2px solid #c7d2fe;
    background: #c7d2fe;
    color: #1f2937;
    border-radius: 8px;
    font-size: 1.5rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.analysis-nav-btn:hover:not(:disabled) {
    background: #a5b4fc;
    border-color: #a5b4fc;
    transform: scale(1.05);
}

.analysis-nav-btn:disabled {
    background: #e5e7eb;
    border-color: #e5e7eb;
    color: #9ca3af;
    cursor: not-allowed;
}

#analysis-nav-label {
    font-weight: 600;
    font-size: 0.95rem;
    min-width: 180px;
    text-align: center;
}

#analysis-nav-label.blunder {
    color: #dc2626;
}

#analysis-nav-label.imprecision {
    color: #ea580c;
}

.analysis-nav-list-btn {
    font-size: 1.1rem;
    margin-left: 8px;
}

/* Navegador de movimientos horizontal */
.move-navigator {
    display: flex;
    align-items: center;
    gap: 10px;
    background: white;
    padding: 12px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 640px;
    margin-top: 15px;
}

.nav-btn {
    background: #667eea;
    color: white;
    border: none;
    border-radius: 6px;
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.nav-btn:hover:not(:disabled) {
    background: #5568d3;
    transform: scale(1.05);
}

.nav-btn:disabled {
    background: #ddd;
    color: #999;
    cursor: not-allowed;
    transform: none;
}

.move-history-display {
    flex: 1;
    overflow-x: auto;
    overflow-y: hidden;
    white-space: nowrap;
    padding: 8px;
    background: #f9fafb;
    border-radius: 6px;
    font-family: 'Courier New', monospace;
    min-height: 40px;
    display: flex;
    align-items: center;
    gap: 4px;
}

.move-history-display::-webkit-scrollbar {
    height: 6px;
}

.move-history-display::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 3px;
}

.move-history-display::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 3px;
}

.move-history-display::-webkit-scrollbar-thumb:hover {
    background: #555;
}

.move-item {
    display: inline-block;
    padding: 6px 10px;
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    font-size: 0.81rem;
    cursor: pointer;
    transition: all 0.2s;
    margin: 0 2px;
}

.move-item:hover {
    background: #e8f0fe;
    border-color: #667eea;
    transform: translateY(-1px);
}

.move-item.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
    font-weight: 600;
}

.board-container {
    flex: 0 1 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    order: 2;
}

.board-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.board-with-coords {
    --sq: min(80px, calc((100vw - 80px) / 8));
    display: flex;
    align-items: center;
    gap: 8px;
}

.eval-bar-container {
    display: flex;
    align-items: center;
    height: calc(8 * var(--sq, 80px));
    padding: 4px 0;
}

.eval-bar-mobile {
    display: none;
}

.eval-bar {
    position: relative;
    width: 22px;
    height: 100%;
    background: #1a1a1a;
    border-radius: 4px;
    border: 2px solid #4a5568;
    overflow: hidden;
}

.eval-bar-fill {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 50%;
    background: #f0f0f0;
    transition: height 0.6s ease;
    border-radius: 0 0 2px 2px;
}

.eval-bar-label {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 0.63rem;
    font-weight: 700;
    color: #fff;
    text-shadow: 0 0 3px rgba(0,0,0,0.9), 0 0 6px rgba(0,0,0,0.7);
    z-index: 2;
    writing-mode: vertical-rl;
    text-orientation: mixed;
    white-space: nowrap;
    letter-spacing: 1px;
}

.rank-labels {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    height: calc(8 * var(--sq, 80px));
    padding: 4px 0;
}

.rank-label {
    height: var(--sq, 80px);
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: 2px;
    font-size: 0.99rem;
    font-weight: 700;
    color: #4b5563;
    min-width: 24px;
}

.board-and-files {
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
}

.file-labels {
    display: flex;
    justify-content: space-around;
    width: calc(8 * var(--sq, 80px));
    padding: 8px 0;
    gap: 0;
}

.file-label {
    width: var(--sq, 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.99rem;
    font-weight: 700;
    color: #4b5563;
}

.chess-board {
    display: grid;
    grid-template-columns: repeat(8, var(--sq));
    grid-template-rows: repeat(8, var(--sq));
    border: 4px solid #2d3748;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    background: white;
}

.board-banner {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    z-index: 50;
    text-align: center;
    font-weight: 800;
    font-size: 1.6rem;
    letter-spacing: 1px;
    padding: 10px 16px;
    pointer-events: none;
    animation: bannerSlideIn 0.35s ease-out;
    text-shadow: 0 1px 4px rgba(0,0,0,0.3);
}

.board-banner.banner-check {
    display: block;
    background: linear-gradient(135deg, rgba(234, 179, 8, 0.92), rgba(245, 158, 11, 0.92));
    color: #78350f;
    box-shadow: 0 4px 20px rgba(234, 179, 8, 0.5);
}

.board-banner.banner-checkmate {
    display: block;
    background: linear-gradient(135deg, rgba(220, 38, 38, 0.94), rgba(185, 28, 28, 0.94));
    color: #fff;
    box-shadow: 0 4px 20px rgba(220, 38, 38, 0.5);
    font-size: 1.8rem;
    pointer-events: auto;
    cursor: pointer;
}

.board-banner.banner-stalemate {
    display: block;
    background: linear-gradient(135deg, rgba(100, 116, 139, 0.92), rgba(71, 85, 105, 0.92));
    color: #fff;
    box-shadow: 0 4px 20px rgba(100, 116, 139, 0.5);
    pointer-events: auto;
    cursor: pointer;
}

@keyframes bannerSlideIn {
    from { opacity: 0; transform: translateY(-50%) scaleX(0.7); }
    to { opacity: 1; transform: translateY(-50%) scaleX(1); }
}

.square {
    width: var(--sq, 80px);
    height: var(--sq, 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    cursor: pointer;
    user-select: none;
    transition: all 0.3s ease-in-out;
    position: relative;
}

.square.last-move {
    background-color: rgba(255, 255, 0, 0.4) !important;
    box-shadow: inset 0 0 10px rgba(255, 255, 0, 0.6);
}

.square.variant-highlight {
    background-color: rgba(34, 197, 94, 0.5) !important;
    box-shadow: inset 0 0 12px rgba(34, 197, 94, 0.7);
}

.square.best-move {
    background-color: rgba(34, 197, 94, 0.5) !important;
    box-shadow: inset 0 0 10px rgba(34, 197, 94, 0.6);
}

.square-coordinate {
    position: absolute;
    top: 2px;
    right: 4px;
    font-size: 0.65rem;
    font-weight: 700;
    pointer-events: none;
    opacity: 0.7;
    font-family: monospace;
    color: #ffffff;
    text-shadow: 
        -1px -1px 1px rgba(0,0,0,0.8),
        1px -1px 1px rgba(0,0,0,0.8),
        -1px 1px 1px rgba(0,0,0,0.8),
        1px 1px 1px rgba(0,0,0,0.8);
}

.square.light {
    background: #f0d9b5;
}

.square.dark {
    background: #b58863;
}

.square.selected {
    background: #829769 !important;
    box-shadow: inset 0 0 10px rgba(0,0,0,0.3);
}

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

.square.valid-move::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background: rgba(0, 128, 0, 0.5);
    border-radius: 50%;
}

.square.valid-move.has-piece::after {
    width: 70px;
    height: 70px;
    background: none;
    border: 4px solid rgba(255, 0, 0, 0.6);
    border-radius: 50%;
}

.square:hover {
    filter: brightness(0.95);
}

.piece {
    font-size: 3rem;
    line-height: 1;
    pointer-events: none;
    transition: all 0.3s ease-in-out;
}

/* Estilo de piezas alfabético */
.piece-style-alpha .piece {
    font-size: 2.8rem;
    font-weight: 900;
    font-family: 'Georgia', serif;
}

.piece {
    font-size: 3rem;
    line-height: 1;
    pointer-events: none;
    transition: all 0.3s ease-in-out;
}

/* Piezas SVG */
.piece-svg {
    width: 85%;
    height: 85%;
    object-fit: contain;
    pointer-events: none;
    transition: all 0.3s ease-in-out;
}

/* Estilo de piezas alfabético */
.piece-style-alpha .piece {
    font-size: 2.8rem;
    font-weight: 900;
    font-family: 'Georgia', serif;
}

/* Colorear piezas blancas en estilo alpha */
.piece-style-alpha .piece[data-color="white"] {
    color: #ffffff;
    text-shadow: 
        -1px -1px 0 #000,
        1px -1px 0 #000,
        -1px 1px 0 #000,
        1px 1px 0 #000,
        0 2px 4px rgba(0,0,0,0.5);
}

/* Colorear piezas negras en estilo alpha */
.piece-style-alpha .piece[data-color="black"] {
    color: #1a1a1a;
    text-shadow: 
        -1px -1px 0 #fff,
        1px -1px 0 #fff,
        -1px 1px 0 #fff,
        1px 1px 0 #fff,
        0 2px 4px rgba(255,255,255,0.3);
}

/* Estilo de piezas moderno */
.piece-style-modern .piece {
    font-size: 2.8rem;
}

/* Estilo de piezas staunton (invertido) */
.piece-style-staunton .piece {
    font-size: 3rem;
}

.piece.moving {
    transform: scale(1.1);
    opacity: 0.7;
}

.piece-svg.moving {
    transform: scale(1.15);
    opacity: 0.7;
}

.drag-ghost {
    position: fixed;
    z-index: 9999;
    pointer-events: none;
    opacity: 0.9;
    filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.4));
    transform: scale(1.1);
    transition: none;
}

/* Contenedor de aperturas */
.opening-log {
    display: flex;
    flex-direction: column;
    gap: 2px;
    max-width: 640px;
    width: 100%;
}

.opening-entry {
    display: flex;
    align-items: center;
}

.opening-branch {
    color: #999;
    font-family: monospace;
    font-size: 0.75rem;
    white-space: pre;
    flex-shrink: 0;
}

.opening-banner {
    background: rgba(0, 0, 0, 0.75);
    color: #fff;
    text-align: left;
    padding: 4px 14px;
    border-radius: 6px;
    font-size: 0.765rem;
    font-weight: 500;
    letter-spacing: 0.3px;
    flex: 1;
    backdrop-filter: blur(4px);
}

.opening-entry.old .opening-banner {
    background: rgba(0, 0, 0, 0.35);
    font-size: 0.7rem;
    padding: 3px 12px;
}

.opening-entry.old .opening-branch {
    color: #bbb;
}

.opening-fade-in {
    animation: openingIn 0.4s ease forwards;
}

.opening-fade-out {
    animation: openingOut 0.6s ease forwards;
}

@keyframes openingIn {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: translateY(0); }
}

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

.opening-variants-btn {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: #fff;
    border: none;
    border-radius: 5px;
    padding: 2px 9px;
    font-size: 0.7rem;
    font-weight: 600;
    cursor: pointer;
    margin-left: 6px;
    white-space: nowrap;
    transition: opacity 0.2s;
}

.opening-variants-btn:hover {
    opacity: 0.85;
}

.opening-entry.old .opening-variants-btn {
    opacity: 0.5;
    font-size: 0.6rem;
    padding: 1px 6px;
}

.variants-popup {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 60;
    background: rgba(255, 255, 255, 0.55);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border-radius: 14px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    max-height: 70%;
    width: 85%;
    max-width: 380px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: variantsIn 0.25s ease-out;
}

@keyframes variantsIn {
    from { opacity: 0; transform: translate(-50%, -50%) scale(0.9); }
    to { opacity: 1; transform: translate(-50%, -50%) scale(1); }
}

.variants-popup-header {
    position: relative;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    padding: 10px 40px 10px 16px;
    background: rgba(229, 231, 235, 0.5);
    font-size: 0.85rem;
    font-weight: 600;
    color: #333;
    border-bottom: 2px solid #667eea;
}

.variants-popup-hint {
    width: 100%;
    font-size: 0.75rem;
    font-weight: 400;
    color: #667eea;
    margin-top: 4px;
    animation: pulse-hint 1.5s ease-in-out infinite;
}

@keyframes pulse-hint {
    0%, 100% { opacity: 0.7; }
    50% { opacity: 1; }
}

.variants-popup-close {
    position: absolute;
    top: 8px;
    right: 10px;
    cursor: pointer;
    font-size: 1rem;
    color: #888;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: color 0.2s, background 0.2s;
}

.variants-popup-close:hover {
    color: #333;
    background: rgba(0, 0, 0, 0.1);
}

.variants-popup-list {
    overflow-y: auto;
    padding: 4px 0;
}

.variants-popup-item {
    padding: 9px 16px;
    font-size: 0.82rem;
    color: #333;
    border-bottom: 1px solid #f0f0f0;
    display: flex;
    align-items: baseline;
    gap: 8px;
    transition: background 0.15s;
}

.variants-popup-item:last-child {
    border-bottom: none;
}

.variants-popup-item:hover {
    background: #f7f7ff;
}

.variant-move {
    color: #667eea;
    font-weight: 700;
    font-family: monospace;
    white-space: nowrap;
    min-width: 50px;
}

.variant-name {
    color: #555;
    font-weight: 400;
}

.known-variants-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.2s ease-out;
}

.known-variants-panel {
    background: #fff;
    border-radius: 14px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    max-height: 90vh;
    width: 95%;
    max-width: 960px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: variantsIn 0.25s ease-out;
}

.known-variants-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: #e5e7eb;
    font-size: 0.85rem;
    font-weight: 600;
    color: #333;
    border-bottom: 2px solid #667eea;
}

.known-variants-header .variants-popup-close {
    position: static;
    flex-shrink: 0;
    margin-left: 10px;
}

.known-variants-list {
    overflow-y: auto;
    padding: 8px 0;
    max-height: 60vh;
}

@media (max-width: 1024px) and (orientation: portrait), (max-width: 768px) {
    .known-variants-overlay {
        align-items: flex-end;
    }

    .known-variants-panel {
        border-radius: 14px 14px 0 0;
        max-height: 55vh;
        width: 100%;
        max-width: 100%;
    }

    .known-variants-list {
        max-height: 45vh;
    }
}

.known-variant-row {
    padding: 6px 16px;
    font-size: 0.8rem;
    font-family: monospace;
    display: flex;
    align-items: baseline;
    gap: 6px;
    border-bottom: 1px solid #f0f0f0;
}

.known-variant-row.current-line {
    background: #eef2ff;
    font-weight: 600;
}

.kv-indent {
    color: #ccc;
    white-space: pre;
}

.kv-move {
    color: #667eea;
    font-weight: 700;
    white-space: nowrap;
}

.kv-name {
    color: #555;
    font-weight: 400;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

.known-variant-row.current-line .kv-name {
    color: #333;
}

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

.thinking-indicator {
    background: white;
    padding: 20px 40px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    display: flex;
    align-items: center;
    gap: 15px;
}

/* Overlay de mensajes centrados */
.message-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    backdrop-filter: blur(4px);
    animation: fadeIn 0.3s ease;
}

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

.message-box {
    background: white;
    padding: 30px 50px;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    font-size: 1.35rem;
    font-weight: 600;
    text-align: center;
    max-width: 600px;
    animation: scaleIn 0.3s ease;
    position: relative;
}

.message-text {
    margin-bottom: 0;
}

.message-close-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background: none;
    border: none;
    font-size: 1.62rem;
    color: #999;
    cursor: pointer;
    width: 35px;
    height: 35px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.message-close-btn:hover {
    background: rgba(0, 0, 0, 0.1);
    color: #333;
}

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

.message-success {
    color: #10b981;
    border-left: 6px solid #10b981;
}

.message-error {
    color: #ef4444;
    border-left: 6px solid #ef4444;
}

.message-warning {
    color: #f59e0b;
    border-left: 6px solid #f59e0b;
}

.message-info {
    color: #3b82f6;
    border-left: 6px solid #3b82f6;
}

/* Overlay de análisis: ventana central */
.analysis-overlay {
    background: rgba(0, 0, 0, 0.5);
    align-items: center;
    justify-content: center;
}

/* Modal de análisis post-partida */
.analysis-modal {
    background: white;
    border-radius: 16px;
    padding: 24px;
    width: 440px;
    max-width: 95vw;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    animation: scaleIn 0.3s ease;
}

.analysis-title {
    font-size: 1.25rem;
    color: #333;
    margin-bottom: 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid #667eea;
    text-align: center;
}

.analysis-loading {
    padding: 28px 32px;
    text-align: center;
    color: #1f2937;
    font-size: 1.15rem;
    font-weight: 600;
}

.analysis-summary {
    margin-bottom: 16px;
    padding: 12px;
    background: #f9fafb;
    border-radius: 8px;
    font-size: 0.95rem;
}

.analysis-mistakes {
    margin-bottom: 16px;
    max-height: 300px;
    overflow-y: auto;
}

.analysis-move {
    padding: 10px 12px;
    margin-bottom: 6px;
    border-radius: 8px;
    font-size: 0.9rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 8px;
    transition: background 0.2s;
}

.analysis-move[data-move-index]:hover {
    filter: brightness(0.97);
}

.analysis-move.blunder {
    background: #fef2f2;
    border-left: 4px solid #ef4444;
}

.analysis-move.mistake {
    background: #fff7ed;
    border-left: 4px solid #f97316;
}

.analysis-move.inaccuracy {
    background: #fffbeb;
    border-left: 4px solid #eab308;
}

.analysis-move .move-num {
    font-weight: 700;
    color: #4b5563;
    min-width: 36px;
}

.analysis-move .move-text {
    flex: 1;
}

.analysis-move .best-move {
    font-size: 0.8rem;
    color: #059669;
    font-weight: 600;
}

@media (max-width: 1024px) and (orientation: portrait), (max-width: 768px) {
    .analysis-modal {
        width: 95%;
        max-width: 95%;
        padding: 18px;
    }
    .analysis-overlay.analysis-loading-mode .analysis-modal {
        min-width: 200px;
        padding: 14px;
    }
    .analysis-overlay.analysis-loading-mode .analysis-title {
        font-size: 0.75rem;
        margin-bottom: 8px;
    }
    .analysis-loading {
        padding: 12px 16px;
        font-size: 0.7rem;
    }
}

/* Overlay de promoción de peón */
.promotion-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9998;
}

.promotion-dialog {
    background: white;
    padding: 20px 24px;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.promotion-title {
    font-size: 1rem;
    color: #374151;
    margin-bottom: 12px;
    text-align: center;
}

.promotion-pieces {
    display: flex;
    gap: 12px;
    justify-content: center;
}

.promotion-piece-btn {
    width: 56px;
    height: 56px;
    font-size: 2.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #f3f4f6;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.promotion-piece-btn:hover {
    background: #667eea;
    border-color: #667eea;
    transform: scale(1.05);
}

/* Modal de lista de partidas */
.game-list-modal {
    background: white;
    border-radius: 16px;
    padding: 24px;
    max-width: 420px;
    width: 90%;
    max-height: 80vh;
    display: flex;
    flex-direction: column;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    animation: scaleIn 0.3s ease;
}

.game-list-title {
    font-size: 1.08rem;
    color: #333;
    margin-bottom: 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid #667eea;
    text-align: center;
}

.game-list {
    overflow-y: auto;
    max-height: 50vh;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.game-list-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 14px;
    background: #f9fafb;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.game-list-item:hover {
    background: #eef2ff;
    border-color: #667eea;
    transform: translateX(4px);
}

.game-list-name {
    flex: 1;
    font-weight: 600;
    color: #333;
    font-size: 0.855rem;
}

.game-list-info {
    font-size: 0.72rem;
    color: #888;
    white-space: nowrap;
}

.game-list-delete {
    background: none;
    border: none;
    color: #ccc;
    font-size: 0.99rem;
    cursor: pointer;
    padding: 2px 6px;
    border-radius: 4px;
    transition: all 0.2s;
    line-height: 1;
}

.game-list-delete:hover {
    color: #ef4444;
    background: rgba(239, 68, 68, 0.1);
}

.spinner {
    width: 30px;
    height: 30px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.thinking-indicator p {
    font-size: 0.99rem;
    color: #555;
    font-weight: 600;
}

/* Reloj de ajedrez */
.chess-clock {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.clock-controls {
    margin-top: 10px;
}

.clock-controls label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 600;
    font-size: 0.81rem;
}

.clock-controls select {
    width: 100%;
    cursor: pointer;
}

.clock-controls optgroup {
    font-weight: 600;
    font-style: normal;
}

.clock-player {
    flex: 1;
    background: #f0f0f0;
    border-radius: 8px;
    padding: 12px;
    text-align: center;
    border: 2px solid #ddd;
}

.clock-player.active {
    background: #667eea;
    border-color: #667eea;
}

.clock-player.active .clock-label {
    color: white;
}

.clock-player.active .clock-time {
    color: white;
}

.clock-label {
    font-size: 0.765rem;
    font-weight: 600;
    color: #666;
    margin-bottom: 5px;
}

.clock-time {
    font-size: 1.35rem;
    font-weight: 700;
    color: #333;
    font-family: monospace;
}

.clock-player.warning .clock-time {
    color: #f59e0b;
}

.clock-player.danger .clock-time {
    color: #ef4444;
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* Temas del tablero */
.board-theme-classic .square.light {
    background: #f0d9b5;
}

.board-theme-classic .square.dark {
    background: #b58863;
}

.board-theme-wood .square.light {
    background: #deb887;
}

.board-theme-wood .square.dark {
    background: #8b4513;
}

.board-theme-blue .square.light {
    background: #dee3e6;
}

.board-theme-blue .square.dark {
    background: #8ca2ad;
}

.board-theme-green .square.light {
    background: #ffffdd;
}

.board-theme-green .square.dark {
    background: #86a666;
}

.board-theme-gray .square.light {
    background: #e8e8e8;
}

.board-theme-gray .square.dark {
    background: #999999;
}

@media (max-width: 1400px) and (orientation: portrait) {
    .game-container {
        flex-direction: column;
        align-items: center;
    }
    
    .sidebar {
        flex: 1;
        width: 100%;
        max-width: 640px;
        margin: 0 auto;
        order: initial !important;
    }

    .sidebar-left {
        order: 1 !important;
    }

    .board-container {
        order: 2 !important;
        margin: 0 auto;
    }

    .sidebar-right {
        order: 3 !important;
    }
}

@media (max-width: 1400px) and (orientation: landscape) {
    .sidebar {
        flex: 0 0 220px;
    }

    .board-with-coords {
        --sq: min(60px, calc((100vh - 160px) / 8));
    }
}

/* Custom dropdown para responsive */
.custom-select-wrap {
    position: relative;
    width: 100%;
}

.custom-select-trigger {
    display: none;
    width: 100%;
    min-height: 48px;
    padding: 12px 40px 12px 14px;
    background: #fff;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 0.95rem;
    text-align: left;
    cursor: pointer;
    position: relative;
}

.custom-select-trigger::after {
    content: '▼';
    position: absolute;
    right: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 0.7rem;
    color: #6b7280;
}

.custom-select-trigger.open::after {
    transform: translateY(-50%) rotate(180deg);
}

.custom-select-list {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    max-height: 280px;
    overflow-y: auto;
    background: #fff;
    border: 2px solid #667eea;
    border-radius: 8px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.15);
    z-index: 1000;
    margin-top: 4px;
}

.custom-select-list.open {
    display: block;
}

.custom-select-optgroup {
    padding: 8px 12px 4px;
    font-size: 0.75rem;
    font-weight: 700;
    color: #667eea;
    background: #f5f3ff;
}

.custom-select-option {
    padding: 14px 16px;
    font-size: 0.95rem;
    cursor: pointer;
    border-bottom: 1px solid #f3f4f6;
    transition: background 0.15s;
}

.custom-select-option:last-child {
    border-bottom: none;
}

.custom-select-option:hover,
.custom-select-option:focus {
    background: #eef2ff;
}

.custom-select-option.selected {
    background: #ddd6fe;
    font-weight: 600;
}

@media (max-width: 1024px) and (orientation: portrait), (max-width: 768px) {
    .custom-select-wrap .select {
        position: absolute;
        opacity: 0;
        pointer-events: none;
        width: 100%;
        height: 48px;
    }

    .custom-select-wrap .custom-select-trigger {
        display: block;
    }
}

@media (min-width: 1025px), ((min-width: 769px) and (orientation: landscape)) {
    .custom-select-wrap .custom-select-trigger,
    .custom-select-wrap .custom-select-list {
        display: none !important;
    }

    .custom-select-wrap .select {
        position: static;
        opacity: 1;
        pointer-events: auto;
    }
}

@media (max-width: 1200px) {
    .board-with-coords {
        --sq: min(60px, calc((100vw - 80px) / 8));
    }
    
    .square {
        font-size: 2.5rem;
    }
    
    .rank-label {
        font-size: 0.9rem;
    }
    
    .file-label {
        font-size: 0.9rem;
    }
    
    /* Mensajes responsive */
    .message-box {
        padding: 25px 40px;
        font-size: 1.17rem;
        max-width: 500px;
        margin: 0 20px;
    }
}

/* Overlay: solo vertical en responsive */
.rotate-device-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: #1f2937;
    z-index: 10000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.rotate-device-message {
    text-align: center;
    color: white;
}

.rotate-device-message .rotate-icon {
    font-size: 4rem;
    display: block;
    margin-bottom: 20px;
    animation: rotateHint 2s ease-in-out infinite;
}

@keyframes rotateHint {
    0%, 100% { -webkit-transform: rotate(-30deg); transform: rotate(-30deg); }
    50% { -webkit-transform: rotate(30deg); transform: rotate(30deg); }
}

.rotate-device-message p {
    font-size: 1.25rem;
    font-weight: 600;
}

/* En landscape con pantalla pequeña: mostrar overlay y ocultar contenido */
@media (orientation: landscape) and (max-height: 600px) {
    .container,
    .app-footer {
        display: none !important;
    }

    .rotate-device-overlay {
        display: flex !important;
        padding-left: env(safe-area-inset-left);
        padding-right: env(safe-area-inset-right);
    }
}

/* Media query para smartphone horizontal (landscape) - usar visualización desktop */
@media (max-height: 700px) and (orientation: landscape) and (min-width: 600px) {
    body {
        padding: 10px;
    }

    header h1 {
        font-size: 1.62rem;
        margin-bottom: 5px;
    }

    .subtitle {
        font-size: 0.81rem;
    }

    header {
        margin-bottom: 15px;
    }

    /* Mantener layout desktop de 3 columnas */
    .game-container {
        display: flex;
        flex-direction: row;
        gap: 15px;
        align-items: flex-start;
        justify-content: center;
    }

    .sidebar {
        flex: 0 0 220px;
        order: initial;
    }

    .sidebar-left {
        order: 1;
    }

    .board-container {
        order: 2;
    }

    .sidebar-right {
        order: 3;
    }

    /* Tablero tamaño medio */
    .board-with-coords {
        --sq: min(50px, calc((100vh - 160px) / 8));
    }

    .square {
        font-size: 2.2rem;
    }
    
    .rank-label {
        font-size: 0.85rem;
    }
    
    .file-label {
        font-size: 0.85rem;
    }

    /* Paneles más compactos */
    .panel {
        padding: 12px;
    }

    .panel h2 {
        font-size: 0.9rem;
        margin-bottom: 10px;
    }

    .config-section {
        margin-bottom: 12px;
    }

    .btn {
        padding: 8px;
        font-size: 0.765rem;
        margin-top: 6px;
    }

    /* Navegador de movimientos compacto */
    .move-navigator {
        padding: 8px;
        gap: 6px;
        max-width: 400px;
    }
    
    .nav-btn {
        width: 32px;
        height: 32px;
        font-size: 1rem;
    }
    
    .move-item {
        font-size: 0.8rem;
        padding: 4px 8px;
    }

    /* Reloj compacto */
    .clock-time {
        font-size: 1.08rem;
    }

    .clock-player {
        padding: 8px;
    }

    .clock-label {
        font-size: 0.675rem;
    }
    
    /* Estadísticas compactas */
    .stat-value {
        font-size: 1.35rem;
    }
    
    .stat-label {
        font-size: 0.675rem;
    }
}

/* Footer */
.app-footer {
    text-align: center;
    padding: 20px;
    margin-top: 30px;
    font-size: 0.72rem;
    opacity: 0.6;
}

.app-footer a {
    color: #4b5563;
    text-decoration: none;
}

.app-footer a:hover {
    opacity: 1;
    text-decoration: underline;
}

/* Media query para smartphone y tablet en vertical (portrait) */
@media (max-width: 1024px) and (orientation: portrait) {
    header h1 {
        font-size: 2rem;
    }

    body {
        padding: 10px;
        font-size: 1rem;
    }
    
    .game-container {
        flex-direction: column;
        gap: 15px;
    }

    .panel h2 {
        font-size: 1.15rem;
    }
    
    .board-action-buttons {
        max-width: calc(8 * var(--square-size) + 28px);
        width: 100%;
        margin-top: 8px;
        gap: 6px;
    }

    .btn-icon {
        width: 44px;
        height: 44px;
        font-size: 1.35rem;
        border-radius: 10px;
    }

    .move-navigator {
        padding: 8px 6px;
        gap: 6px;
        max-width: calc(8 * var(--square-size) + 28px);
        width: 100%;
        margin-top: 6px;
    }
    
    .nav-btn {
        width: 40px;
        height: 40px;
        min-width: 40px;
        font-size: 1.2rem;
    }
    
    .move-history-display {
        flex: 1;
        min-width: 0;
    }

    .move-item {
        font-size: 0.88rem;
        padding: 6px 8px;
    }
    
    .message-box {
        padding: 22px 32px;
        font-size: 1.08rem;
        max-width: 90%;
        margin: 0 10px;
    }
    
    .message-close-btn {
        font-size: 1.5rem;
        width: 34px;
        height: 34px;
    }

    /* Orden específico para móviles */
    .board-container {
        order: 1 !important;
        width: 100%;
        gap: 8px;
        --square-size: min(80px, calc((100vw - 60px) / 8));
    }

    .chess-board {
        --sq: var(--square-size);
    }

    #clock-panel {
        order: 3 !important;
    }

    .sidebar-left .panel:nth-child(1) {
        order: 4 !important;
    }

    .sidebar-left .panel:nth-child(2) {
        order: 5 !important;
    }

    .sidebar-left .panel:nth-child(3) {
        order: 6 !important;  /* Partidas Famosas debajo de Entrenar Aperturas */
    }

    .sidebar-right .panel:nth-child(2) {
        order: 7 !important;
    }
    
    .sidebar-right .panel:nth-child(3) {
        order: 8 !important;
    }

    /* Piezas capturadas debajo del control de movimientos */
    .captured-below {
        font-size: 0.88rem;
        padding: 6px 10px;
    }

    /* Indicadores de movimiento proporcionales */
    .square.valid-move:not(.has-piece)::after {
        width: calc(var(--square-size) * 0.25);
        height: calc(var(--square-size) * 0.25);
    }

    .square.valid-move.has-piece::after {
        width: calc(var(--square-size) * 0.8);
        height: calc(var(--square-size) * 0.8);
        border-width: 2px;
    }

    /* Estadísticas compactas en móvil */
    .stats-container {
        gap: 8px;
    }
    
    .stat-item {
        padding: 12px 8px;
    }
    
    .stat-value {
        font-size: 1.55rem;
    }
    
    .stat-label {
        font-size: 0.78rem;
    }

    .config-section label {
        font-size: 0.92rem;
    }

    .select {
        font-size: 0.95rem;
    }

    #famous-game-select {
        size: 12;
        height: auto;
        min-height: 250px;
        overflow-y: auto;
    }

    #famous-panel .panel-body {
        overflow: visible;
    }

    /* Reorganizar todos los paneles en una columna */
    .sidebar,
    .sidebar-left,
    .sidebar-right {
        width: 100%;
        max-width: 100%;
        flex: 1 1 auto;
        display: contents;
    }

    .panel {
        width: 100%;
        margin: 0 auto;
        max-width: 100%;
    }

    /* Tablero dinámico al ancho del dispositivo */
    .board-with-coords {
        width: 100%;
        max-width: calc(8 * var(--square-size) + 28px + 8px);
        margin: 0 auto;
    }
    
    .chess-board {
        grid-template-columns: repeat(8, var(--square-size));
        grid-template-rows: repeat(8, var(--square-size));
        margin: 0 auto;
    }
    
    .square {
        width: var(--square-size);
        height: var(--square-size);
        font-size: calc(var(--square-size) * 0.44);
    }

    .square .piece {
        font-size: calc(var(--square-size) * 0.44);
    }

    .square .piece-svg {
        width: calc(var(--square-size) * 0.85);
        height: calc(var(--square-size) * 0.85);
    }
    
    /* Barra de evaluación horizontal bajo la barra de movimientos */
    .board-with-coords .eval-bar-container {
        display: none;
    }

    .eval-bar-mobile {
        display: flex !important;
        align-items: center;
        justify-content: center;
        width: 100%;
        max-width: calc(8 * var(--square-size));
        height: auto;
        padding: 8px 0;
        margin: 0 auto;
    }

    .eval-bar-mobile .eval-bar {
        width: 100%;
        height: 16px;
    }

    .eval-bar-mobile .eval-bar-fill {
        width: 50%;
        height: 100%;
        bottom: auto;
        top: 0;
        left: 0;
        border-radius: 2px 0 0 2px;
    }

    .eval-bar-mobile .eval-bar-label {
        writing-mode: horizontal-tb;
        font-size: 0.6rem;
    }
    
    .rank-labels {
        height: calc(8 * var(--square-size));
    }
    
    .rank-label {
        height: var(--square-size);
        font-size: calc(var(--square-size) * 0.28);
        font-weight: 700;
        min-width: calc(var(--square-size) * 0.44);
        transform: translateY(calc(var(--square-size) * -0.30));
    }
    
    .file-labels {
        width: calc(8 * var(--square-size));
    }
    
    .file-label {
        width: var(--square-size);
        font-size: calc(var(--square-size) * 0.28);
        font-weight: 700;
    }

    .square-coordinate {
        font-size: calc(var(--square-size) * 0.14);
    }

    .board-wrapper {
        display: flex;
        justify-content: center;
        align-items: center;
    }

    /* Ajustar reloj para móviles */
    .chess-clock {
        flex-direction: row;
        gap: 10px;
    }

    .clock-time {
        font-size: 1.28rem;
    }

    .clock-label {
        font-size: 0.95rem;
    }

    .btn {
        padding: 10px 12px;
        font-size: 0.92rem;
    }

    header {
        margin-bottom: 15px;
    }

    .subtitle {
        font-size: 1rem;
    }

    .training-name, .training-moves, .training-desc {
        font-size: 0.88rem;
    }

    .quiz-score {
        font-size: 1rem;
    }

    /* Optimizaciones cross-browser para responsive */
    html {
        -webkit-text-size-adjust: 100%;
        -ms-text-size-adjust: 100%;
    }

    body {
        min-height: 100vh;
        min-height: -webkit-fill-available;
        padding-left: env(safe-area-inset-left);
        padding-right: env(safe-area-inset-right);
    }

    .square {
        -webkit-tap-highlight-color: transparent;
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        user-select: none;
        -webkit-backface-visibility: hidden;
        backface-visibility: hidden;
    }

    .move-history-display {
        -webkit-overflow-scrolling: touch;
    }

    .btn, .nav-btn {
        -webkit-appearance: none;
        -moz-appearance: none;
        appearance: none;
    }

    .rotate-device-overlay {
        padding-left: env(safe-area-inset-left);
        padding-right: env(safe-area-inset-right);
    }
}