/* ============================================
   L'ART DES ÉCHECS — CSS Principal
   Design moderne, élégant & responsive
   ============================================ */

:root {
    --primary: #c9a96e;
    --primary-dark: #a07840;
    --primary-light: #e8d4aa;
    --secondary: #1a1a2e;
    --accent: #e94560;
    --dark: #0f0f1a;
    --dark-2: #16213e;
    --dark-3: #1a1a2e;
    --light: #f8f4ef;
    --light-2: #ede8e0;
    --white: #ffffff;
    --text-dark: #1a1a2e;
    --text-muted: #666;
    --text-light: rgba(255,255,255,0.85);
    --board-light: #f0d9b5;
    --board-dark: #b58863;
    --chess-white: #f5f0e0;
    --chess-black: #2c2c2c;
    --shadow: 0 4px 20px rgba(0,0,0,0.12);
    --shadow-lg: 0 10px 50px rgba(0,0,0,0.2);
    --shadow-gold: 0 8px 32px rgba(201,169,110,0.3);
    --radius: 16px;
    --radius-sm: 8px;
    --radius-lg: 24px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-heading: 'Playfair Display', Georgia, serif;
    --font-body: 'Inter', system-ui, sans-serif;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    background: var(--light);
    color: var(--text-dark);
    line-height: 1.7;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul { list-style: none; }

img { max-width: 100%; height: auto; }

/* ============ SCROLLBAR ============ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--dark); }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 3px; }

/* ============ NAVBAR ============ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1rem 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(15, 15, 26, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 0.6rem 0;
    box-shadow: 0 2px 30px rgba(0,0,0,0.3);
}

.nav-container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--white);
}

.logo-icon {
    font-size: 1.8rem;
    filter: drop-shadow(0 0 10px rgba(201,169,110,0.5));
}

.logo-text {
    background: linear-gradient(135deg, var(--white), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.nav-link {
    color: rgba(255,255,255,0.8);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 0.5rem 0.9rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--white);
    background: rgba(201,169,110,0.15);
}

.nav-link.btn-play {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: var(--dark);
    font-weight: 600;
    padding: 0.5rem 1.2rem;
    border-radius: 50px;
}

.nav-link.btn-play:hover {
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    transform: translateY(-1px);
    box-shadow: var(--shadow-gold);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 2px;
    background: var(--white);
    border-radius: 2px;
    transition: var(--transition);
}

/* ============ HERO ============ */
.hero {
    min-height: 100vh;
    background: var(--dark);
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding: 6rem 2rem 4rem;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.chess-pattern {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(135deg, rgba(201,169,110,0.05) 25%, transparent 25%),
        linear-gradient(225deg, rgba(201,169,110,0.05) 25%, transparent 25%),
        linear-gradient(45deg, rgba(201,169,110,0.05) 25%, transparent 25%),
        linear-gradient(315deg, rgba(201,169,110,0.05) 25%, transparent 25%);
    background-size: 80px 80px;
    background-position: 0 0, 0 40px, 40px -40px, -40px 0px;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(201,169,110,0.15) 0%, transparent 70%);
    pointer-events: none;
}

.hero-bg::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(233,69,96,0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    max-width: 1300px;
    margin: 0 auto;
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 4rem;
    position: relative;
    z-index: 1;
}

.hero-content > * { grid-column: 1; }

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(201,169,110,0.15);
    border: 1px solid rgba(201,169,110,0.3);
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0.5rem 1rem;
    border-radius: 50px;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    width: fit-content;
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 900;
    color: var(--white);
    line-height: 1.1;
    animation: fadeInUp 0.6s ease 0.2s both;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 50%, var(--primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: shimmer 3s ease infinite;
}

.hero-subtitle {
    color: var(--text-light);
    font-size: 1.1rem;
    max-width: 520px;
    line-height: 1.8;
    animation: fadeInUp 0.6s ease 0.3s both;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s ease 0.4s both;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.85rem 1.8rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: var(--dark);
    box-shadow: var(--shadow-gold);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(201,169,110,0.5);
}

.btn-secondary {
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
    color: var(--white);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.2);
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 2rem;
    animation: fadeInUp 0.6s ease 0.5s both;
}

.stat {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
}

.stat-label {
    font-size: 0.75rem;
    color: rgba(255,255,255,0.5);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: rgba(255,255,255,0.15);
}

.hero-visual {
    grid-column: 2;
    grid-row: 1 / 6;
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInRight 0.8s ease 0.3s both;
}

.floating-board {
    width: 380px;
    height: 380px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 30px 80px rgba(0,0,0,0.5), 0 0 0 1px rgba(201,169,110,0.2);
    transform-style: preserve-3d;
    animation: float 6s ease-in-out infinite;
}

/* ============ SECTIONS ============ */
.section {
    padding: 6rem 0;
}

.section-dark {
    background: var(--dark-2);
    color: var(--white);
}

.section-chess {
    background: linear-gradient(135deg, var(--dark) 0%, var(--dark-3) 100%);
    color: var(--white);
}

.container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header.light .section-title { color: var(--white); }
.section-header.light .section-subtitle { color: rgba(255,255,255,0.7); }

.section-tag {
    display: inline-block;
    background: rgba(201,169,110,0.15);
    color: var(--primary);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 0.3rem 1rem;
    border-radius: 50px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 1rem;
    border: 1px solid rgba(201,169,110,0.2);
}

.section-title {
    font-family: var(--font-heading);
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1rem;
    line-height: 1.2;
}

.section-subtitle {
    font-size: 1.05rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ============ PIECES GRID ============ */
.pieces-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 2rem;
}

.piece-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.06);
}

.piece-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.piece-header {
    background: linear-gradient(135deg, var(--dark) 0%, var(--dark-3) 100%);
    padding: 2rem;
    display: flex;
    justify-content: center;
    gap: 2rem;
    align-items: center;
}

.piece-symbol {
    font-size: 4rem;
    line-height: 1;
    filter: drop-shadow(0 4px 8px rgba(0,0,0,0.3));
    transition: var(--transition);
}

.piece-symbol.white { color: var(--chess-white); }
.piece-symbol.black { color: var(--chess-black); text-shadow: 0 0 0 2px var(--primary); }

.piece-card:hover .piece-symbol { transform: scale(1.1); }

.piece-body {
    padding: 1.5rem;
}

.piece-name {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.piece-value {
    font-size: 0.85rem;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
}

.piece-desc {
    font-size: 0.92rem;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 1rem;
}

.mini-board {
    width: 100%;
    aspect-ratio: 1;
    max-width: 160px;
    margin: 0 auto 1rem;
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    grid-template-rows: repeat(7, 1fr);
    border-radius: var(--radius-sm);
    overflow: hidden;
    border: 2px solid rgba(0,0,0,0.1);
}

.mini-cell {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
}

.mini-cell.light-sq { background: var(--board-light); }
.mini-cell.dark-sq { background: var(--board-dark); }
.mini-cell.piece-here { 
    background: rgba(201,169,110,0.5);
    font-size: 1rem;
}
.mini-cell.move-here { 
    background: rgba(100,200,100,0.7);
    border-radius: 50%;
}

.piece-move-diagram {
    margin: 1rem 0;
}

.piece-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.tag {
    background: var(--light-2);
    color: var(--text-dark);
    font-size: 0.75rem;
    font-weight: 500;
    padding: 0.25rem 0.7rem;
    border-radius: 50px;
    border: 1px solid rgba(0,0,0,0.08);
}

/* ============ RULES SECTION ============ */
.rules-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
    align-items: start;
}

.rules-tabs {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: sticky;
    top: 100px;
}

.rule-tab {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    padding: 1rem 1.2rem;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-sm);
    color: rgba(255,255,255,0.7);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
    font-family: var(--font-body);
}

.rule-tab:hover {
    background: rgba(201,169,110,0.1);
    color: var(--white);
    border-color: rgba(201,169,110,0.3);
}

.rule-tab.active {
    background: linear-gradient(135deg, rgba(201,169,110,0.25), rgba(201,169,110,0.1));
    color: var(--primary);
    border-color: rgba(201,169,110,0.5);
    font-weight: 600;
}

.rules-content {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.rule-panel {
    display: none;
    padding: 2.5rem;
    animation: fadeIn 0.4s ease;
}

.rule-panel.active { display: block; }

.rule-icon-big {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.rule-panel h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--white);
    margin-bottom: 1rem;
}

.rule-panel p {
    color: rgba(255,255,255,0.7);
    font-size: 1rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.rule-panel p strong { color: var(--primary); }

.rule-highlights {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.highlight-item {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
    padding: 1.2rem;
    background: rgba(255,255,255,0.05);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--primary);
}

.highlight-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.highlight-item strong {
    color: var(--white);
    font-weight: 600;
    display: block;
    margin-bottom: 0.3rem;
}

.highlight-item p {
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
    line-height: 1.6;
    margin: 0;
}

/* ============ OPENINGS ============ */
.openings-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.opening-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.06);
    position: relative;
}

.opening-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.opening-card.featured {
    grid-column: span 1;
    border: 2px solid var(--primary);
}

.opening-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--primary);
    color: var(--dark);
    font-size: 0.7rem;
    font-weight: 700;
    padding: 0.25rem 0.7rem;
    border-radius: 50px;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    z-index: 1;
}

.opening-visual {
    background: linear-gradient(135deg, var(--dark-2), var(--dark-3));
    padding: 1.5rem;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 120px;
}

.mini-chess-board {
    width: 100px;
    height: 100px;
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    grid-template-rows: repeat(8, 1fr);
    border-radius: 4px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.4);
}

.mini-chess-cell {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.55rem;
    line-height: 1;
}

.mini-chess-cell.l { background: var(--board-light); }
.mini-chess-cell.d { background: var(--board-dark); }
.mini-chess-cell.moved {
    background: rgba(100, 200, 100, 0.6) !important;
}

.opening-info {
    padding: 1.5rem;
}

.opening-info h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 0.7rem;
    color: var(--text-dark);
}

.opening-moves {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.8rem;
    flex-wrap: wrap;
}

.move {
    background: var(--dark);
    color: var(--primary);
    font-family: monospace;
    font-size: 0.8rem;
    font-weight: 600;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
}

.move-arrow { color: var(--text-muted); font-size: 1rem; }

.opening-info p {
    font-size: 0.88rem;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 1rem;
}

.opening-stats {
    display: flex;
    gap: 0.8rem;
    flex-wrap: wrap;
}

.opening-stats span {
    font-size: 0.78rem;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-weight: 500;
}

.opening-principle {
    background: linear-gradient(135deg, var(--dark), var(--dark-3));
    color: var(--white);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    border: 1px solid rgba(201,169,110,0.2);
}

.opening-principle h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.7rem;
    color: var(--primary);
}

.principles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.principle {
    text-align: center;
}

.principle-num {
    font-size: 3rem;
    font-family: var(--font-heading);
    font-weight: 900;
    color: rgba(201,169,110,0.2);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.principle h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 0.7rem;
}

.principle p {
    font-size: 0.88rem;
    color: rgba(255,255,255,0.6);
    line-height: 1.7;
}

/* ============ TIPS SECTION ============ */
.tips-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-bottom: 4rem;
}

.tips-category {}

.category-title {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    color: var(--primary);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.7rem;
}

.tips-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.tip-item {
    display: flex;
    gap: 1.2rem;
    align-items: flex-start;
    padding: 1.2rem;
    background: rgba(255,255,255,0.05);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255,255,255,0.08);
    transition: var(--transition);
}

.tip-item:hover {
    background: rgba(201,169,110,0.08);
    border-color: rgba(201,169,110,0.2);
}

.tip-number {
    width: 36px;
    height: 36px;
    background: var(--primary);
    color: var(--dark);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.tip-content h4 {
    color: var(--white);
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 0.3rem;
}

.tip-content p {
    color: rgba(255,255,255,0.6);
    font-size: 0.88rem;
    line-height: 1.6;
}

.tactical-motifs {}

.tactical-motifs h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.7rem;
}

.motifs-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.motif-card {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius);
    padding: 1.5rem;
    text-align: center;
    transition: var(--transition);
}

.motif-card:hover {
    background: rgba(201,169,110,0.1);
    border-color: rgba(201,169,110,0.3);
    transform: translateY(-4px);
}

.motif-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: block;
}

.motif-card h4 {
    color: var(--white);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.motif-card p {
    color: rgba(255,255,255,0.55);
    font-size: 0.85rem;
    line-height: 1.6;
}

/* ============ CHAMPIONS ============ */
.champions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.champion-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.06);
    position: relative;
    overflow: hidden;
}

.champion-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
}

.champion-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.champion-rank {
    position: absolute;
    top: 1.2rem;
    right: 1.2rem;
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 900;
    color: rgba(201,169,110,0.3);
}

.champion-avatar {
    margin-bottom: 1rem;
}

.avatar-placeholder {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--dark), var(--dark-3));
    color: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    border: 3px solid var(--primary-light);
}

.champion-info h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.3rem;
}

.champion-era {
    font-size: 0.8rem;
    color: var(--primary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    display: block;
    margin-bottom: 0.8rem;
}

.champion-rating {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--light-2);
    border-radius: var(--radius-sm);
    padding: 0.6rem 1rem;
    margin-bottom: 1rem;
}

.elo-label {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.elo-value {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary);
}

.champion-info p {
    font-size: 0.88rem;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 1rem;
}

.champion-facts {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.fact {
    background: var(--light-2);
    font-size: 0.75rem;
    color: var(--text-dark);
    padding: 0.25rem 0.7rem;
    border-radius: 50px;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    border: 1px solid rgba(0,0,0,0.06);
}

.fact i { color: var(--primary); }

/* ============ CHESS APP / ÉCHIQUIER ============ */
.chess-app {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
    align-items: start;
}

.chess-controls {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.control-group {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius);
    padding: 1.2rem;
}

.control-group h4 {
    font-size: 0.8rem;
    color: var(--primary);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 0.8rem;
}

.control-btn {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    width: 100%;
    padding: 0.7rem 1rem;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-sm);
    color: rgba(255,255,255,0.8);
    font-size: 0.85rem;
    font-family: var(--font-body);
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 0.5rem;
    text-align: left;
}

.control-btn:last-child { margin-bottom: 0; }

.control-btn:hover,
.control-btn.active {
    background: rgba(201,169,110,0.15);
    border-color: rgba(201,169,110,0.3);
    color: var(--primary);
}

.move-history {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius);
    padding: 1.2rem;
}

.move-history h4 {
    font-size: 0.8rem;
    color: var(--primary);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 0.8rem;
}

.history-list {
    min-height: 80px;
    max-height: 150px;
    overflow-y: auto;
    font-family: monospace;
    font-size: 0.85rem;
    color: rgba(255,255,255,0.7);
}

.history-empty {
    color: rgba(255,255,255,0.3);
    font-size: 0.8rem;
    font-style: italic;
    font-family: var(--font-body);
}

.move-entry {
    display: flex;
    gap: 0.5rem;
    padding: 0.2rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.05);
}

.move-num { color: var(--primary); font-weight: 600; }
.move-white { color: var(--white); }
.move-black { color: rgba(255,255,255,0.6); }

.board-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.chess-board-container {
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5), 0 0 0 2px rgba(201,169,110,0.3);
    position: relative;
}

.chessboard {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    grid-template-rows: repeat(8, 1fr);
    width: 100%;
    max-width: 560px;
    aspect-ratio: 1;
    user-select: none;
}

.chess-cell {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.2rem;
    cursor: pointer;
    transition: background 0.1s ease;
    position: relative;
}

.chess-cell.light { background: var(--board-light); }
.chess-cell.dark { background: var(--board-dark); }

.chess-cell.selected {
    background: rgba(100, 200, 100, 0.6) !important;
    box-shadow: inset 0 0 0 3px rgba(80,180,80,0.8);
}

.chess-cell.possible-move {
    background: rgba(100, 200, 100, 0.35) !important;
}

.chess-cell.possible-move::after {
    content: '';
    position: absolute;
    width: 35%;
    height: 35%;
    background: rgba(80,180,80,0.6);
    border-radius: 50%;
}

.chess-cell.possible-capture {
    box-shadow: inset 0 0 0 4px rgba(200,80,80,0.7) !important;
}

.chess-cell.coord-file::after {
    content: attr(data-file);
    position: absolute;
    bottom: 2px;
    right: 4px;
    font-size: 0.65rem;
    font-weight: 600;
    opacity: 0.7;
    pointer-events: none;
    line-height: 1;
}

.chess-cell.coord-rank::before {
    content: attr(data-rank);
    position: absolute;
    top: 2px;
    left: 4px;
    font-size: 0.65rem;
    font-weight: 600;
    opacity: 0.7;
    pointer-events: none;
    line-height: 1;
}

.chess-cell.light.coord-file::after { color: var(--board-dark); }
.chess-cell.dark.coord-file::after { color: var(--board-light); }
.chess-cell.light.coord-rank::before { color: var(--board-dark); }
.chess-cell.dark.coord-rank::before { color: var(--board-light); }

.chess-piece {
    font-size: 2rem;
    line-height: 1;
    pointer-events: none;
    transition: transform 0.1s ease;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.4));
}

.chess-cell:hover .chess-piece { transform: scale(1.1); }

.board-info {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 50px;
    padding: 0.6rem 1.5rem;
}

.turn-indicator {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    color: var(--white);
    font-size: 0.9rem;
    font-weight: 500;
}

.turn-dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 2px solid rgba(255,255,255,0.3);
    transition: var(--transition);
}

.turn-dot.white-turn { background: var(--white); }
.turn-dot.black-turn { background: var(--chess-black); }

.captured-row {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    flex-wrap: wrap;
}

.captured-label {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.5);
}

.captured-piece {
    font-size: 1rem;
    opacity: 0.7;
}

/* ============ FOOTER ============ */
.footer {
    background: var(--dark);
    color: var(--white);
    padding: 4rem 0 0;
    border-top: 1px solid rgba(201,169,110,0.15);
}

.footer-content {
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 2rem 3rem;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 3rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.7rem;
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 1rem;
}

.footer-logo .logo-icon { font-size: 1.6rem; }

.footer-brand p {
    color: rgba(255,255,255,0.5);
    font-size: 0.9rem;
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.footer-social {
    display: flex;
    gap: 0.8rem;
}

.footer-social a {
    width: 38px;
    height: 38px;
    background: rgba(255,255,255,0.07);
    border: 1px solid rgba(255,255,255,0.12);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
    color: var(--dark);
    border-color: var(--primary);
    transform: translateY(-3px);
}

.footer-links h4 {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--white);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 1.2rem;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.footer-links a {
    color: rgba(255,255,255,0.5);
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--primary);
    transform: translateX(4px);
    display: inline-block;
}

.footer-info h4 {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--white);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 1.2rem;
}

.fun-fact {
    background: rgba(201,169,110,0.1);
    border: 1px solid rgba(201,169,110,0.2);
    border-radius: var(--radius-sm);
    padding: 1rem;
    display: flex;
    gap: 0.8rem;
    align-items: flex-start;
}

.fun-fact i {
    color: var(--primary);
    font-size: 1rem;
    margin-top: 2px;
    flex-shrink: 0;
}

.fun-fact span {
    color: rgba(255,255,255,0.6);
    font-size: 0.85rem;
    line-height: 1.6;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.07);
    padding: 1.5rem 2rem;
    text-align: center;
    color: rgba(255,255,255,0.3);
    font-size: 0.85rem;
    max-width: 1300px;
    margin: 0 auto;
}

/* ============ SCROLL TO TOP ============ */
.scroll-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: var(--dark);
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.1rem;
    box-shadow: var(--shadow-gold);
    transition: var(--transition);
    opacity: 0;
    pointer-events: none;
    z-index: 999;
}

.scroll-top.visible {
    opacity: 1;
    pointer-events: all;
}

.scroll-top:hover {
    background: var(--primary-light);
    transform: translateY(-4px);
}

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

@keyframes fadeInRight {
    from { opacity: 0; transform: translateX(50px); }
    to { opacity: 1; transform: translateX(0); }
}

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

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    33% { transform: translateY(-12px) rotate(1deg); }
    66% { transform: translateY(-6px) rotate(-1deg); }
}

@keyframes shimmer {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============ RESPONSIVE ============ */
@media (max-width: 1200px) {
    .champions-grid { grid-template-columns: repeat(2, 1fr); }
    .openings-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero-content > * { grid-column: 1; }
    .hero-visual { display: none; }
    .hero-buttons { justify-content: center; }
    .hero-stats { justify-content: center; }
    .hero-badge { margin: 0 auto; }
    .hero-subtitle { margin: 0 auto; }

    .rules-layout { grid-template-columns: 1fr; }
    .rules-tabs {
        flex-direction: row;
        flex-wrap: wrap;
        position: static;
    }
    .rule-tab { flex: 1; min-width: 120px; text-align: center; justify-content: center; }

    .chess-app { grid-template-columns: 1fr; }
    .chess-controls {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }
    .board-wrapper { width: 100%; }
    .chessboard { max-width: 480px; }

    .footer-content { grid-template-columns: 1fr 1fr; gap: 2rem; }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 280px;
        background: rgba(10,10,20,0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 0.5rem;
        transition: right 0.3s ease;
        padding: 2rem;
        border-left: 1px solid rgba(201,169,110,0.2);
        z-index: 999;
    }

    .nav-menu.open { right: 0; }
    .nav-toggle { display: flex; z-index: 1001; }
    .nav-link { font-size: 1rem; padding: 0.8rem 1.5rem; width: 100%; text-align: center; }

    .pieces-grid { grid-template-columns: 1fr; }
    .openings-grid { grid-template-columns: 1fr; }
    .champions-grid { grid-template-columns: 1fr; }
    .motifs-grid { grid-template-columns: repeat(2, 1fr); }
    .principles-grid { grid-template-columns: 1fr; }
    .tips-container { grid-template-columns: 1fr; }

    .chess-controls { grid-template-columns: 1fr; }
    .chessboard { max-width: 380px; }
    .chess-piece { font-size: 1.5rem; }

    .footer-content { grid-template-columns: 1fr; }
    .footer-bottom { padding: 1rem 2rem; }

    .hero-stats { flex-direction: column; align-items: center; gap: 1rem; }
    .stat-divider { width: 60px; height: 1px; }
}

@media (max-width: 480px) {
    .section { padding: 4rem 0; }
    .hero { padding: 5rem 1rem 3rem; }
    .container { padding: 0 1rem; }
    .chessboard { max-width: 320px; }
    .chess-piece { font-size: 1.3rem; }
    .motifs-grid { grid-template-columns: 1fr; }
    .hero-title { font-size: 2rem; }
    .section-title { font-size: 1.6rem; }
}