/* ============= CSS VARIABLES ============= */
:root {
    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 12px;
    --space-lg: 16px;
    --space-xl: 20px;
    --space-2xl: 24px;
    --space-3xl: 32px;
    --space-4xl: 40px;
    
    /* Colors */
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --primary-light: rgba(59, 130, 246, 0.1);
    --text-primary: #1e293b;
    /* ACCESSIBILITÉ: Contraste amélioré (4.5:1 minimum sur blanc) */
    --text-secondary: #475569;
    --text-muted: #475569;
    
    /* Couleurs "texte" plus sombres (AA sur fonds clairs) */
    --primary-text: #1e3a8a;
    --color-success-text: #065f46;
    --color-warning-text: #92400e;
    --color-error-text: #991b1b;
    --color-easy-text: #065f46;
    --color-medium-text: #1e3a8a;
    --color-hard-text: #92400e;
    --color-expert-text: #991b1b;
    --color-master-text: #5b21b6;
    
    /* Difficulty Colors */
    --color-easy: #10b981;
    --color-easy-light: rgba(16, 185, 129, 0.1);
    --color-medium: #3b82f6;
    --color-medium-light: rgba(59, 130, 246, 0.1);
    --color-hard: #f59e0b;
    --color-hard-light: rgba(245, 158, 11, 0.1);
    --color-expert: #ef4444;
    --color-expert-light: rgba(239, 68, 68, 0.1);
    --color-master: #8b5cf6;
    --color-master-light: rgba(139, 92, 246, 0.1);
    
    /* Semantic Colors */
    --color-success: #059669;
    --color-success-light: rgba(5, 150, 105, 0.1);
    --color-warning: #d97706;
    --color-warning-light: rgba(217, 119, 6, 0.1);
    --color-error: #dc2626;
    --color-error-light: rgba(220, 38, 38, 0.1);
    --color-gold: #eab308;
    --color-gold-light: rgba(234, 179, 8, 0.15);
    
    /* Borders & Shadows */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 8px 25px rgba(0, 0, 0, 0.15);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-bounce: 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    
    /* Layout */
    --header-height: 70px;
}

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

/* ACCESSIBILITÉ: Permettre la sélection de texte (suppression de user-select: none global) */
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    color: var(--text-primary);
    line-height: 1.5;
    min-height: 100vh;
    /* ACCESSIBILITÉ: Texte sélectionnable par défaut */
}

/* Éléments interactifs non-sélectionnables */
button,
.btn,
.rule-card,
.mode-card,
.nav-btn {
    -webkit-user-select: none;
    -moz-user-select: none;
    user-select: none;
}

/* ============= PAGE VIEWPORT ============= */
#page-viewport {
    min-height: 100vh;
}

/* ============= LAYOUT ============= */
.scoring-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: var(--space-md) var(--space-md) var(--space-xl);
    min-height: calc(100vh - var(--header-height));
}

/* ============= PAGE HEADER ============= */
.page-header {
    text-align: center;
    margin-bottom: var(--space-xl);
}

.page-main-title {
    font-size: 32px;
    font-weight: 800;
    color: var(--text-primary); /* fallback accessible */
    margin-bottom: var(--space-md);
}

/* Gradient seulement si supporté */
@supports (-webkit-background-clip: text) {
    .page-main-title {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
    }
}

@media (forced-colors: active) {
    .page-main-title {
        -webkit-text-fill-color: CanvasText;
        background: none;
    }
}

.page-subtitle {
    font-size: 16px;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ============= BUTTONS ============= */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    border: none;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5);
}

.btn-secondary {
    background: white;
    color: var(--text-secondary);
    border: 1px solid #e2e8f0;
}

.btn-secondary:hover {
    background: #f8fafc;
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-1px);
}

/* ACCESSIBILITÉ: Focus visible amélioré */
.btn:focus-visible,
button:focus-visible,
a:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 3px;
}

/* ============= GLASS CARDS ============= */
.glass-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-3xl);
    margin-bottom: var(--space-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid rgba(226, 232, 240, 0.8);
    position: relative;
    overflow: hidden;
    /* PERFORMANCE: content-visibility pour les sections hors viewport */
    content-visibility: auto;
    contain-intrinsic-size: auto 500px;
}

/* ============= SECTION HEADERS ============= */
.section-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.section-description {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: var(--space-3xl);
    font-weight: 500;
    line-height: 1.6;
}

/* ============= ICONS ============= */
.icon-svg {
    width: 56px;
    height: 56px;
    transition: transform var(--transition-bounce);
    flex-shrink: 0;
}

/* PERFORMANCE: Remplacer les sélecteurs [src*="..."] par des classes */
.icon-grille {
    width: 100px;
    height: 100px;
}

.icon-trophy {
    width: 72px;
    height: 72px;
    filter: drop-shadow(0 4px 12px rgba(234, 179, 8, 0.4));
}

/* Hover uniquement sur les icônes (pas les cartes entières) */
.icon-svg:hover {
    transform: scale(1.15) rotate(-5deg);
}

/* ============= FORMULA BOX ============= */
.formula-box {
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    color: var(--text-primary);
    border: 2px solid var(--primary);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    margin: var(--space-xl) 0;
    text-align: center;
    font-size: 16px;
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.15);
}

.formula-box-inline {
    font-size: 15px;
    margin: 12px 0;
}

.formula-box-large {
    font-size: 18px;
    margin: 24px 0;
}

.formula-highlight {
    font-weight: 700;
    color: var(--primary);
    background: rgba(59, 130, 246, 0.1);
    padding: 2px 8px;
    border-radius: 4px;
}

.formula-note {
    font-size: 14px;
    opacity: 0.8;
    margin-top: 8px;
    display: block;
}

/* ============= RULES GRID ============= */
.rules-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
    margin: var(--space-3xl) 0;
}

.rules-grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.rules-grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

.rule-card {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: var(--radius-md);
    padding: var(--space-xl);
    text-align: center;
    min-height: 140px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.rule-icon {
    font-size: 24px;
    margin-bottom: var(--space-md);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 70px;
}

.rule-icon .icon-svg {
    width: 56px;
    height: 56px;
}

.rule-icon .icon-grille {
    width: 100px;
    height: 100px;
}

.rule-icon .icon-trophy {
    width: 64px;
    height: 64px;
}

.rule-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.rule-title.large {
    font-size: 16px;
    font-weight: 700;
}

.rule-value {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: var(--space-xs);
    padding: 4px 12px;
    border-radius: 20px;
    display: inline-block;
}

.rule-value.positive { 
    color: var(--color-success-text);
    background: var(--color-success-light);
}

.rule-value.negative { 
    color: var(--color-error-text);
    background: var(--color-error-light);
}

.rule-value.neutral { 
    color: var(--primary-text);
    background: var(--primary-light);
}

.rule-value.warning {
    color: var(--color-warning-text);
    background: var(--color-warning-light);
}

.rule-description {
    font-size: 12px;
    color: var(--text-muted);
    line-height: 1.4;
    font-weight: 500;
}

/* ============= EXAMPLE BOX ============= */
.example-box {
    background: linear-gradient(135deg, #f0f9ff, #e0f2fe);
    border: 2px solid var(--primary);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    margin: var(--space-xl) 0;
}

.example-content-wrapper {
    display: flex;
    align-items: flex-start;
    gap: var(--space-xl);
}

.example-icon {
    flex-shrink: 0;
    width: 88px;
    height: 88px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 24px rgba(59, 130, 246, 0.2);
    border: 2px solid rgba(59, 130, 246, 0.1);
}

.example-icon .icon-svg {
    width: 52px;
    height: 52px;
}

.example-icon .icon-grille {
    width: 64px;
    height: 64px;
}

.example-details {
    flex: 1;
}

.example-title {
    font-size: 17px;
    font-weight: 700;
    color: #0369a1;
    margin-bottom: var(--space-md);
}

.example-content {
    color: #0c4a6e;
    font-size: 14px;
    font-weight: 500;
    line-height: 1.6;
}

.example-content strong {
    color: #0369a1;
    font-weight: 700;
}

/* ============= CALCULATION STEPS ============= */
.calculation-steps {
    background: white;
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    margin: var(--space-md) 0;
    font-family: 'SF Mono', 'Fira Code', 'Inter', system-ui, sans-serif;
    font-size: 13px;
    border: 1px solid rgba(59, 130, 246, 0.2);
    color: #334155;
    font-weight: 500;
    line-height: 1.8;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.05);
}

.calculation-steps strong {
    color: var(--primary);
}

.final-score {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-md);
    font-weight: 700;
    text-align: center;
    margin-top: var(--space-md);
    font-size: 15px;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

/* ============= DIFFICULTY GRID ============= */
.difficulty-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: var(--space-lg);
    margin: var(--space-xl) 0;
}

.difficulty-card {
    border-radius: var(--radius-md);
    padding: var(--space-xl) var(--space-lg);
    text-align: center;
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
}

.difficulty-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
}

.difficulty-card.easy,
.difficulty-card:nth-child(1) {
    background: var(--color-easy-light);
    border: 2px solid var(--color-easy);
}
.difficulty-card.easy::before,
.difficulty-card:nth-child(1)::before { background: var(--color-easy); }
.difficulty-card.easy .difficulty-bonus,
.difficulty-card:nth-child(1) .difficulty-bonus { color: var(--color-easy-text); }

.difficulty-card.medium,
.difficulty-card:nth-child(2) {
    background: var(--color-medium-light);
    border: 2px solid var(--color-medium);
}
.difficulty-card.medium::before,
.difficulty-card:nth-child(2)::before { background: var(--color-medium); }
.difficulty-card.medium .difficulty-bonus,
.difficulty-card:nth-child(2) .difficulty-bonus { color: var(--color-medium-text); }

.difficulty-card.hard,
.difficulty-card:nth-child(3) {
    background: var(--color-hard-light);
    border: 2px solid var(--color-hard);
}
.difficulty-card.hard::before,
.difficulty-card:nth-child(3)::before { background: var(--color-hard); }
.difficulty-card.hard .difficulty-bonus,
.difficulty-card:nth-child(3) .difficulty-bonus { color: var(--color-hard-text); }

.difficulty-card.expert,
.difficulty-card:nth-child(4) {
    background: var(--color-expert-light);
    border: 2px solid var(--color-expert);
}
.difficulty-card.expert::before,
.difficulty-card:nth-child(4)::before { background: var(--color-expert); }
.difficulty-card.expert .difficulty-bonus,
.difficulty-card:nth-child(4) .difficulty-bonus { color: var(--color-expert-text); }

.difficulty-card.master,
.difficulty-card:nth-child(5) {
    background: var(--color-master-light);
    border: 2px solid var(--color-master);
}
.difficulty-card.master::before,
.difficulty-card:nth-child(5)::before { background: var(--color-master); }
.difficulty-card.master .difficulty-bonus,
.difficulty-card:nth-child(5) .difficulty-bonus { color: var(--color-master-text); }

.difficulty-name {
    font-size: 11px;
    font-weight: 700;
    color: var(--text-secondary);
    margin-bottom: var(--space-sm);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.difficulty-bonus {
    font-size: 22px;
    font-weight: 800;
}

/* ============= STEPS LIST ============= */
.steps-list {
    list-style: none;
    padding: 0;
}

.step-item {
    display: flex;
    align-items: flex-start;
    gap: var(--space-lg);
    margin-bottom: var(--space-xl);
    padding: var(--space-xl);
    background: white;
    border-radius: var(--radius-lg);
    border: 1px solid #e2e8f0;
}

.step-number {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 14px;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.step-content {
    flex: 1;
}

.step-title {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
    font-size: 15px;
}

.step-description {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
    font-weight: 500;
}

/* ============= MODES GRID ============= */
.modes-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    margin: var(--space-xl) 0;
}

.mode-card {
    padding: var(--space-2xl);
    border-radius: var(--radius-lg);
    border: 2px solid;
    min-height: 120px;
}

.mode-card.practice {
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    border-color: #e2e8f0;
}

.mode-card.ranked {
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    border-color: var(--primary);
}

.mode-title {
    font-weight: 700;
    font-size: 18px;
    margin-bottom: var(--space-md);
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.mode-title .icon-svg {
    width: 48px;
    height: 48px;
}

.mode-title .icon-grille {
    width: 80px;
    height: 80px;
}

.mode-title .icon-trophy {
    width: 64px;
    height: 64px;
}

.mode-card.practice .mode-title {
    color: var(--text-primary);
}

.mode-card.ranked .mode-title {
    color: #1d4ed8;
}

.mode-description {
    font-size: 14px;
    margin-bottom: var(--space-lg);
    font-weight: 500;
    line-height: 1.5;
}

.mode-card.practice .mode-description {
    color: var(--text-muted);
}

.mode-card.ranked .mode-description {
    color: #0369a1;
}

.mode-features {
    list-style: none;
    padding: 0;
}

.mode-features li {
    padding: var(--space-sm) 0;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 500;
}

.mode-features li::before {
    content: '\2713';
    color: var(--color-success-text);
    font-weight: 700;
    font-size: 14px;
    width: 20px;
    height: 20px;
    background: var(--color-success-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.mode-card.practice .mode-features li {
    color: var(--text-secondary);
}

.mode-card.ranked .mode-features li {
    color: #0c4a6e;
}

/* ============= ERROR STATE ============= */
.error-state {
    text-align: center;
    padding: 60px 20px;
    background: white;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.error-title {
    font-size: 20px;
    font-weight: 600;
    margin: 16px 0 8px 0;
    color: var(--text-primary);
}

.error-text {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

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

/* ============= RESPONSIVE ============= */
@media (max-width: 768px) {
    /* Header mobile */
    #header-container {
        display: none !important;
    }
    
    #page-viewport {
        padding-top: 0;
    }
    
    .mobile-back-button {
        display: flex !important;
    }
    
    /* Container */
    .scoring-container {
        padding: 12px;
        padding-top: 60px;
        min-height: 100vh;
    }

    /* Page header */
    .page-main-title {
        font-size: 24px;
    }
    
    .page-subtitle {
        font-size: 14px;
    }

    /* Glass cards */
    .glass-card {
        padding: var(--space-2xl);
        margin-bottom: var(--space-lg);
        border-radius: var(--radius-lg);
        /* Désactiver content-visibility sur mobile pour éviter les problèmes de scroll */
        content-visibility: visible;
        contain-intrinsic-size: auto;
    }

    /* Section headers */
    .section-title {
        font-size: 20px;
        gap: var(--space-md);
        flex-wrap: wrap;
    }
    
    .section-title .icon-svg {
        width: 48px;
        height: 48px;
    }
    
    .section-title .icon-grille {
        width: 80px;
        height: 80px;
    }

    .section-description {
        font-size: 14px;
        margin-bottom: var(--space-2xl);
    }

    /* Rules grid */
    .rules-grid,
    .rules-grid-2,
    .rules-grid-3 {
        grid-template-columns: 1fr;
        gap: var(--space-md);
        margin: var(--space-2xl) 0;
    }

    /* Rule cards */
    .rule-card {
        min-height: 90px;
        padding: var(--space-lg);
    }

    .rule-icon {
        min-height: 56px;
    }
    
    .rule-icon .icon-svg {
        width: 48px;
        height: 48px;
    }
    
    .rule-icon .icon-grille {
        width: 80px;
        height: 80px;
    }

    .rule-title {
        font-size: 14px;
    }

    .rule-value {
        font-size: 16px;
    }

    .rule-description {
        font-size: 12px;
    }

    /* Formula box */
    .formula-box {
        padding: var(--space-lg);
        font-size: 14px;
        text-align: left;
    }

    /* Example boxes */
    .example-box {
        padding: var(--space-lg);
    }

    .example-content-wrapper {
        flex-direction: column;
        gap: var(--space-md);
        text-align: center;
    }

    .example-icon {
        align-self: center;
        width: 72px;
        height: 72px;
    }
    
    .example-icon .icon-svg {
        width: 44px;
        height: 44px;
    }
    
    .example-icon .icon-grille {
        width: 64px;
        height: 64px;
    }

    .example-title {
        font-size: 15px;
        text-align: center;
    }

    .example-content {
        font-size: 14px;
        text-align: left;
    }

    /* Calculation steps */
    .calculation-steps {
        padding: var(--space-md);
        font-size: 13px;
    }

    .final-score {
        font-size: 13px;
        padding: var(--space-sm) var(--space-md);
    }

    /* Difficulty grid */
    .difficulty-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-md);
    }

    .difficulty-card {
        min-height: 90px;
        padding: var(--space-md);
    }

    /* Modes grid */
    .modes-grid {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }

    .mode-card {
        padding: var(--space-lg);
        min-height: auto;
    }

    .mode-title {
        font-size: 15px;
        justify-content: center;
    }

    .mode-description {
        text-align: center;
        font-size: 14px;
    }

    /* Buttons tactiles */
    .btn {
        min-height: 44px;
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    .scoring-container {
        padding: 8px;
        padding-top: 56px;
    }

    .glass-card {
        padding: var(--space-lg);
    }

    .page-main-title {
        font-size: 20px;
    }

    .section-title {
        font-size: 18px;
    }

    .difficulty-grid {
        grid-template-columns: 1fr;
    }

    .btn {
        min-height: 48px;
        font-size: 16px;
    }
}

/* ============= REDUCED MOTION ============= */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .icon-svg:hover {
        transform: none;
    }
    
    .btn:hover {
        transform: none;
    }
}

/* ============= HIGH CONTRAST ============= */
@media (prefers-contrast: high) {
    .glass-card,
    .rule-card,
    .example-box,
    .step-item,
    .mode-card,
    .difficulty-card {
        border-width: 3px;
        border-color: currentColor;
    }
    
    .btn:focus-visible,
    a:focus-visible {
        outline-width: 4px;
    }
}

/* ============= PRINT ============= */
@media print {
    .mobile-back-button,
    #header-container,
    .btn {
        display: none !important;
    }
    
    .glass-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
    }
    
    .scoring-container {
        max-width: 100%;
        padding: 0;
    }
}