/* ===== EXPERTISES.CSS - Version optimisée ===== */
/* Pasa Analytics - Styles optimisés pour le référencement et l'accessibilité */

/* ===== VARIABLES CSS ===== */
:root {
    /* Mode Jour (Par défaut) */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --bg-overlay: rgba(255, 255, 255, 0.95);
    
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-tertiary: #64748b;
    --text-on-accent: #ffffff;
    
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    --border-dark: #cbd5e1;
    
    --shadow-color: rgba(0, 0, 0, 0.08);
    --shadow-color-light: rgba(0, 0, 0, 0.04);
    --shadow-color-dark: rgba(0, 0, 0, 0.12);
    
    --accent-primary: #3b82f6;
    --accent-primary-hover: #2563eb;
    --accent-secondary: #8b5cf6;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-error: #ef4444;
    --accent-gradient: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --accent-gradient-hover: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
    
    --radius-xs: 4px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 24px;
    --radius-full: 9999px;
    
    --shadow-xs: 0 1px 2px 0 var(--shadow-color-light);
    --shadow-sm: 0 1px 3px 0 var(--shadow-color);
    --shadow-md: 0 4px 6px -1px var(--shadow-color);
    --shadow-lg: 0 10px 15px -3px var(--shadow-color);
    --shadow-xl: 0 20px 25px -5px var(--shadow-color);
    --shadow-2xl: 0 25px 50px -12px var(--shadow-color-dark);
    --shadow-inner: inset 0 2px 4px 0 var(--shadow-color-light);
    
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: 400ms cubic-bezier(0.68, -0.55, 0.265, 1.55);
    
    --z-index-dropdown: 1000;
    --z-index-sticky: 1020;
    --z-index-fixed: 1030;
    --z-index-modal: 1040;
    --z-index-popover: 1050;
    --z-index-tooltip: 1060;
}

[data-theme="dark"] {
    /* Mode Nuit */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --bg-card: #1e293b;
    --bg-overlay: rgba(15, 23, 42, 0.95);
    
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-tertiary: #94a3b8;
    --text-on-accent: #ffffff;
    
    --border-color: #475569;
    --border-light: #334155;
    --border-dark: #64748b;
    
    --shadow-color: rgba(0, 0, 0, 0.25);
    --shadow-color-light: rgba(0, 0, 0, 0.15);
    --shadow-color-dark: rgba(0, 0, 0, 0.35);
    
    --accent-primary: #60a5fa;
    --accent-primary-hover: #3b82f6;
    --accent-secondary: #a78bfa;
    --accent-success: #34d399;
    --accent-warning: #fbbf24;
    --accent-error: #f87171;
    --accent-gradient: linear-gradient(135deg, #60a5fa 0%, #a78bfa 100%);
    --accent-gradient-hover: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    -moz-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 1rem;
    font-weight: 400;
    transition: background-color var(--transition-base), color var(--transition-base);
    overflow-x: hidden;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

::selection {
    background-color: var(--accent-primary);
    color: var(--text-on-accent);
}

::-moz-selection {
    background-color: var(--accent-primary);
    color: var(--text-on-accent);
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text-primary);
    letter-spacing: -0.025em;
}

h1 {
    font-size: 3rem;
    font-weight: 800;
}

h2 {
    font-size: 2.25rem;
}

h3 {
    font-size: 1.75rem;
    color: var(--accent-primary);
}

h4 {
    font-size: 1.25rem;
    color: var(--text-secondary);
    font-weight: 600;
}

h5 {
    font-size: 1.125rem;
    font-weight: 600;
}

h6 {
    font-size: 1rem;
    font-weight: 600;
}

p {
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
    cursor: pointer;
}

a:hover, a:focus {
    color: var(--accent-primary-hover);
    text-decoration: underline;
}

a:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

strong, b {
    font-weight: 600;
}

em, i {
    font-style: italic;
}

small {
    font-size: 0.875rem;
}

blockquote {
    border-left: 4px solid var(--accent-primary);
    padding-left: 1.5rem;
    margin: 2rem 0;
    color: var(--text-secondary);
    font-style: italic;
}

code {
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
    background-color: var(--bg-tertiary);
    padding: 0.2em 0.4em;
    border-radius: var(--radius-sm);
    font-size: 0.875em;
    color: var(--accent-primary);
}

pre {
    background-color: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin: 2rem 0;
    border: 1px solid var(--border-color);
}

pre code {
    background: none;
    padding: 0;
    color: inherit;
}

/* ===== LISTS - CORRIGÉ ===== */
ul, ol {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
    color: var(--text-secondary);
}

ul {
    list-style-type: none;
}

ol {
    list-style-type: decimal;
}

/* Correction spécifique pour les listes dans .desc */
.desc ul {
    list-style: none;
    margin: 1.5rem 0;
    padding-left: 0;
}

.desc li {
    position: relative;
    margin-bottom: 0.75rem;
    padding-left: 1.75rem;
    line-height: 1.6;
    color: var(--text-secondary);
}

.desc li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent-primary);
    font-weight: bold;
    top: 0;
    width: 1.5rem;
    text-align: center;
}

/* ===== EXPERTISE GRID LISTS - CORRECTION COMPLÈTE ===== */
.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin: 2.5rem 0;
}

.expertise-category {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    border: 1px solid var(--border-color);
    transition: all var(--transition-base);
    height: 100%;
}

.expertise-category:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-primary);
}

.expertise-category h4 {
    margin-bottom: 1.25rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border-color);
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
}

.expertise-category ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.expertise-category li {
    position: relative;
    padding: 0.75rem 0 0.75rem 2rem;
    margin: 0;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-light);
    line-height: 1.5;
    font-size: 0.95rem;
    min-height: 2.5rem;
    display: flex;
    align-items: center;
}

.expertise-category li:last-child {
    border-bottom: none;
}

.expertise-category li::before {
    content: "✓";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    color: var(--accent-primary);
    font-weight: 900;
    font-size: 1rem;
    width: 1.5rem;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ===== LAYOUT & CONTAINERS ===== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

@media (max-width: 640px) {
    .container {
        padding: 0 1rem;
    }
}

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    line-height: 1.5;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    white-space: nowrap;
    user-select: none;
    position: relative;
    overflow: hidden;
}

.btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 5px;
    height: 5px;
    background: rgba(255, 255, 255, 0.5);
    opacity: 0;
    border-radius: 100%;
    transform: scale(1, 1) translate(-50%);
    transform-origin: 50% 50%;
}

.btn:focus:not(:active)::after {
    animation: ripple 1s ease-out;
}

@keyframes ripple {
    0% {
        transform: scale(0, 0);
        opacity: 0.5;
    }
    100% {
        transform: scale(20, 20);
        opacity: 0;
    }
}

.btn-primary {
    background: var(--accent-gradient);
    color: var(--text-on-accent);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover, .btn-primary:focus {
    background: var(--accent-gradient-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    text-decoration: none;
}

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

.btn-outline {
    background: transparent;
    color: var(--accent-primary);
    border-color: var(--accent-primary);
}

.btn-outline:hover, .btn-outline:focus {
    background: var(--accent-primary);
    color: var(--text-on-accent);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
    border-radius: var(--radius-lg);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-block {
    width: 100%;
    display: flex;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

/* ===== NAVBAR ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--bg-overlay);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    z-index: var(--z-index-fixed);
    box-shadow: var(--shadow-sm);
    border-bottom: 1px solid var(--border-color);
    transition: all var(--transition-base);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-brand .logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    transition: transform var(--transition-base);
}

.nav-brand .logo:hover {
    transform: translateY(-1px);
}

.logo-icon {
    width: 44px;
    height: 44px;
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-on-accent);
    font-size: 1.25rem;
    flex-shrink: 0;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
}

.logo-subtitle {
    font-size: 0.75rem;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    line-height: 1.2;
}

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

.nav-list {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    list-style: none;
}

.nav-item {
    position: relative;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    text-decoration: none;
    white-space: nowrap;
}

.nav-link:hover, .nav-link:focus, .nav-link.active {
    background: var(--bg-secondary);
    color: var(--text-primary);
    text-decoration: none;
}

.nav-link i:last-child {
    font-size: 0.75rem;
    transition: transform var(--transition-fast);
}

.dropdown:hover .nav-link i:last-child {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2xl);
    padding: 1.5rem;
    min-width: 400px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--transition-base);
    z-index: var(--z-index-dropdown);
    border: 1px solid var(--border-color);
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.dropdown-section h4 {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 1rem;
    color: var(--text-tertiary);
    font-weight: 600;
}

.dropdown-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    text-decoration: none;
}

.dropdown-link:hover, .dropdown-link:focus {
    background: var(--bg-secondary);
    color: var(--text-primary);
    text-decoration: none;
    transform: translateX(4px);
}

.dropdown-link i {
    width: 20px;
    color: var(--accent-primary);
    font-size: 1rem;
}

.nav-tools {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-left: 1rem;
}

.theme-toggle {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: 0.875rem;
    font-weight: 500;
}

.theme-toggle:hover, .theme-toggle:focus {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-color: var(--accent-primary);
    outline: none;
}

.language-switch select {
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='currentColor' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 16px;
    padding-right: 2.5rem;
}

.language-switch select:hover, .language-switch select:focus {
    border-color: var(--accent-primary);
    outline: none;
    background-color: var(--bg-tertiary);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
}

.nav-toggle .bar {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition-base);
}

.nav-toggle.active .bar:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.nav-toggle.active .bar:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active .bar:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* ===== HERO SECTION ===== */
.hero {
    padding: 100px 0 80px;
    background: var(--bg-secondary);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 70%;
    height: 100%;
    background: var(--accent-gradient);
    opacity: 0.05;
    clip-path: polygon(100% 0, 100% 100%, 0 100%);
    pointer-events: none;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

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

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.25rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 8s ease infinite;
    background-size: 200% 200%;
}

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

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.hero-graphic {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    33% { transform: translateY(-20px) rotate(2deg); }
    66% { transform: translateY(10px) rotate(-2deg); }
}

.graphic-circle {
    width: 300px;
    height: 300px;
    background: var(--accent-gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-on-accent);
    font-size: 5rem;
    box-shadow: var(--shadow-2xl);
    position: relative;
    overflow: hidden;
}

.graphic-circle::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(
        to right,
        transparent,
        rgba(255, 255, 255, 0.9),
        transparent
    );
    transform: rotate(30deg);
    animation: shine 3s ease-in-out infinite;
}

@keyframes shine {
    0% { transform: translateX(-100%) rotate(30deg); }
    100% { transform: translateX(100%) rotate(30deg); }
}

/* ===== MAIN CONTENT ===== */
.main {
    padding: 80px 0;
    min-height: 60vh;
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 3rem;
    align-items: start;
}

.content-main {
    min-height: 500px;
}

.content-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: 3rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: box-shadow var(--transition-base);
}

.content-card:hover {
    box-shadow: var(--shadow-lg);
}

.desc {
    margin-bottom: 3rem;
}

.desc:last-child {
    margin-bottom: 0;
}

.desc h3 {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border-color);
}

.desc h3 a {
    color: inherit;
    text-decoration: none;
}

.desc h3 a:hover {
    color: var(--accent-primary);
    text-decoration: underline;
}

.desc h4 {
    margin: 1.5rem 0 0.75rem;
    color: var(--text-primary);
}

.desc p {
    line-height: 1.7;
    margin-bottom: 1.25rem;
}

.article-meta {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-tertiary);
    font-size: 0.875rem;
}

.reading-time {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.reading-time i {
    color: var(--accent-primary);
}

/* ===== SIDEBAR ===== */
.sidebar {
    position: sticky;
    top: 100px;
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
}

.sidebar.hidden {
    display: none;
}

.sidebar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    background: var(--bg-card);
    z-index: 1;
}

.sidebar-title {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.sidebar-title h3 {
    margin: 0;
    font-size: 1.125rem;
    color: var(--text-primary);
}

.sidebar-close {
    display: none;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    width: 32px;
    height: 32px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    align-items: center;
    justify-content: center;
}

.sidebar-close:hover, .sidebar-close:focus {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-color: var(--accent-primary);
    outline: none;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.sidebar-nav a {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    text-decoration: none;
    font-weight: 500;
}

.sidebar-nav a:hover, .sidebar-nav a:focus, .sidebar-nav a.active {
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding-left: 1.25rem;
    text-decoration: none;
}

.sidebar-nav a i {
    width: 20px;
    color: var(--accent-primary);
    font-size: 0.875rem;
}

.sidebar-footer {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.sidebar-stats {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--text-tertiary);
    font-size: 0.875rem;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 0.375rem;
}

.stat-item i {
    color: var(--accent-primary);
}

/* ===== FIGURES & MEDIA ===== */
figure {
    margin: 2rem 0;
    text-align: center;
}

figure img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    display: block;
    margin: 0 auto;
}

figure img:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-lg);
}

figure figcaption {
    margin-top: 0.75rem;
    color: var(--text-tertiary);
    font-size: 0.875rem;
    font-style: italic;
    line-height: 1.4;
}

.twosome {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
    margin: 2rem 0;
}

.foursome {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
    margin: 2rem 0;
}

.foursome > div {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

video {
    width: 100%;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    margin: 1.5rem 0;
    display: block;
    background: var(--bg-tertiary);
}

/* ===== FORMS ===== */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
    font-size: 0.95rem;
}

.input-with-icon,
.textarea-with-icon {
    position: relative;
}

.input-with-icon i,
.textarea-with-icon i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-tertiary);
    z-index: 1;
}

.textarea-with-icon i {
    top: 1.25rem;
    transform: none;
}

.input-with-icon input,
.textarea-with-icon textarea {
    width: 100%;
    padding: 0.75rem 1rem 0.75rem 3rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    transition: all var(--transition-fast);
    font-family: inherit;
}

.textarea-with-icon textarea {
    padding-left: 3rem;
    min-height: 120px;
    resize: vertical;
}

.input-with-icon input:focus,
.textarea-with-icon textarea:focus,
select:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

select {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    transition: all var(--transition-fast);
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='currentColor' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 16px;
    padding-right: 2.5rem;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.4;
}

.checkbox-label input {
    margin-top: 0.25rem;
    accent-color: var(--accent-primary);
    flex-shrink: 0;
}

/* ===== FOOTER ===== */
.footer {
    background: var(--bg-secondary);
    padding: 4rem 0 2rem;
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2.5rem;
    margin-bottom: 3rem;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.footer-description {
    font-size: 0.875rem;
    color: var(--text-tertiary);
    line-height: 1.6;
}

.footer-title {
    font-size: 1.125rem;
    margin-bottom: 1.25rem;
    color: var(--text-primary);
    font-weight: 600;
}

.footer-links {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    font-size: 0.95rem;
}

.footer-links a:hover, .footer-links a:focus {
    color: var(--accent-primary);
    text-decoration: underline;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.contact-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color var(--transition-fast);
}

.contact-link:hover, .contact-link:focus {
    color: var(--accent-primary);
    text-decoration: underline;
}

.contact-link i {
    color: var(--accent-primary);
    width: 20px;
    text-align: center;
}

.social-links {
    display: flex;
    gap: 0.75rem;
    margin-top: 1rem;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    color: var(--text-secondary);
    transition: all var(--transition-base);
    text-decoration: none;
}

.social-link:hover, .social-link:focus {
    background: var(--accent-primary);
    color: var(--text-on-accent);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-tertiary);
    font-size: 0.875rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-meta {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.views-count {
    display: flex;
    align-items: center;
    gap: 0.375rem;
}

.views-count i {
    color: var(--accent-primary);
}

.sitemap-link {
    color: var(--text-tertiary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.sitemap-link:hover, .sitemap-link:focus {
    color: var(--accent-primary);
    text-decoration: underline;
}

/* ===== UTILITY CLASSES ===== */
.text-gradient {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    transition: all var(--transition-base);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.icon-box {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    color: var(--text-on-accent);
    font-size: 1.5rem;
}

/* ===== ANIMATIONS ===== */
.animate {
    animation: fadeInUp 0.6s ease-out forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: var(--radius-full);
    border: 2px solid var(--bg-secondary);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary-hover);
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 3rem;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .content-wrapper {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
    }
    
    h2 {
        font-size: 2rem;
    }
    
    h3 {
        font-size: 1.5rem;
    }
    
    .hero {
        padding: 120px 0 60px;
    }
    
    .hero-title {
        font-size: 2.75rem;
    }
    
    .hero-subtitle {
        font-size: 1.125rem;
    }
    
    .graphic-circle {
        width: 240px;
        height: 240px;
        font-size: 4rem;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--bg-card);
        padding: 1.5rem;
        box-shadow: var(--shadow-xl);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
        z-index: var(--z-index-modal);
        max-height: calc(100vh - 72px);
        overflow-y: auto;
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-list {
        flex-direction: column;
        align-items: stretch;
        gap: 0.5rem;
    }
    
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        border: none;
        padding: 1rem 0 0 1.5rem;
        min-width: auto;
        background: transparent;
    }
    
    .dropdown-grid {
        grid-template-columns: 1fr;
    }
    
    .nav-tools {
        margin-left: 0;
        margin-top: 1.5rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .sidebar {
        position: fixed;
        top: 0;
        right: -300px;
        bottom: 0;
        width: 300px;
        z-index: var(--z-index-modal);
        transition: right var(--transition-base);
        border-radius: 0;
        border-left: 1px solid var(--border-color);
        max-height: 100vh;
    }
    
    .sidebar:not(.hidden) {
        right: 0;
    }
    
    .sidebar-close {
        display: flex;
    }
    
    .twosome,
    .foursome {
        grid-template-columns: 1fr;
    }
    
    .content-card {
        padding: 2rem;
    }
}

@media (max-width: 640px) {
    .hero-title {
        font-size: 2.25rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: stretch;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }
    
    .footer-meta {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .graphic-circle {
        width: 200px;
        height: 200px;
        font-size: 3.5rem;
    }
    
    .expertise-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.75rem;
    }
    
    h3 {
        font-size: 1.375rem;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .nav-container {
        padding: 0 1rem;
    }
    
    .sidebar {
        width: 100%;
        right: -100%;
    }
    
    .content-card {
        padding: 1.5rem;
    }
}

/* ===== PRINT STYLES ===== */
@media print {
    .navbar,
    .sidebar,
    .footer,
    .theme-toggle,
    .hero-actions,
    .nav-toggle,
    .breadcrumb {
        display: none !important;
    }
    
    .hero {
        padding: 40px 0;
    }
    
    body {
        background: white !important;
        color: black !important;
        font-size: 12pt;
        line-height: 1.5;
    }
    
    a {
        color: blue !important;
        text-decoration: underline !important;
    }
    
    .content-card {
        box-shadow: none !important;
        border: none !important;
        padding: 0 !important;
    }
    
    .hero .container {
        display: block !important;
    }
    
    .hero-graphic {
        display: none !important;
    }
    
    h1, h2, h3, h4, h5, h6 {
        page-break-after: avoid;
    }
    
    p, ul, ol {
        page-break-inside: avoid;
    }
}

/* ===== ACCESSIBILITY ===== */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--accent-primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    z-index: var(--z-index-popover);
    text-decoration: none;
    transition: top var(--transition-fast);
}

.skip-to-content:focus {
    top: 0;
    outline: none;
}

/* ===== LOADING STATES ===== */
.loading {
    position: relative;
    overflow: hidden;
}

.loading::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.2),
        transparent
    );
    animation: loading 1.5s infinite;
}

@keyframes loading {
    0% { left: -100%; }
    100% { left: 100%; }
}

/* ===== FOCUS VISIBLE POLYFILL ===== */
.js-focus-visible :focus:not(.focus-visible) {
    outline: none;
}

/* ===== MATHJAX STYLES ===== */
.MathJax {
    color: var(--text-primary) !important;
    font-size: 1.1em !important;
}

.mjx-chtml {
    overflow-x: auto;
    overflow-y: hidden;
}