/* Reset CSS et variables */
:root {
    /* Core brand palette: Blue + Blue-Gray + Orange */
    --primary-color: #1a365d;     /* Deep blue (brand primary) */
    --secondary-color: #2b6cb0;   /* Strong blue (actions/links) */
    --accent-color: #ed8936;      /* Warm orange (accents/highlights) */

    /* Supporting colors */
    --causal-purple: #805ad5;     /* Causality theme (keep limited use) */
    --ai-green: #38a169;          /* Supportive success/positive */

    /* Blue-gray neutrals for text and surfaces */
    --text-dark: #1f2937;         /* Slate 800 */
    --text-light: #475569;        /* Slate 600 */
    --text-white: #ffffff;
    --bg-white: #ffffff;
    --bg-light: #f8fafc;          /* Subtle cool light */

    /* Hero/background gradients (more dynamic and modern) */
    --bg-gradient-start: #364254; /* Blue-gray dark with subtle blue */
    --bg-gradient-mid: #4a5568;   /* Blue-gray mid with blue hint */
    --bg-gradient-end: #667084;   /* Blue-gray light with blue warmth */
    
    /* Footer gradient */
    --bg-dark: #2d3748;           /* Sophisticated dark blue-gray */
    
    /* Section alternance */
    --section-alt: #f8fafc;       /* Light blue-gray for alternating sections */

    /* Effects */
    --shadow: 0 4px 12px rgba(26, 54, 93, 0.15);
    --shadow-hover: 0 8px 25px rgba(26, 54, 93, 0.25);
    --transition: all 0.3s ease;
    --border-radius: 12px;
    --max-width: 1200px;
}

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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    scroll-behavior: smooth;
}

/* Layout utilitaires */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--primary-color);
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--secondary-color), var(--accent-color));
    border-radius: 2px;
}

/* Boutons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, var(--secondary-color) 0%, #1d4ed8 100%);
    color: var(--text-white);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
    background: linear-gradient(135deg, #1d4ed8 0%, var(--secondary-color) 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-white);
    border: 2px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.5);
    color: var(--text-white);
    transform: translateY(-2px);
}

/* Navigation */
.navbar {
    background-color: var(--bg-white);
    box-shadow: var(--shadow);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* Language switcher */
.language-switcher {
    position: relative;
}

.lang-btn {
    background: none;
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    padding: 8px 16px;
    border-radius: 25px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-weight: 500;
    font-size: 0.85rem;
    min-width: 80px;
    justify-content: center;
    position: relative;
}

.lang-btn:hover {
    background-color: var(--primary-color);
    color: var(--text-white);
    transform: translateY(-2px);
}

.lang-btn i {
    font-size: 0.9rem;
    opacity: 0.8;
}

#currentLang, .alt-lang {
    font-weight: 600;
    font-size: 0.85rem;
}

.alt-lang {
    opacity: 0.6;
}

.lang-btn:hover .alt-lang {
    opacity: 0.9;
}

.nav-logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--secondary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Menu mobile */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--primary-color);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: 
        radial-gradient(circle at 80% 20%, rgba(139, 163, 194, 0.18), transparent 50%),
        radial-gradient(circle at 20% 80%, rgba(237, 137, 54, 0.22), transparent 58%),
        linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-mid) 50%, var(--bg-gradient-end) 100%);
    color: var(--text-white);
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(1400px 700px at 10% 30%, rgba(255,255,255,0.05), transparent 70%),
        radial-gradient(800px 400px at 90% 70%, rgba(139, 163, 194, 0.1), transparent 60%),
        radial-gradient(700px 350px at 85% 85%, rgba(237, 137, 54, 0.08), transparent 60%),
        url("data:image/svg+xml,%3Csvg width='120' height='120' viewBox='0 0 120 120' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Ccircle cx='60' cy='60' r='3'/%3E%3Ccircle cx='20' cy='20' r='1'/%3E%3Ccircle cx='100' cy='20' r='1'/%3E%3Ccircle cx='20' cy='100' r='1'/%3E%3Ccircle cx='100' cy='100' r='1'/%3E%3Cpath d='M20,60 L100,60 M60,20 L60,100' stroke='%23ffffff' stroke-width='0.5' stroke-opacity='0.03'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    opacity: 0.8;
    z-index: 0;
}

.hero::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(139, 163, 194, 0.06) 0%, transparent 70%);
    transform: rotate(45deg);
    z-index: 0;
}

.hero-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 1;
}

.hero-content {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 5rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: 1.5rem;
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    line-height: 1.7;
    color: rgba(255, 255, 255, 0.9);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin: 1.5rem 0 2.25rem 0;
}

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

.social-link {
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-white);
    text-decoration: none;
    transition: var(--transition);
}

.social-link svg {
    width: 20px;
    height: 20px;
    fill: currentColor;
}

.social-link:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.profile-photo {
    text-align: center;
}

.profile-photo img {
    width: 320px;
    height: 320px;
    border-radius: 24px;
    object-fit: cover;
    border: 4px solid rgba(255, 255, 255, 0.2);
    box-shadow: 
        0 20px 40px rgba(0,0,0,0.25),
        0 8px 16px rgba(0,0,0,0.15),
        inset 0 1px 0 rgba(255,255,255,0.1);
    transition: var(--transition);
    backdrop-filter: blur(2px);
}

.profile-photo img:hover {
    transform: scale(1.05) translateY(-5px);
    box-shadow: 
        0 25px 50px rgba(0,0,0,0.3),
        0 12px 24px rgba(0,0,0,0.2),
        inset 0 1px 0 rgba(255,255,255,0.15);
}

/* About Section */
.about {
    padding: 80px 0;
    background: var(--section-alt);
    position: relative;
}

.about-content {
    display: grid;
    grid-template-columns: 1.7fr 1fr;
    gap: 4rem;
}

/* Center the bio block within its column for improved balance */
.about-text {
    max-width: 65ch;
    margin-left: auto;
    margin-right: auto;
}

/* Slight emphasis for the first paragraph as a lead */
.about-text p:first-of-type {
    font-size: 1.15rem;
}

.about-text p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
    color: var(--text-light);
}

.detail-item {
    margin-bottom: 2rem;
}

.detail-item h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.detail-item ul {
    list-style: none;
    padding-left: 1.5rem;
}

.detail-item li {
    margin-bottom: 0.5rem;
    color: var(--text-light);
    position: relative;
}

.detail-item li::before {
    content: '•';
    color: var(--secondary-color);
    position: absolute;
    left: -1rem;
}

/* Research Section */
.research {
    padding: 80px 0;
    background: var(--bg-light);
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.research-item {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
    text-align: center;
}

.research-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.research-icon {
    width: 80px;
    height: 80px;
    background: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
    color: var(--text-white);
}

.research-item h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.research-item p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.research-link {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.research-link:hover {
    color: var(--primary-color);
}

/* Publications Section */
.publications {
    padding: 80px 0;
    background: var(--bg-white);
    position: relative;
}

.publication-item {
    display: flex;
    gap: 2rem;
    padding: 2rem;
    background: var(--bg-light);
    border-radius: var(--border-radius);
    margin-bottom: 2rem;
    transition: var(--transition);
    border-left: 4px solid var(--secondary-color);
    box-shadow: var(--shadow);
}

.publication-item:hover {
    box-shadow: var(--shadow-hover);
    border-left-color: var(--accent-color);
    transform: translateY(-3px);
}

.pub-year {
    font-size: 1.2rem;
    font-weight: 700;
    min-width: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--causal-purple), var(--secondary-color));
    border-radius: 50%;
    width: 60px;
    height: 60px;
    color: var(--text-white);
    box-shadow: 0 4px 12px rgba(128, 90, 213, 0.3);
}

.pub-content {
    flex: 1;
}

.pub-title {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.pub-authors {
    margin-bottom: 0.5rem;
    color: var(--text-light);
}

.pub-journal {
    margin-bottom: 1rem;
    color: var(--text-light);
    font-style: italic;
}

.pub-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.pub-link {
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.pub-link:hover {
    color: var(--primary-color);
}

.publications-cta {
    text-align: center;
    margin-top: 3rem;
}

/* Teaching Section */
.teaching {
    padding: 80px 0;
    background: var(--bg-white);
    position: relative;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.course-item {
    background: var(--section-alt);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 4px solid var(--ai-green);
    position: relative;
}

/* Différenciation par catégorie */
.course-item[data-category="master"] {
    border-top-color: var(--secondary-color); /* Master - Bleu */
}

.course-item[data-category="bachelor"] {
    border-top-color: var(--ai-green); /* Licence - Vert */
}

.course-item[data-category="summer"] {
    border-top-color: var(--accent-color); /* Licence - Vert */
}

.course-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}

.course-item h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.course-level {
    color: var(--secondary-color);
    font-weight: 500;
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

.course-description {
    color: var(--text-light);
    line-height: 1.6;
    font-size: 0.95rem;
}

.course-institution {
    margin-top: 0.25rem;
    color: var(--text-dark);
    font-weight: 500;
}

/* Meta row and chips for teaching cards */
.course-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.9rem;
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 0.82rem;
    line-height: 1;
    border: 1px solid rgba(0,0,0,0.15);
    background: transparent;
    color: var(--text-dark);
    font-weight: 500;
}

.level-chip {
    background: transparent; /* outline variant */
    border-color: rgba(128, 90, 213, 0.35);
}

.year-chip {
    background: transparent; /* outline variant */
    border-color: rgba(56, 161, 105, 0.35);
}

/* Footer */
.footer {
    background: linear-gradient(135deg, var(--bg-dark) 0%, #1e293b 100%);
    color: var(--text-white);
    padding: 2rem 0;
    text-align: center;
    position: relative;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

/* Conferences Section */
.conferences {
    background: var(--section-alt);
    position: relative;
    padding: 80px 0;
}

.conference-item {
    background: var(--bg-white);
    padding: 2.5rem;
    margin-bottom: 2rem;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--accent-color);
    transition: var(--transition);
    display: flex;
    gap: 2.5rem;
    box-shadow: var(--shadow);
}

.conference-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-hover);
}

.conference-item[data-type="presentation"] {
    border-left-color: var(--secondary-color);
}

.conference-item[data-type="poster"] {
    border-left-color: var(--accent-color);
}

.conference-item[data-type="attendance"] {
    border-left-color: var(--secondary-color);
}

.conf-year {
    font-size: 1.2rem;
    font-weight: 700;
    min-width: 70px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--accent-color);
    color: var(--text-white);
    border-radius: 50%;
    height: 70px;
    width: 70px;
    flex-shrink: 0;
}

.conf-content {
    flex: 1;
}

.conf-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
    gap: 1rem;
}

.conf-title {
    font-size: 1.4rem;
    color: var(--primary-color);
    margin: 0;
    line-height: 1.3;
}

.conf-type {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--causal-purple);
    font-weight: 600;
    background: rgba(138, 43, 226, 0.1);
    padding: 0.4rem 0.8rem;
    border-radius: 15px;
    white-space: nowrap;
}

.conf-details {
    color: var(--text-light);
}

.conf-info {
    margin: 0 0 1rem 0;
    font-size: 1rem;
    line-height: 1.6;
}

.conf-info i {
    color: var(--secondary-color);
    width: 18px;
    margin-right: 0.5rem;
}

.conf-description {
    margin: 1rem 0;
    font-style: italic;
    color: var(--text-light);
    line-height: 1.5;
}

.presentation-details {
    background: rgba(138, 43, 226, 0.08);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    margin: 1rem 0;
    border-left: 3px solid var(--causal-purple);
}

.presentation-details h4 {
    color: var(--causal-purple);
    margin: 0 0 0.5rem 0;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.presentation-details .conf-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    margin-top: 0.5rem;
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.presentation-details .conf-link:hover {
    color: var(--primary-color);
}

.presentation-abstract {
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--text-dark);
    margin: 0;
}

.conf-activities {
    list-style: none;
    padding: 0;
    margin: 1rem 0;
}

.conf-activities li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-light);
}

.conf-activities li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

.conf-website {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
    margin-top: 1rem;
    padding: 0.5rem 1rem;
    background: rgba(59, 130, 246, 0.1);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.conf-website:hover {
    background: var(--secondary-color);
    color: var(--text-white);
    transform: translateY(-2px);
}

/* Responsibilities Section */
.responsibilities {
    background: var(--section-alt);
    position: relative;
    padding: 80px 0;
}

.responsibilities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
    margin-top: 3rem;
}

.responsibility-item {
    background: var(--bg-white);
    padding: 2.5rem 2rem;
    border-radius: var(--border-radius);
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.responsibility-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.resp-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-size: 1.8rem;
    color: var(--text-white);
}

.responsibility-item:nth-child(1) .resp-icon {
    background: linear-gradient(135deg, var(--secondary-color), var(--causal-purple));
}

.responsibility-item:nth-child(2) .resp-icon {
    background: linear-gradient(135deg, var(--ai-green), var(--secondary-color));
}

/* Conference groups */
.conf-group {
  margin-bottom: 2.5rem;
}

.conf-group-title {
  margin: 0 0 1rem 0;
  font-size: 1.4rem;
  color: var(--primary-color);
  border-bottom: 2px solid var(--divider, rgba(0,0,0,0.08));
  padding-bottom: 0.4rem;
}

/* Slight variants by tier (optional) */
.conf-group-major .conf-group-title {
  border-color: var(--secondary-color);
}
.conf-group-workshop .conf-group-title {
  border-color: var(--accent-color);
}
.conf-group-attendance .conf-group-title {
  border-color: var(--muted, rgba(0,0,0,0.15));
}

/* Conference filters */
.conf-filters {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
    margin: 0 0 1rem 0;
    justify-content: center;
}
.conf-filter-btn {
  appearance: none;
  border: 1px solid var(--border, rgba(0,0,0,.12));
  background: var(--bg-white);
  color: var(--text-color);
  padding: .4rem .75rem;
  border-radius: 999px;
  font-size: .95rem;
  cursor: pointer;
  transition: var(--transition);
}
.conf-filter-btn:hover {
  border-color: var(--accent-color);
  transform: translateY(-1px);
}
.conf-filter-btn.active {
  background: var(--accent-color);
  color: var(--text-white);
  border-color: var(--accent-color);
}
@media (max-width: 600px) {
    /* already centered */
}

/* Responsive Design */
@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: var(--transition);
        box-shadow: var(--shadow);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-menu li {
        margin: 1rem 0;
    }

    .nav-right {
        gap: 0.5rem;
    }

    .lang-btn {
        padding: 6px 10px;
        font-size: 0.8rem;
        min-width: 50px;
    }

    .hamburger {
        display: flex;
    }

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

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }
    
    .publication-item {
        flex-direction: column;
        gap: 1rem;
    }
    
    .conference-item {
        flex-direction: column;
        gap: 1rem;
        padding: 1.5rem;
    }
    
    .conf-year {
        align-self: flex-start;
        margin-bottom: 0.5rem;
    }
    
    .conf-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    
    .publications-filter {
        justify-content: center;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
        gap: 1.2rem;
    }
    
    .course-item {
        padding: 1.5rem;
    }
    
    .course-item h4 {
        font-size: 1.2rem;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .courses-grid {
        gap: 1rem;
    }
    
    .course-item {
        padding: 1.2rem;
    }
    
    .course-item h4 {
        font-size: 1.1rem;
    }
    
    .hero-title {
        font-size: 1.8rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .research-grid {
        grid-template-columns: 1fr;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
}

/* Animation pour le scroll */
@media (prefers-reduced-motion: no-preference) {
    .fade-in {
        opacity: 0;
        transform: translateY(20px);
        transition: opacity 0.6s ease, transform 0.6s ease;
    }
    
    .fade-in.visible {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Citation Modals */
.citation-modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: var(--bg-white);
    margin: 5% auto;
    padding: 2rem;
    border-radius: var(--border-radius);
    width: 80%;
    max-width: 700px;
    box-shadow: var(--shadow-hover);
    position: relative;
    max-height: 80vh;
    overflow-y: auto;
}

.close {
    color: var(--text-light);
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
}

.close:hover {
    color: var(--primary-color);
}

.citation-text {
    margin-top: 1rem;
}

.citation-text p {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.citation-text textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--bg-light);
    border-radius: var(--border-radius);
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.4;
    background-color: var(--bg-light);
    color: var(--text-dark);
    resize: vertical;
    min-height: 120px;
    margin-bottom: 1rem;
}

.copy-btn {
    background: linear-gradient(135deg, var(--secondary-color), var(--causal-purple));
    color: var(--text-white);
    border: none;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
    margin-bottom: 1.5rem;
}

.copy-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

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

@media (max-width: 768px) {
    .modal-content {
        width: 95%;
        margin: 10% auto;
        padding: 1.5rem;
    }
    
    .citation-text textarea {
        font-size: 0.8rem;
        min-height: 100px;
    }
}