:root {
    --primary-color: #6a0dad; /* Violet vibrant */
    --secondary-color: #8A2BE2; /* Bleu-violet */
    --accent-color: #ffd700; /* Or */
    --neutral-light: #f8f9fa;
    --neutral-dark: #343a40;
    --text-color: #333;
    --font-header: 'Montserrat', sans-serif;
    --font-body: 'Poppins', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--text-color);
    line-height: 1.6;
    background-color: #fff;
}

.container {
    max-width: 1100px;
    margin: auto;
    padding: 0 2rem;
}

h1, h2, h3 {
    font-family: var(--font-header);
    color: var(--primary-color);
    margin-bottom: 1rem;
}

h1 {
    font-size: 4.5rem;
    color: #fff;
    -webkit-text-stroke: 2px var(--primary-color);
    text-shadow: 0 0 3px var(--primary-color);
}

h2 {
    font-size: 2.5rem;
    text-align: center;
    padding-bottom: 1rem;
    border-bottom: 3px solid var(--accent-color);
    display: inline-block;
    margin-bottom: 2rem;
}

section {
    padding: 5rem 0;
}

section:nth-child(odd) {
    background-color: var(--neutral-light);
}

/* Header & Floating Navbar */
#header {
    background-color: rgba(255, 255, 255, 0.9);
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    backdrop-filter: blur(5px);
}

#navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

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

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li a {
    padding: 0.5rem 1rem;
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 600;
    transition: color 0.3s ease, background-color 0.3s ease;
    border-radius: 5px;
}

.nav-links li a:hover {
    color: #fff;
    background-color: var(--secondary-color);
}

/* Accueil Section */
#accueil {
    background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.4)), url('depositphotos_196695510-stock-photo-strasbourgfamous-city-europe.jpg') no-repeat center center/cover;
    min-height: 90vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
}

#accueil .sous-titre {
    font-size: 4.5rem;
    margin-bottom: 2rem;
    -webkit-text-stroke: 2px var(--primary-color);
    text-shadow: 0 0 3px var(--primary-color);
}

#accueil .dates {
    font-size: 4.5rem;
    -webkit-text-stroke: 2px var(--primary-color);
    text-shadow: 0 0 3px var(--primary-color);
}

.btn-principal {
    background-color: var(--accent-color);
    color: var(--neutral-dark);
    padding: 0.8rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.btn-principal:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.btn-secondaire {
    background-color: transparent;
    color: var(--primary-color);
    padding: 0.6rem 1.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    border: 2px solid var(--primary-color);
    transition: background-color 0.3s ease, color 0.3s ease;
}

.btn-secondaire:hover {
    background-color: var(--primary-color);
    color: #fff;
}

/* Centered Titles */
#dates .container, #programme .container, #intervenants .container, #sponsors .container, #inscription .container, #contact .container, #faq .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

/* Dates Section */
.dates-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    width: 100%;
    margin-top: 2rem;
}

.date-item {
    background: #fff;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    border-left: 5px solid var(--secondary-color);
}

.date-item h3 {
    color: var(--secondary-color);
}

/* Informations Section */
.info-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    text-align: left;
    align-items: start;
    width: 100%;
    margin-top: 2rem;
}

.info-grid h3 {
    color: var(--secondary-color);
}

.info-grid p {
    margin-bottom: 1rem;
}

/* Intervenants Section */
.intervenants-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    width: 100%;
    margin-top: 2rem;
}

.intervenant-carte {
    background: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.intervenant-carte:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.intervenant-carte img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.intervenant-carte h3 {
    margin-top: 1rem;
    font-size: 1.2rem;
}

.intervenant-carte p {
    font-size: 0.9rem;
    color: #666;
    padding: 0 1rem 1rem;
}

/* FAQ Section */
.faq-item {
    background: #fff;
    padding: 1.5rem;
    border-radius: 5px;
    margin-bottom: 1rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    text-align: left;
    width: 100%;
    max-width: 800px;
}

/* Program Table */
.program-table {
    width: 100%;
    margin-top: 2rem;
    border-collapse: collapse;
    background-color: #fff;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    border-radius: 10px;
    overflow: hidden;
}

.program-table thead {
    background-color: var(--primary-color);
    color: #fff;
}

.program-table th {
    padding: 1.5rem 1rem;
    font-family: var(--font-header);
    font-size: 1.2rem;
    font-weight: 600;
    text-align: center;
    border-right: 2px solid rgba(255, 255, 255, 0.2);
}

.program-table th:last-child {
    border-right: none;
}

.program-table td {
    padding: 1.2rem 1rem;
    text-align: center;
    vertical-align: top;
    border-bottom: 1px solid #e0e0e0;
    border-right: 1px solid #e0e0e0;
}

.program-table td:last-child {
    border-right: none;
}

.program-table tbody tr:last-child td {
    border-bottom: none;
}

.program-table tbody tr:hover {
    background-color: var(--neutral-light);
}

.program-table td strong {
    color: var(--secondary-color);
    font-weight: 600;
}

.program-table td:empty {
    background-color: #f9f9f9;
}

/* Pratique Links */
.pratique-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
    width: 100%;
}

.pratique-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    text-decoration: none;
    color: var(--primary-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.pratique-link:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.pratique-link i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

.pratique-link span {
    font-size: 1.1rem;
    font-weight: 600;
    text-align: center;
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.3s ease;
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: #fff;
    margin: auto;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.3);
    width: 90%;
    max-width: 700px;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    animation: slideIn 0.3s ease;
}

.modal-content h3 {
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    font-size: 1.8rem;
}

.modal-content p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.modal-content ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.modal-content ul li {
    margin-bottom: 0.5rem;
}

.modal-content a {
    color: var(--secondary-color);
    text-decoration: underline;
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 2rem;
    font-weight: bold;
    color: var(--neutral-dark);
    cursor: pointer;
    transition: color 0.3s ease;
}

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

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

@keyframes slideIn {
    from {
        transform: translateY(-50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}


/* Footer */
footer {
    background-color: var(--neutral-dark);
    color: #fff;
    text-align: center;
    padding: 2rem 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
        -webkit-text-stroke: 1px var(--primary-color);
    }

    #accueil .sous-titre,
    #accueil .dates {
        font-size: 2.5rem;
        -webkit-text-stroke: 1px var(--primary-color);
    }

    h2 {
        font-size: 2rem;
    }

    #navbar {
        flex-direction: column;
    }

    .nav-links {
        margin-top: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    .nav-links li a {
        padding: 0.5rem 0.7rem;
    }

    .dates-grid,
    .info-grid {
        grid-template-columns: 1fr;
    }

    #accueil {
        min-height: 70vh;
    }

    /* Make program table scrollable on mobile */
    .program-table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
    }

    .program-table th,
    .program-table td {
        padding: 0.8rem 0.5rem;
        font-size: 0.9rem;
    }
}