/* ---- Fonts ---- */
@font-face {
    font-family: 'Tall';
    src: url('fonts/Tall.otf');
}
@font-face {
    font-family: 'Now';
    src: url('fonts/Now.otf');
}

/* ---- Variables couleurs ---- */
:root {
    --blue: #5d6cb0;
    --blue-dark: #4a5791;
    --gray-light: #f2f2f2;
    --gray-dark: #666;
}

/* ---- Global ---- */
* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: 'Now', sans-serif;
    background-color: #fff;
    color: #000;
    padding-top: 100px; /* espace pour header fixe */
    line-height: 1.6;
}

/* ---- Header ---- */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--blue);
    padding: 1.5rem 2rem;
    box-sizing: border-box;
    border-bottom: 3px solid var(--blue-dark);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

nav ul {
    display: flex;
    justify-content: center;
    align-items: center;
    list-style: none;
    padding: 0;
    margin: 0;
    gap: 2.5rem;
}

nav li { margin: 0; }

nav a {
    color: white;
    text-decoration: none;
    font-weight: bold;
    font-size: 1.4rem;
    padding: 0.75rem 1.25rem;
    border-radius: 5px;
    transition: background-color 0.3s;
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

/* ---- Hero Banner (Accueil) ---- */
.hero {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    min-height: 80vh;
    overflow: hidden;
    background-color: #f5f5f5;
    color: black;
    padding: 2rem;
    box-sizing: border-box;
}

.hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, rgba(245,245,245,0.9) 0%, rgba(245,245,245,0) 40%);
    z-index: 1;
}

.hero-text {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding-right: 2rem;
    z-index: 2;
}

.hero-text h1 {
    font-family: 'Tall';
    font-size: 4rem;
    color: var(--blue);
    margin: 0;
    line-height: 1.3;
    letter-spacing: 2px;
    text-shadow: 1px 1px 6px rgba(0,0,0,0.25);
    text-transform: uppercase;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2;
}

.hero-image img {
    width: 100%;
    max-width: 600px;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

/* ---- Intro ---- */
.intro {
    text-align: center;
    margin: 4rem 2rem;
    font-size: 1.2rem;
    line-height: 1.9;
}

/* Buttons */
.buttons {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.2rem;
    margin-top: 2rem;
}
.btn {
    background-color: var(--blue);
    color: white;
    padding: 1rem 2rem;
    text-decoration: none;
    border-radius: 8px;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: 0 4px 10px rgba(93,108,176,0.3);
    transition: all 0.3s;
}
.btn:hover {
    background-color: var(--blue-dark);
    transform: translateY(-3px);
    box-shadow: 0 6px 14px rgba(93,108,176,0.4);
}

/* ---- Liste Conférences ---- */
.conf-list {
    padding: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

/* Titre principal de la session */
.conf-list h2 {
    font-family: 'Tall', sans-serif;
    font-size: 3.2rem;
    line-height: 1.25;
    text-align: center;
    margin: 0 0 2.2rem 0;
    color: var(--blue);
    letter-spacing: 2px;
    text-transform: uppercase;
    text-shadow: 1px 1px 6px rgba(0,0,0,0.15);
}

/* Conférences */
.conference {
    margin-bottom: 3rem;
    padding: 1.5rem;
    border-left: 4px solid var(--blue);
    background: #fafafa;
    border-radius: 6px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.conference h3 {
    font-family: 'Tall', sans-serif;
    font-size: 2.1rem;
    line-height: 1.3;
    margin: 0 0 0.8rem 0;
    color: var(--blue-dark);
    letter-spacing: 1.2px;
    text-shadow: 0 1px 4px rgba(0,0,0,0.1);
}

.conference p {
    font-size: 1.15rem;
    margin-bottom: 1rem;
    color: #333;
}

/* ---- Partners section ---- */
.partners-section {
    text-align: center;
    margin: 4rem 2rem;
}

.partners-section h2 {
    font-family: 'Tall', sans-serif;
    font-size: 3.5rem;      /* plus grand pour lisibilité */
    color: var(--blue);
    margin-bottom: 1.5rem;
    letter-spacing: 3px;    /* espacement des lettres pour meilleure lisibilité */
    text-transform: uppercase;
    text-shadow: 1px 1px 6px rgba(0,0,0,0.2);
    line-height: 1.05;
}

/* réduire un peu sur mobile */
@media (max-width: 640px) {
  .partners-section h2 { font-size: 2.1rem; letter-spacing: 1.2px; }
}

.partners-section p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
}

.partners-logos {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    align-items: center;
}

.partners-logos img {
    max-height: 60px;
    width: auto;
    object-fit: contain;
}

/* ---- Video wrapper (responsive 16:9) ---- */
.video-wrapper {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 ratio */
    margin-top: 1rem;
    margin-bottom: 1.5rem;
    overflow: hidden;
}

.video-wrapper iframe {
    position: absolute;
    inset: 0;
    width: 100% !important;
    height: 100% !important;
    border: 0;
    border-radius: 8px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
}

/* ---- Fallback / force for any stray iframe (if not wrapped) ----
   We try not to rely solely on !important, but include as safety. */
iframe {
    width: 100% !important;
    height: auto !important;
    aspect-ratio: 16 / 9;
    border-radius: 8px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
    display: block;
    margin-bottom: 2rem;
}

/* ---- Footer ---- */
footer {
    background-color: var(--gray-light);
    text-align: center;
    padding: 1.5rem;
    margin-top: 3rem;
    font-size: 0.9rem;
    color: var(--gray-dark);
    border-top: 1px solid #ddd;
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
    .hero {
        flex-direction: column;
        text-align: center;
    }
    .hero-text {
        padding-right: 0;
        margin-bottom: 1.5rem;
    }
    .hero-text h1 {
        font-size: 2.6rem;
    }
    .conf-list h2 {
        font-size: 2.3rem;
    }
    .conference h3 {
        font-size: 1.7rem;
    }
    .video-wrapper { padding-top: 56.25%; } /* keep 16:9 */
    iframe { aspect-ratio: 16 / 9; }
}