:root {
    --primary-blue: #0056a6;
    --primary-dark: #00386c;
    --accent-silver: #a6a6a6;
    --light-bg: #f8fafc;
    --white: #ffffff;
    --text-dark: #2c3e50;
    --text-muted: #64748b;
    --transition-smooth: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
    font-family: 'Poppins', sans-serif;
    color: var(--text-dark);
    background-color: var(--light-bg);
    line-height: 1.6;
    overflow-x: hidden;
}

/* --- Header y Navegación --- */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    transition: var(--transition-smooth);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

.logo-nav {
    display: flex;
    align-items: center;
    text-decoration: none;
}

    .logo-nav img {
        height: 48px;
        width: auto;
        object-fit: contain;
        transition: var(--transition-smooth);
    }

    .logo-nav:hover img {
        transform: scale(1.03);
    }

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
    align-items: center;
}

    .nav-links a {
        text-decoration: none;
        color: var(--text-dark);
        font-weight: 600;
        position: relative;
        padding: 0.5rem 0;
        transition: var(--transition-smooth);
    }

        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0%;
            height: 3px;
            background: var(--primary-blue);
            border-radius: 2px;
            transition: var(--transition-smooth);
        }

        .nav-links a:hover::after {
            width: 100%;
        }

.btn-register-nav {
    background: var(--primary-blue);
    color: var(--white) !important;
    padding: 0.6rem 1.4rem !important;
    border-radius: 30px;
    box-shadow: 0 4px 15px rgba(0, 86, 166, 0.3);
    transition: var(--transition-smooth) !important;
}

    .btn-register-nav::after {
        display: none !important;
    }

    .btn-register-nav:hover {
        transform: translateY(-2px);
        background: var(--primary-dark);
        box-shadow: 0 6px 20px rgba(0, 86, 166, 0.4);
    }

/* --- Hero Section / Banner Principal --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, rgba(0, 56, 108, 0.85), rgba(0, 86, 166, 0.7)), url('https://images.unsplash.com/photo-1629909613654-28e377c37b09?auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
    color: var(--white);
    padding: 8rem 2rem 4rem;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    animation: fadeInUp 1s ease;
}

.hero-content p {
    font-size: 1.15rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    animation: fadeInUp 1s ease 0.2s backwards;
}

.hero-badges {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease 0.4s backwards;
}

.badge {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(5px);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 8px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero-card-logo {
    background: var(--white);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
    text-align: center;
    animation: float 4s ease-in-out infinite;
}

    .hero-card-logo img {
        max-width: 100%;
        height: auto;
        border-radius: 10px;
    }

/* --- Ponentes (Carrusel con Afiches Completos) --- */
.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

    .section-title h2 {
        font-size: 2.5rem;
        color: var(--primary-dark);
        position: relative;
        display: inline-block;
    }

        .section-title h2::after {
            content: '';
            display: block;
            width: 60px;
            height: 4px;
            background: var(--primary-blue);
            margin: 10px auto 0;
            border-radius: 2px;
        }

.speakers-section {
    padding: 6rem 2rem;
    background: var(--white);
}

.carousel-container {
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    overflow: hidden;
    padding: 1rem 0.5rem;
}

.carousel-track {
    display: flex;
    gap: 2rem;
    transition: transform 0.5s cubic-bezier(0.25, 1, 0.5, 1);
}

.speaker-card {
    min-width: calc(33.333% - 1.35rem);
    background: #ffffff;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(0, 0, 0, 0.08);
    transition: var(--transition-smooth);
    display: flex;
    flex-direction: column;
    cursor: pointer;
}

    .speaker-card:hover {
        transform: translateY(-8px);
        box-shadow: 0 20px 40px rgba(0, 86, 166, 0.18);
    }

.speaker-poster-wrapper {
    position: relative;
    width: 100%;
    height: 480px;
    background: #f1f5f9;
    overflow: hidden;
}

.speaker-poster-img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    background-color: #f8fafc;
    transition: var(--transition-smooth);
}

.speaker-card:hover .speaker-poster-img {
    transform: scale(1.03);
}

.speaker-overlay-btn {
    position: absolute;
    inset: 0;
    background: rgba(0, 56, 108, 0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition-smooth);
}

.speaker-card:hover .speaker-overlay-btn {
    opacity: 1;
}

.view-btn {
    background: var(--white);
    color: var(--primary-blue);
    padding: 0.8rem 1.4rem;
    border-radius: 30px;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
    display: flex;
    align-items: center;
    gap: 8px;
}

.speaker-info {
    padding: 1.2rem;
    text-align: center;
    background: var(--white);
    border-top: 1px solid #edf2f7;
}

    .speaker-info h3 {
        color: var(--primary-dark);
        font-size: 1.2rem;
        margin-bottom: 0.2rem;
    }

    .speaker-info p {
        color: var(--primary-blue);
        font-weight: 600;
        font-size: 0.88rem;
    }

.carousel-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
}

.carousel-btn {
    background: var(--white);
    border: 2px solid var(--primary-blue);
    color: var(--primary-blue);
    width: 45px;
    height: 45px;
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: flex;
    align-items: center;
    justify-content: center;
}

    .carousel-btn:hover {
        background: var(--primary-blue);
        color: var(--white);
    }

/* --- Modal Lightbox --- */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(5px);
    justify-content: center;
    align-items: center;
    padding: 2rem;
    animation: fadeIn 0.3s ease;
}

    .modal.show {
        display: flex;
    }

.modal-content-wrapper {
    position: relative;
    max-width: 90vw;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.modal-img {
    max-width: 100%;
    max-height: 85vh;
    object-fit: contain;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.close-modal {
    position: absolute;
    top: -40px;
    right: 0;
    color: var(--white);
    font-size: 2rem;
    cursor: pointer;
    transition: var(--transition-smooth);
}

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

/* --- Programa Académico --- */
.program-section {
    padding: 6rem 2rem;
    background: var(--light-bg);
}

.program-tabs {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.tab-btn {
    padding: 0.8rem 2rem;
    border: none;
    background: var(--white);
    color: var(--text-dark);
    font-weight: 600;
    font-size: 1rem;
    border-radius: 30px;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    transition: var(--transition-smooth);
}

    .tab-btn.active, .tab-btn:hover {
        background: var(--primary-blue);
        color: var(--white);
        transform: translateY(-2px);
    }

.program-content {
    max-width: 900px;
    margin: 0 auto;
}

.day-schedule {
    display: none;
    flex-direction: column;
    gap: 1.5rem;
    animation: fadeIn 0.5s ease;
}

    .day-schedule.active {
        display: flex;
    }

.schedule-item {
    background: var(--white);
    border-left: 5px solid var(--primary-blue);
    border-radius: 12px;
    padding: 1.5rem 2rem;
    display: grid;
    grid-template-columns: 120px 1fr;
    align-items: center;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.03);
    transition: var(--transition-smooth);
}

    .schedule-item:hover {
        transform: translateX(10px);
        box-shadow: 0 8px 25px rgba(0, 86, 166, 0.1);
    }

.schedule-time {
    font-weight: 700;
    color: var(--primary-blue);
    font-size: 1.1rem;
}

.schedule-detail h4 {
    font-size: 1.1rem;
    color: var(--primary-dark);
    margin-bottom: 0.3rem;
}

.schedule-detail p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* --- Instituciones Participantes (Carrusel Automático) --- */
.institutions-section {
    padding: 6rem 2rem;
    background: var(--white);
    overflow: hidden;
}

.inst-carousel-container {
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    overflow: hidden;
    padding: 1rem 0;
}

.inst-track {
    display: flex;
    gap: 2rem;
    transition: transform 0.6s ease-in-out;
}

.inst-card {
    min-width: calc(25% - 1.5rem);
    background: var(--light-bg);
    padding: 2rem 1.5rem;
    border-radius: 16px;
    text-align: center;
    border: 1px solid #e2e8f0;
    transition: var(--transition-smooth);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 180px;
}

.inst-logo-img {
    max-width: 100%;
    max-height: 80px;
    object-fit: contain;
    margin-bottom: 0.8rem;
    filter: grayscale(30%);
    transition: var(--transition-smooth);
}

.inst-card h4 {
    color: var(--primary-dark);
    font-size: 0.95rem;
    font-weight: 600;
}

.inst-card:hover {
    transform: translateY(-8px);
    background: var(--white);
    border-color: var(--primary-blue);
    box-shadow: 0 15px 30px rgba(0, 86, 166, 0.12);
}

    .inst-card:hover .inst-logo-img {
        filter: grayscale(0%);
        transform: scale(1.08);
    }

/* --- Footer Call To Action --- */
footer {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-blue));
    color: var(--white);
    padding: 5rem 2rem 2rem;
    text-align: center;
}

.footer-cta {
    max-width: 800px;
    margin: 0 auto 4rem;
}

    .footer-cta h2 {
        font-size: 2.5rem;
        margin-bottom: 1rem;
    }

.btn-cta {
    display: inline-block;
    background: var(--white);
    color: var(--primary-blue);
    padding: 1rem 2.5rem;
    border-radius: 40px;
    font-weight: 700;
    text-decoration: none;
    font-size: 1.1rem;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
    transition: var(--transition-smooth);
    margin-top: 1.5rem;
}

    .btn-cta:hover {
        transform: translateY(-3px) scale(1.05);
        box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
        background: var(--light-bg);
    }

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 2rem;
    font-size: 0.9rem;
    opacity: 0.8;
}

/* --- Keyframes --- */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-12px);
    }
}

/* Responsivo */
@media (max-width: 992px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-badges {
        justify-content: center;
    }

    .speaker-card {
        min-width: calc(50% - 1rem);
    }

    .inst-card {
        min-width: calc(33.333% - 1.35rem);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .speaker-card {
        min-width: 100%;
    }

    .inst-card {
        min-width: calc(50% - 1rem);
    }

    .schedule-item {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }

    .speaker-poster-wrapper {
        height: 400px;
    }
}

@media (max-width: 480px) {
    .inst-card {
        min-width: 100%;
    }
}

.location-badge {
    background: #e2e8f0;
    color: var(--primary-dark);
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    font-weight: 700;
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 1.5rem;
    width: fit-content;
}

.schedule-item {
    background: var(--white);
    border-left: 5px solid var(--accent-silver);
    border-radius: 12px;
    padding: 1.2rem 1.8rem;
    display: grid;
    grid-template-columns: 140px 1fr;
    align-items: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
    transition: var(--transition-smooth);
}

    .schedule-item:hover {
        transform: translateX(8px);
        box-shadow: 0 6px 20px rgba(0, 86, 166, 0.08);
    }

    /* Resaltado para ponentes principales */
    .schedule-item.speaker-event {
        border-left-color: var(--primary-blue);
    }

        .schedule-item.speaker-event h4 {
            color: var(--primary-dark);
            font-size: 1.15rem;
            font-weight: 700;
        }

        .schedule-item.speaker-event p {
            color: var(--primary-blue);
            font-style: italic;
            font-weight: 500;
        }

    /* Resaltado para eventos protocolares */
    .schedule-item.highlight {
        border-left-color: #d97706;
        background: #fffbe0;
    }

        .schedule-item.highlight h4 {
            color: #92400e;
        }

    /* Eventos de Receso / Box Lunch */
    .schedule-item.break-event {
        border-left-color: #10b981;
        background: #f0fdf4;
    }

        .schedule-item.break-event h4 {
            color: #065f46;
        }

.schedule-time {
    font-weight: 700;
    color: var(--primary-dark);
    font-size: 1rem;
}

@media (max-width: 600px) {
    .schedule-item {
        grid-template-columns: 1fr;
        gap: 0.4rem;
    }
}