:root {
    --primary-color: #003366;
    /* Deep Blue */
    --secondary-color: #007bff;
    /* Bright Blue */
    --accent-color: #e6f2ff;
    /* Light Blue Background */
    --text-color: #333333;
    --light-text: #666666;
    --background-color: #ffffff;
    --section-bg: #f9fafb;
    --white: #ffffff;
    --green-cta: #28a745;
    --border-radius: 8px;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 50px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    text-transform: uppercase;
    font-size: 0.9rem;
    letter-spacing: 0.5px;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    border: 2px solid var(--primary-color);
}

.btn-primary:hover {
    background-color: transparent;
    color: var(--white);
    /* For hero context usually, adjust if used on white bg */
}

/* Adjust primary hover if on white background */
.section .btn-primary:hover {
    color: var(--primary-color);
}

.btn-secondary {
    background-color: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

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

/* --- Navigation --- */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    padding: 15px 0;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-color);
}

.logo img {
    height: 40px;
}

.nav-menu {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav-menu a {
    font-weight: 500;
    color: var(--text-color);
    font-size: 0.95rem;
}

.nav-menu a:hover {
    color: var(--secondary-color);
}

.btn-nav {
    background-color: var(--primary-color);
    color: var(--white) !important;
    padding: 8px 20px;
    border-radius: 20px;
}

.btn-nav:hover {
    background-color: var(--secondary-color);
}

.nav-toggle {
    display: none;
    font-size: 1.5rem;
    color: var(--primary-color);
    cursor: pointer;
}

/* --- Hero Section --- */
.hero {
    height: 100vh;
    min-height: 600px;
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    text-align: center;
    color: var(--white);
    padding-top: 80px;
    /* Offset for sticky nav */
    position: relative;
    overflow: hidden;
}

.hero-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: 1;
}

.video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 51, 102, 0.85);
    /* Adjust opacity for video visibility vs text readability */
    z-index: 2;
}

.hero-content {
    /* Ensure content stays on top of video */
    position: relative;
    z-index: 3;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.hero-subtitle {
    font-size: 1.2rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    opacity: 0.9;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
}

.hero-meta {
    display: flex;
    gap: 30px;
    font-size: 1.1rem;
    flex-wrap: wrap;
    justify-content: center;
}

.meta-item i {
    margin-right: 8px;
    color: var(--secondary-color);
}

.hero-description {
    max-width: 700px;
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 20px;
}

.hero-cta {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
}

.download-section {
    margin-top: 30px;
    width: 100%;
}

.download-buttons {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    justify-content: center;
}

.btn-download {
    padding: 12px 25px;
    border-radius: 30px;
    font-weight: 700;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    transition: var(--transition);
    font-size: 0.95rem;
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.btn-light-blue {
    background: linear-gradient(135deg, #00d2ff, #3a7bd5);
}

.btn-yellow {
    background: linear-gradient(135deg, #ffd700, #ffae00);
    color: #333;
}

.btn-orange {
    background: linear-gradient(135deg, #ff8c00, #ff4500);
}

/* --- Sections General --- */
.section {
    padding: 80px 0;
}

.section-bg {
    background-color: var(--section-bg);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.section-line {
    width: 60px;
    height: 4px;
    background-color: var(--secondary-color);
    margin: 0 auto;
    border-radius: 2px;
}

/* --- About Section --- */
.about-section {
    position: relative;
    overflow: hidden;
}

.about-section:before,
.about-section:after {
    content: '';
    position: absolute;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(0, 123, 255, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    z-index: -1;
    filter: blur(40px);
}

.about-section:before {
    top: -100px;
    left: -100px;
}

.about-section:after {
    bottom: -100px;
    right: -100px;
}

.about-container {
    max-width: 1000px;
    margin: 0 auto;
}

.about-glass-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 51, 102, 0.05);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 50px;
    text-align: center;
}

.about-glass-card p {
    text-align: justify;
    color: var(--text-color);
    margin-bottom: 20px;
}

.about-glass-card p:last-child {
    margin-bottom: 0;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-bottom: 60px;
}

.feature-item {
    background: var(--white);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    transition: var(--transition);
    border-bottom: 4px solid var(--secondary-color);
    box-shadow: var(--shadow-sm);
}

.feature-item:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.feature-item h4 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.feature-item p {
    font-size: 0.95rem;
    color: var(--light-text);
}

.venue-highlight {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 0;
    background-color: var(--white);
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    margin-top: 40px;
}

.venue-img {
    width: 100%;
    height: 100%;
    min-height: 350px;
    object-fit: cover;
}

.venue-info {
    padding: 50px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.venue-tag {
    display: inline-block;
    padding: 5px 15px;
    background: var(--accent-color);
    color: var(--primary-color);
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: 15px;
    width: fit-content;
}

.venue-info h3 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 15px;
    line-height: 1.2;
}

.venue-info p {
    font-size: 1.1rem;
    color: var(--light-text);
    margin-bottom: 25px;
}

.map-link {
    color: var(--secondary-color);
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1rem;
}

.map-link i {
    transition: transform 0.3s ease;
}

.map-link:hover i {
    transform: translateX(5px);
}

/* --- Dates Section --- */
.dates-section {
    background-color: var(--section-bg);
}

.scopus-notice {
    margin-top: 20px;
    color: #666;
    background-color: #e6f7ff;
    padding: 10px 20px;
    display: inline-block;
    border-radius: 4px;
    border-left: 4px solid var(--secondary-color);
}

.dates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.date-card {
    background: var(--white);
    padding: 30px;
    border-radius: var(--border-radius);
    text-align: center;
    box-shadow: var(--shadow-sm);
    border-top: 4px solid transparent;
    transition: var(--transition);
}

.date-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.date-card.highlight {
    border-top-color: var(--secondary-color);
    background-color: #f0f7ff;
}

.date-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.date-card h3 {
    color: var(--text-color);
    margin-bottom: 10px;
    font-size: 1.25rem;
}

.date-card p {
    color: var(--light-text);
}

.center-cta {
    text-align: center;
    margin-top: 50px;
}

.scopus-badge {
    height: 60px;
    object-fit: contain;
}

.section-header p {
    max-width: 800px;
    margin: 0 auto;
    color: var(--light-text);
    text-align: justify;
}

.publication-logos {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 30px;
    margin-top: 30px;
}

.publication-logos img {
    height: 50px;
    width: auto;
    object-fit: contain;
    filter: grayscale(100%);
    opacity: 0.6;
    transition: var(--transition);
}

.publication-logos img:hover {
    filter: grayscale(0%);
    opacity: 1;
}

.topics-highlight {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    border: 3px solid var(--primary-color);
    padding: 30px;
    border-radius: var(--border-radius);
    margin-bottom: 40px;
    position: relative;
    background-color: rgba(0, 51, 102, 0.02);
    /* Very subtle tint */
}

.text-blue {
    color: var(--secondary-color);
}

.email-link {
    color: var(--secondary-color);
    text-decoration: underline;
    font-weight: 500;
    transition: var(--transition);
}

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

/* Optional: Label for the highlighted section? User didn't ask, but it might look nice. Keeping it simple for now matching request. */

.topic-card {
    background: var(--white);
    border: 1px solid #eee;
    border-radius: var(--border-radius);
    padding: 40px 30px;
    transition: var(--transition);
}

.topic-card:hover {
    box-shadow: var(--shadow-lg);
    border-color: var(--secondary-color);
}

.topic-icon {
    font-size: 3rem;
    color: var(--secondary-color);
    margin-bottom: 25px;
}

.topic-card h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.topic-card ul {
    color: var(--light-text);
}

.topic-card ul li {
    margin-bottom: 10px;
    padding-left: 20px;
    position: relative;
    font-size: 0.95rem;
}

.topic-card ul li:before {
    content: "•";
    color: var(--secondary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

/* --- Committees Section --- */
.committees-section {
    background-color: var(--section-bg);
}

.committee-group {
    margin-bottom: 60px;
    text-align: center;
}

.committee-group h3,
.committee-column h3 {
    font-size: 1.8rem;
    color: var(--text-color);
    margin-bottom: 30px;
    position: relative;
    display: inline-block;
}

.table-title {
    font-size: 1.4rem;
    color: var(--primary-color);
    margin: 40px 0 20px;
    font-weight: 700;
    text-align: left;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
    border-left: 4px solid var(--secondary-color);
    padding-left: 15px;
}

.table-wrapper {
    max-width: 900px;
    margin: 0 auto 30px;
    overflow-x: auto;
    border-radius: 15px;
}

.glass-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 51, 102, 0.05);
    box-shadow: var(--shadow-md);
}

.futuristic-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.95rem;
}

.futuristic-table thead tr {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.futuristic-table th,
.futuristic-table td {
    padding: 15px 20px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.futuristic-table tbody tr {
    transition: var(--transition);
}

.futuristic-table tbody tr:hover {
    background: rgba(0, 123, 255, 0.05);
    transform: translateX(5px);
}

.role-cell {
    font-weight: 700;
    color: var(--primary-color);
    width: 30%;
}

.honorary-grid {
    display: flex;
    justify-content: center;
    gap: 60px;
    flex-wrap: wrap;
}

.person-card {
    text-align: center;
}

.person-card .person-img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    margin: 0 auto 20px;
    border: 5px solid var(--white);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    position: relative;
    background-color: transparent;
}

.person-card .person-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Image styling within person-card handled by img tag selector above */

.placeholder-img {
    overflow: hidden;
}

.person-card h4 {
    font-size: 1.2rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.person-card .role {
    font-size: 0.9rem;
    color: var(--light-text);
    max-width: 250px;
    margin: 0 auto;
}

.committee-split {
    display: flex;
    justify-content: center;
    gap: 80px;
    flex-wrap: wrap;
}

.committee-column {
    text-align: center;
    min-width: 300px;
}

.committee-list li {
    margin-bottom: 15px;
    font-size: 1.05rem;
    color: var(--light-text);
}

.committee-list strong {
    color: var(--primary-color);
}

/* --- Speakers Section --- */
.speakers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.speaker-card {
    background: var(--white);
    padding: 30px;
    border-radius: var(--border-radius);
    text-align: center;
    border: 1px solid #eee;
    transition: var(--transition);
}

.speaker-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.speaker-img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    margin: 0 auto 20px;
    border: 4px solid var(--accent-color);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

.speaker-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.speaker-card h4 i {
    color: var(--secondary-color);
    margin-right: 8px;
    font-size: 0.9em;
}

.speaker-card h4 {
    color: var(--primary-color);
    margin-bottom: 5px;
    font-size: 1.2rem;
}

/* --- Registration Section --- */
.registration-section {
    background-color: var(--white);
}

.fees-container {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
    margin-bottom: 60px;
}

.fee-card {
    background: var(--white);
    border: 1px solid #eee;
    padding: 40px;
    border-radius: var(--border-radius);
    text-align: center;
    width: 300px;
    box-shadow: var(--shadow-sm);
    position: relative;
    transition: var(--transition);
}



.fee-card h3 {
    margin-bottom: 20px;
    color: var(--text-color);
}

.fee-card .price {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-color);
}

.payment-info {
    max-width: 700px;
    margin: 0 auto;
    background: #f8f9fa;
    padding: 40px;
    border-radius: var(--border-radius);
    border-left: 5px solid var(--primary-color);
}

.payment-info h3 {
    margin-bottom: 20px;
    color: var(--primary-color);
}

.bank-details {
    margin-top: 20px;
    background: white;
    padding: 20px;
    border-radius: 5px;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
}

.detail-row:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.detail-row .label {
    font-weight: 600;
    color: var(--light-text);
}

.detail-row .value {
    font-family: monospace;
    font-size: 1.1rem;
    color: var(--text-color);
}

/* --- Sponsors Section --- */
.sponsors-section {
    background-color: var(--white);
    /* Can toggle with bg color if needed */
    padding-bottom: 40px;
}

.sponsors-grid {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 40px;
}

.sponsors-grid img {
    height: 80px;
    /* Standardize height */
    width: auto;
    object-fit: contain;
    filter: grayscale(100%);
    opacity: 0.7;
    transition: var(--transition);
}

.sponsors-grid img:hover {
    filter: grayscale(0%);
    opacity: 1;
}

/* --- Footer --- */
.footer {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 80px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h3 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid rgba(255, 255, 255, 0.2);
    display: inline-block;
}

.footer-col p {
    margin-bottom: 15px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    opacity: 0.9;
}

.footer-col a {
    display: block;
    margin-bottom: 10px;
    opacity: 0.8;
}

.footer-col a:hover {
    opacity: 1;
    padding-left: 5px;
}

.copyright {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    opacity: 0.6;
}

/* --- Responsive Media Queries --- */
@media (max-width: 992px) {
    .hero-title {
        font-size: 2.8rem;
    }

    .about-features {
        grid-template-columns: repeat(2, 1fr);
    }

    .venue-highlight {
        grid-template-columns: 1fr;
    }

    .venue-img {
        height: 250px;
    }

    .committee-split {
        flex-direction: column;
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .section {
        padding: 60px 0;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background-color: var(--white);
        flex-direction: column;
        padding: 40px 20px;
        transition: var(--transition);
        box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
        z-index: 100;
    }

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

    .nav-toggle {
        display: block;
    }

    .hero-title {
        font-size: 2.2rem;
    }

    .hero-meta {
        flex-direction: column;
        align-items: center;
        gap: 10px;
    }

    .hero-cta {
        flex-direction: column;
        width: 100%;
        max-width: 300px;
    }

    .btn {
        width: 100%;
    }

    .about-features {
        grid-template-columns: 1fr;
    }

    .about-glass-card {
        padding: 25px;
    }

    .topics-highlight {
        grid-template-columns: 1fr;
    }

    .speakers-grid {
        grid-template-columns: 1fr;
    }

    .fees-container {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .payment-info {
        padding: 25px;
    }

    .detail-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }

    .detail-row .value {
        font-size: 0.9rem;
        word-break: break-all;
    }

    .publication-logos {
        gap: 15px;
    }

    .publication-logos img {
        height: 35px;
    }

    .table-wrapper {
        margin-left: -15px;
        margin-right: -15px;
        padding: 0 15px;
    }

    .futuristic-table th,
    .futuristic-table td {
        padding: 12px 10px;
        font-size: 0.85rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.8rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .download-buttons {
        flex-direction: column;
        width: 100%;
    }

    .btn-download {
        width: 100%;
        justify-content: center;
    }

    .venue-info {
        padding: 30px 20px;
    }

    .venue-info h3 {
        font-size: 1.5rem;
    }
}