/* Modern Design System for I3CSET-2026 */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;600;700&display=swap');

:root {
    --primary: #0f172a;
    --accent: #dc2626;
    --accent-glow: #dc262680;
    --secondary: #f97316;
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --bg: #020617;
    --footer-bg: #000000;
    --glass: rgba(15, 23, 42, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --header-overlay: rgba(2, 6, 23, 0.8);
}

*,
::before,
::after {
    box-sizing: border-box;
}

/* Utilities */
.container {
    width: 100%;
    margin-left: auto;
    margin-right: auto;
}

.mx-auto {
    margin-left: auto;
    margin-right: auto;
}

.px-4 {
    padding-left: 1rem;
    padding-right: 1rem;
}

.py-12 {
    padding-top: 3rem;
    padding-bottom: 3rem;
}

.max-w-7xl {
    max-width: 80rem;
}

.flex {
    display: flex;
}

.flex-wrap {
    flex-wrap: wrap;
}

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

.gap-4 {
    gap: 1rem;
}

.gap-8 {
    gap: 2rem;
}

body.light-mode {
    --primary: #f8fafc;
    --accent: #ef4444;
    --accent-glow: #ef444440;
    --secondary: #ea580c;
    --text: #0f172a;
    --text-muted: #475569;
    --bg: #f8fafc;
    --footer-bg: #f1f5f9;
    --glass: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(0, 0, 0, 0.08);
    --header-overlay: rgba(248, 250, 252, 0.85);
}

body.light-mode .modern-nav {
    background: rgba(254, 242, 242, 0.95);
    border-bottom: 1px solid rgba(220, 38, 38, 0.15);
}

* {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, backdrop-filter 0.3s ease, box-shadow 0.3s ease;
}

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    margin: 0;
    overflow-x: hidden;
}

/* Glassmorphism Header */
.modern-header {
    background: linear-gradient(var(--header-overlay), var(--header-overlay)), url('../images/hero-bg.png');
    background-size: cover;
    background-position: center;
    min-height: 60vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 2rem;
    position: relative;
    border-bottom: 1px solid var(--glass-border);
}

.modern-header::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 100px;
    background: linear-gradient(to top, var(--bg), transparent);
}

.hero-content {
    backdrop-filter: blur(10px);
    background: var(--glass);
    padding: 3rem 2rem;
    border-radius: 20px;
    border: 1px solid var(--glass-border);
    width: 95%; /* Fluid width */
    max-width: 900px;
    margin: 0 auto;
    animation: fadeInUp 1s ease-out;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

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

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

.conference-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, var(--accent), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.conference-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

.quick-info {
    display: flex;
    gap: 2rem;
    justify-content: center;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text);
}

.info-item i {
    color: var(--accent);
}

/* Navigation Ribbon */
.modern-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--glass);
    backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--glass-border);
    padding: 0.75rem 0;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.nav-brand-group {
    display: flex;
    align-items: center;
}

.nav-logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    background: white;
    padding: 6px 14px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-logo-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.nav-logo-img {
    height: 40px;
    width: auto;
    display: block;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    padding: 0.5rem 0;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: var(--transition);
}

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

.nav-links a:hover,
.nav-links a.active {
    color: var(--accent);
}

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

/* Mobile Menu Toggle Styles */
.mobile-menu-toggle {
    display: none;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    color: var(--text);
    width: 40px;
    height: 40px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.2rem;
    transition: var(--transition);
    align-items: center;
    justify-content: center;
    z-index: 1001;
}

.mobile-menu-toggle .hide-icon {
    display: none;
}

.mobile-menu-toggle.active .show-icon {
    display: none;
}

.mobile-menu-toggle.active .hide-icon {
    display: block;
}

/* Modern Ticker */
#news-ticker-container {
    background: var(--primary);
    color: var(--text);
    padding: 8px 0;
    overflow: hidden;
    white-space: nowrap;
    position: relative;
    z-index: 1001;
    border-bottom: 1px solid var(--glass-border);
}

.ticker-content {
    display: inline-block;
    padding-left: 100%;
    animation: ticker 30s linear infinite;
}

.ticker-item {
    display: inline-block;
    margin-right: 50px;
    font-weight: 500;
}

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

.ticker-item a {
    color: var(--secondary);
    text-decoration: none;
}

.ticker-item a:hover {
    text-decoration: underline;
}

@keyframes ticker {
    0% {
        transform: translateX(0);
    }

    100% {
        transform: translateX(-100%);
    }
}

/* Sections */
.main-content {
    max-width: 1400px;
    margin: 4rem auto;
    display: grid;
    grid-template-columns: 1.6fr 1.4fr;
    gap: 3rem;
    padding: 0 1.5rem;
}

.section-card {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 1.25rem;
    margin-bottom: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    overflow: hidden;
}

.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text);
}

.section-title::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--glass-border);
}

/* Date Cards */
.date-list {
    list-style: none;
    padding: 0;
}

.date-card {
    display: flex;
    align-items: flex-end;
    flex-wrap: nowrap;
    /* Align to the bottom of the line */
    padding: 0.85rem 0.4rem;
    /* Add horizontal padding to prevent edge touching */
    border-bottom: 1px solid var(--glass-border);
    transition: var(--transition);
    color: var(--text);
    gap: 6px;
    /* Consistent gap */
    width: 100%;
    box-sizing: border-box;
}

.date-card .label {
    font-weight: 600;
    flex: 1;
    min-width: 80px;
    /* Take all available space */
    display: flex;
    align-items: flex-end;
    gap: 0.4rem;
    font-size: 0.82rem;
    /* Slightly smaller for sidebar fit */
}

/* The dotted line now sits precisely between label and value */
.date-card .spacer {
    flex: 1;
    border-bottom: 2px dotted var(--glass-border);
    margin: 0 4px;
    margin-bottom: 4px;
    /* Move dots up to align with text */
    opacity: 0.3;
}

.date-card .label i {
    color: var(--accent);
    width: 18px;
    text-align: center;
    margin-bottom: 1px;
}

.date-card .value {
    color: var(--accent);
    font-weight: 700;
    font-size: 0.85rem;
    text-align: right;
    white-space: nowrap;
    /* Keep the date on one line */
}

.date-card:hover {
    background: rgba(var(--accent), 0.05);
    border-radius: 8px;
}

.date-value.closed {
    color: var(--text-muted) !important;
    text-decoration: line-through;
    opacity: 0.7;
}

/* Buttons */
.btn-primary {
    background: var(--accent);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: 0 4px 6px -1px var(--accent-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 15px -3px var(--accent-glow);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--accent);
    color: var(--accent);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
}

.btn-outline:hover {
    background: var(--accent);
    color: white;
    transform: translateY(-2px);
}

/* Footer */
footer {
    background: var(--footer-bg);
    padding: 4rem 1.5rem;
    border-top: 1px solid var(--glass-border);
    color: var(--text);
}

.footer-grid {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 3rem;
}

.footer-section h4 {
    color: var(--text);
    margin-bottom: 1.5rem;
    text-transform: uppercase;
    font-weight: 700;
}

.footer-section ul {
    list-style: none;
    padding: 0;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: var(--text-muted);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--accent);
}

.footer-section ul i {
    width: 25px;
    text-align: center;
    color: var(--accent);
    margin-right: 0.5rem;
    font-size: 1.1rem;
}

/* Theme Toggle Button */
.theme-toggle {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    color: var(--text);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.1rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.theme-toggle:hover {
    background: var(--accent);
    color: white;
    transform: scale(1.1) rotate(15deg);
}

.light-mode-icon {
    display: none;
}

body.light-mode .dark-mode-icon {
    display: none;
}

body.light-mode .light-mode-icon {
    display: block;
}

/* Track Accordion Styles */
.track-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 2rem;
}

.track-item {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    overflow: hidden;
    transition: var(--transition);
}

.track-item summary {
    padding: 1.25rem;
    cursor: pointer;
    font-weight: 700;
    list-style: none;
    /* Hide default arrow */
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text);
    background: rgba(255, 255, 255, 0.02);
}

.track-item summary::-webkit-details-marker {
    display: none;
}

.track-item summary::after {
    content: '\f078';
    /* fa-chevron-down */
    font-family: 'Font Awesome 5 Free';
    font-weight: 900;
    font-size: 0.8rem;
    color: var(--accent);
    transition: transform 0.3s ease;
}

.track-item[open] summary::after {
    transform: rotate(180deg);
}

.track-item[open] {
    border-color: var(--accent);
    box-shadow: 0 0 15px var(--accent-glow);
}

.track-content {
    padding: 1.25rem;
    padding-top: 0;
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
    border-top: 1px solid var(--glass-border);
    margin-top: 0.5rem;
    padding-top: 1rem;
}

.track-content ul {
    list-style: disc;
    padding-left: 1.5rem;
    margin-top: 0.5rem;
}

/* Responsive Adjustments */
@media (max-width: 1200px) {
    .nav-links {
        gap: 1rem;
    }

    .nav-links a {
        font-size: 0.8rem;
    }

    .main-content {
        gap: 2rem;
    }
}

@media (max-width: 1024px) {
    .conference-title {
        font-size: 2.75rem;
    }

    .hero-content {
        padding: 2rem;
    }

    .main-content {
        grid-template-columns: 1fr;
        margin: 2rem auto;
    }

    .sidebar {
        order: 2;
    }

    .content-area {
        order: 1;
    }
}

@media (max-width: 768px) {
    .modern-header {
        min-height: 50vh;
        padding: 1rem;
    }

    .conference-title {
        font-size: 2.25rem;
    }

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

    .quick-info {
        gap: 1rem;
    }

    .info-item {
        font-size: 0.9rem;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%) scale(0.9);
        width: 90%;
        max-width: 380px;
        height: auto;
        max-height: 85vh;
        background: var(--glass);
        backdrop-filter: blur(25px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 0.5rem;
        padding: 2.5rem 1.5rem;
        border-radius: 24px;
        border: 1px solid var(--glass-border);
        transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
        z-index: 1000;
        box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
        opacity: 0;
        visibility: hidden;
        overflow-y: auto;
    }

    .nav-links.mobile-menu-active {
        opacity: 1;
        visibility: visible;
        transform: translate(-50%, -50%) scale(1);
    }

    .nav-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(0, 0, 0, 0.5);
        backdrop-filter: blur(4px);
        z-index: 999;
        /* Just below the menu */
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }

    .nav-overlay.active {
        opacity: 1;
        visibility: visible;
    }

    .nav-links a {
        font-size: 1.1rem;
        width: 100%;
        text-align: center;
        padding: 0.75rem;
        border-radius: 12px;
        transition: var(--transition);
    }

    .nav-links a:hover,
    .nav-links a.active {
        background: rgba(220, 38, 38, 0.1);
        color: var(--accent);
    }

    .highlight-grid {
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
        gap: 1rem;
    }

    .h-card {
        padding: 1rem;
    }

    .h-card i {
        font-size: 1.8rem;
    }

    .h-card h3 {
        font-size: 0.95rem;
    }

    .footer-grid {
        gap: 2rem;
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-section h4::after {
        left: 50%;
        transform: translateX(-50%);
    }

    /* Gallery Mobile */
    .gallery-track {
        width: calc(280px * 22);
    }

    .gallery-track:hover {
        animation-play-state: paused;
    }

    .gallery-item {
        width: 280px;
        height: 180px;
    }

    @keyframes scroll {
        0% {
            transform: translateX(0);
        }

        100% {
            transform: translateX(calc(-280px * 11));
        }
    }
}

@media (max-width: 480px) {
    .conference-title {
        font-size: 1.75rem;
    }

    .hero-logo {
        width: 120px;
    }

    .btn-primary,
    .btn-outline {
        width: 100%;
    }

    .hero-content div[style*="flex"] {
        flex-direction: column;
    }

    .section-title {
        font-size: 1.4rem;
    }

    .welcome-card {
        padding-left: 1rem;
    }

    .date-card .label {
        font-size: 0.75rem;
    }

    .date-card .value {
        font-size: 0.8rem;
    }
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--accent);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 4px 15px var(--accent-glow);
    transition: var(--transition);
    opacity: 0;
    visibility: hidden;
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-5px);
    background: var(--secondary);
}

@media (max-width: 768px) {
    .back-to-top {
        bottom: 1.5rem;
        right: 1.5rem;
        width: 45px;
        height: 45px;
    }
}