/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #002145;
    --secondary-color: #57767C;
    --accent-color: #40B4E5;
    --accent-hover: #6EC4E8;
    --accent-light: #97D4E9;
    --bg-color: #ffffff;
    --bg-light: #F1FBFE;
    --bg-pink: #FFF2F2;
    --bg-green: #F2FFF2;
    --border-color: #e0e0e0;
    --text-light: #666666;
    --text-dark: #002145;
    --fall-brown: #C87D62;
    --turquoise: #57767C;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1.5rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --max-width: 1400px;
    --border-radius: 8px;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Figtree', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
    font-size: 18px;
    line-height: 1.7;
    color: var(--primary-color);
    background-color: var(--bg-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: 'DM Serif Text', Georgia, serif;
    font-weight: 400;
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

h1 {
    font-size: 2.75rem;
    margin-bottom: var(--spacing-md);
}

h2 {
    font-size: 2.25rem;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: 1.625rem;
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

p {
    margin-bottom: var(--spacing-sm);
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Full width wrapper for header and footer */
.navbar .container,
.footer-wrapper {
    max-width: 100%;
    width: 100%;
    padding: 0 var(--spacing-md);
}

/* Header and Navigation */
.site-header {
    background-color: var(--primary-color);
    border-bottom: none;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.navbar {
    padding: var(--spacing-sm) 0;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-md);
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.navbar-menu {
    margin-left: auto;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    color: white;
}

.cvpr-logo {
    height: 45px;
    width: auto;
    flex-shrink: 0;
}

/* Hide mobile logo on desktop */
.mobile-logo {
    display: none;
}

.site-title {
    font-family: 'DM Serif Text', serif;
    font-size: 1.5rem;
    font-weight: 400;
    color: white;
}

.navbar-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
    align-items: center;
}

.navbar-menu a {
    color: white;
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    position: relative;
}

.navbar-menu a:hover {
    color: var(--accent-light);
}

.navbar-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-light);
    transition: width 0.3s ease;
}

.navbar-menu a:hover::after {
    width: 100%;
}

/* Hamburger Menu Button */
.hamburger-menu {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 30px;
    height: 30px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 101;
    position: relative;
}

.hamburger-line {
    width: 100%;
    height: 3px;
    background-color: white;
    border-radius: 2px;
    transition: all 0.3s ease;
}

.hamburger-menu[aria-expanded="true"] .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.hamburger-menu[aria-expanded="true"] .hamburger-line:nth-child(2) {
    opacity: 0;
}

.hamburger-menu[aria-expanded="true"] .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* Main Content */
.main-content {
    min-height: calc(100vh - 200px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--turquoise) 100%);
    color: white;
    padding: var(--spacing-md) 0;
    text-align: center;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    color: white;
    font-family: 'DM Serif Text', serif;
    font-weight: 400;
}

.hero-meta {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-md);
    flex-wrap: wrap;
}

.hero-meta-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
}

.hero-meta-item i {
    color: white;
}

/* Sections */
.section {
    padding: 0;
}

/* Full-width sections with background colors */
.section[style*="background-color"] {
    margin-left: calc(-50vw + 50%);
    margin-right: calc(-50vw + 50%);
    width: 100vw;
    padding: var(--spacing-md) 0;
    box-sizing: border-box;
}

.section[style*="background-color"] .container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.section-bg {
    width: 100%;
    padding: var(--spacing-lg) 0;
    margin: 0;
}

.section-bg .container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.section-title {
    text-align: center;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.section-content {
    max-width: 1100px;
    margin: 0 auto;
}

/* Abstract */
.abstract {
    background-color: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    margin: var(--spacing-lg) 0;
}

.abstract p {
    color: var(--text-dark);
}

/* Announcements */
.announcements-list {
    list-style: disc;
    padding-left: var(--spacing-md);
    margin: var(--spacing-md) 0;
}

.announcements-list li {
    padding: var(--spacing-xs) 0;
    color: var(--text-dark);
    line-height: 1.6;
}

/* Topics Grid */
.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
}

.topic-card {
    background-color: var(--bg-light);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius);
    border: 1px solid var(--accent-light);
}

.topic-card h3 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 0;
    font-size: 1.375rem;
}

.topic-number {
    display: inline-block;
    width: 28px;
    height: 28px;
    background-color: var(--primary-color);
    color: white;
    border-radius: 50%;
    text-align: center;
    line-height: 28px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-right: var(--spacing-xs);
    font-family: 'Figtree', sans-serif;
}

/* Speakers */
.speakers-section {
    background-color: var(--bg-color);
    width: 100%;
    padding: var(--spacing-md) 0;
    margin: 0;
}

.speakers-grid {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
    justify-content: center;
}

.speaker-card {
    background-color: var(--bg-color);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 33, 69, 0.08);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 220px;
}

.speaker-photo {
    width: 140px;
    height: 140px;
    max-width: 100%;
    border-radius: 50%;
    object-fit: cover;
    margin: 0 auto var(--spacing-sm);
    display: block;
    border: 3px solid var(--primary-color);
    flex-shrink: 0;
}

.speaker-name {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
    font-family: 'DM Serif Text', serif;
}

.speaker-affiliation {
    font-size: 0.9rem;
    color: var(--text-light);
    line-height: 1.5;
    font-style: italic;
}

.speaker-website {
    display: inline-block;
    margin-top: var(--spacing-xs);
    font-size: 0.8rem;
    color: var(--accent-color);
    font-weight: 500;
    transition: color 0.2s ease;
}

.speaker-website:hover {
    color: var(--accent-hover);
}

/* Organizers */
.organizers-section {
    background-color: var(--bg-light);
    width: 100%;
    padding: var(--spacing-md) 0;
    margin: 0;
}

.organizers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.organizer-card {
    background-color: var(--bg-color);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 33, 69, 0.08);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.organizer-photo {
    width: 140px;
    height: 140px;
    max-width: 100%;
    border-radius: 50%;
    object-fit: cover;
    margin: 0 auto var(--spacing-sm);
    display: block;
    border: 3px solid var(--accent-light);
    flex-shrink: 0;
}

.organizer-name {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
    font-family: 'DM Serif Text', serif;
}

.organizer-affiliation {
    font-size: 0.9rem;
    color: var(--text-light);
    line-height: 1.5;
    font-style: italic;
}

.organizer-website {
    display: inline-block;
    margin-top: var(--spacing-xs);
    font-size: 0.8rem;
    color: var(--accent-color);
    font-weight: 500;
    transition: color 0.2s ease;
}

.organizer-website:hover {
    color: var(--accent-hover);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--accent-color);
    color: white;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: background-color 0.2s ease, transform 0.2s ease;
    border: none;
    cursor: pointer;
    text-decoration: none;
}

.btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
    color: white;
}

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

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

/* Challenge Section */
.challenge-hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--turquoise) 100%);
    color: white;
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.challenge-hero h1,
.challenge-hero h2 {
    color: white;
}

.challenge-figure {
    max-width: 100%;
    margin: var(--spacing-lg) 0;
    text-align: center;
}

.challenge-figure img {
    max-width: 100%;
    height: auto;
}

.challenge-links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin: var(--spacing-lg) 0;
    justify-content: center;
}

.challenge-links .btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* Timeline */
.timeline {
    list-style: none;
    padding: 0;
    margin: var(--spacing-lg) 0;
}

.timeline-item {
    padding: var(--spacing-sm) 0;
    border-left: 2px solid var(--border-color);
    padding-left: var(--spacing-md);
    margin-left: var(--spacing-sm);
    position: relative;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -6px;
    top: var(--spacing-sm);
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--accent-color);
}

.timeline-date {
    font-weight: 600;
    color: var(--primary-color);
}

/* Footer */
.site-footer {
    background-color: var(--primary-color);
    color: white;
    padding: var(--spacing-lg) 0;
}

.footer-wrapper {
    width: 100%;
    padding: var(--spacing-lg) 0;
}

.footer-wrapper .container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
}

.footer-logo {
    display: flex;
    align-items: center;
}

.footer-cvpr-logo {
    height: 60px;
    width: auto;
    opacity: 0.9;
}

.footer-section {
    display: flex;
    align-items: center;
}

.footer-section h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-sm);
    color: white;
    font-family: 'DM Serif Text', serif;
}

.footer-section p {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--spacing-xs);
}

.footer-section a {
    color: var(--accent-light);
    transition: color 0.2s ease;
    font-size: 1.125rem;
}

.footer-section a:hover {
    color: white;
}

.social-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--accent-light);
    transition: color 0.2s ease;
}

.social-link:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.copyright {
    text-align: center;
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.7);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .navbar .container {
        flex-wrap: nowrap;
        position: relative;
    }

    /* Show hamburger menu on mobile */
    .hamburger-menu {
        display: flex;
    }

    /* Hide menu by default on mobile */
    .navbar-menu {
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        background-color: var(--primary-color);
        flex-direction: column;
        align-items: flex-start;
        gap: 0;
        padding: var(--spacing-sm) var(--spacing-md);
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease, padding 0.3s ease;
        z-index: 100;
    }

    /* Show menu when active */
    .navbar-menu.active {
        max-height: 400px;
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .navbar-menu li {
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .navbar-menu li:last-child {
        border-bottom: none;
    }

    .navbar-menu a {
        display: block;
        padding: var(--spacing-sm) 0;
        width: 100%;
    }

    .navbar-menu a::after {
        display: none;
    }

    .site-title {
        font-size: 1.25rem;
    }

    /* Keep logo visible in mobile navbar */
    .navbar-brand .cvpr-logo {
        height: 35px;
    }

    /* Hide mobile logo in hero section */
    .mobile-logo {
        display: none;
    }

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

    .speakers-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: var(--spacing-sm);
    }

    .speaker-card {
        padding: var(--spacing-sm);
        min-width: 0;
    }

    .speaker-photo {
        width: 100px;
        max-width: calc(100% - 16px);
        height: 100px;
        margin: 0 auto var(--spacing-xs);
    }

    .speaker-name {
        font-size: 1.125rem;
    }

    .speaker-affiliation {
        font-size: 0.9rem;
    }

    .organizers-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: var(--spacing-sm);
    }

    .organizer-card {
        padding: var(--spacing-sm);
        min-width: 0;
    }

    .organizer-photo {
        width: 100px;
        max-width: calc(100% - 16px);
        height: 100px;
        margin: 0 auto var(--spacing-xs);
    }

    .organizer-name {
        font-size: 1.125rem;
    }

    .organizer-affiliation {
        font-size: 0.9rem;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

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

    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.75rem;
    }
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-lg {
    margin-top: var(--spacing-lg);
}

.mb-lg {
    margin-bottom: var(--spacing-lg);
}

.highlight-box {
    background-color: var(--bg-light);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin: var(--spacing-md) 0;
}

.highlight-box h3 {
    color: var(--primary-color);
}