:root {
    --primary-color: #1a365d;
    --secondary-color: #3182ce;
    --accent-color: #ed8936;
    --light-bg: #f7fafc;
    --dark-bg: #1a202c;
    --text-color: #2d3748;
    --text-light: #718096;
    --white: #ffffff;
    --spacing: 2rem;
    --radius: 12px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing);
}

/* Typography */
h1, h2, h3, h4 {
    line-height: 1.2;
    font-weight: 700;
}

h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
}

h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

p {
    margin-bottom: 1rem;
}

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

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background: #dd6b20;
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

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

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

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

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

.btn-nav {
    background: var(--accent-color);
    color: var(--white);
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.btn-nav:hover {
    background: #dd6b20;
    color: var(--white);
}

/* Navigation */
.navbar {
    background: var(--primary-color);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--white);
    letter-spacing: 0.05em;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

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

/* Hero Section */
.hero {
    min-height: 100vh;
    background: linear-gradient(135deg, var(--primary-color) 0%, #2c5282 100%);
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    padding: 120px var(--spacing) 60px;
    gap: 4rem;
}

.hero-eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 1rem;
}

.hero-content h1 {
    font-size: 3.5rem;
    color: var(--white);
    margin-bottom: 1.5rem;
    line-height: 1.1;
}

.hero-content h1 .highlight {
    color: var(--accent-color);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    gap: 3rem;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-color);
}

.stat-label {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-image img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
}

/* Sections */
.section {
    padding: 5rem 0;
}

.section-title {
    text-align: center;
    margin-bottom: 1rem;
}

.section-intro {
    text-align: center;
    font-size: 1.125rem;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto 3rem;
}

.bg-light {
    background: var(--light-bg);
}

.bg-dark {
    background: var(--dark-bg);
}

/* Challenge Section */
.challenge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.challenge-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    position: relative;
    transition: transform 0.2s, box-shadow 0.2s;
}

.challenge-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.challenge-number {
    position: absolute;
    top: -10px;
    left: 20px;
    background: var(--accent-color);
    color: var(--white);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1rem;
}

.challenge-card h3 {
    margin-top: 0.5rem;
    margin-bottom: 0.75rem;
}

.challenge-card p {
    color: var(--text-light);
    margin-bottom: 0;
}

/* Quote Block */
.quote-block {
    text-align: center;
    padding: 3rem 0;
}

.quote-block blockquote {
    font-size: 1.75rem;
    font-style: italic;
    color: var(--white);
    max-width: 800px;
    margin: 0 auto 1rem;
    line-height: 1.4;
}

.quote-block cite {
    color: var(--accent-color);
    font-style: normal;
    font-weight: 500;
}

/* Research Section */
.research-grid {
    display: flex;
    flex-direction: column;
    gap: 4rem;
}

.research-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.research-item.reverse {
    direction: rtl;
}

.research-item.reverse > * {
    direction: ltr;
}

.research-image img {
    width: 100%;
    height: auto;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.research-content h3 {
    font-size: 1.75rem;
    margin-bottom: 1rem;
}

.framework-list {
    list-style: none;
    margin-top: 1rem;
}

.framework-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e2e8f0;
}

.framework-list li:last-child {
    border-bottom: none;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    text-align: center;
}

.cta-content {
    max-width: 700px;
    margin: 0 auto;
}

.cta-content h2 {
    color: var(--white);
    margin-bottom: 1.5rem;
}

.cta-content p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
}

.cta-content .btn {
    margin: 1.5rem 0;
}

.cta-note {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 3fr 2fr;
    gap: 3rem;
    align-items: start;
}

.about-content h3 {
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.publications {
    list-style: none;
}

.publications li {
    padding: 0.75rem 0;
    border-bottom: 1px solid #e2e8f0;
}

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

.rounded-image {
    border-radius: var(--radius);
    width: 100%;
    height: auto;
    box-shadow: var(--shadow);
}

/* Help Section */
.help-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.help-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
}

.help-card h3 {
    margin-bottom: 1rem;
}

.help-card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

/* Team Section */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.team-category {
    background: var(--white);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.team-category h3 {
    color: var(--secondary-color);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--accent-color);
}

.team-category ul {
    list-style: none;
}

.team-category li {
    padding: 0.4rem 0;
    font-size: 0.95rem;
    color: var(--text-color);
    border-bottom: 1px solid #edf2f7;
}

.team-category li:last-child {
    border-bottom: none;
}

.team-category li strong {
    color: var(--primary-color);
}

/* Footer */
footer {
    background: var(--primary-color);
    color: var(--white);
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 1.5rem;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    margin-top: 0.5rem;
    font-size: 0.875rem;
}

.footer-nav {
    display: flex;
    gap: 2rem;
}

.footer-nav a {
    color: rgba(255, 255, 255, 0.7);
    transition: color 0.2s;
}

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

.footer-copyright {
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        min-height: auto;
        padding-top: 100px;
    }

    .hero-content h1 {
        font-size: 2.75rem;
    }

    .hero-subtitle {
        margin: 0 auto 2rem;
    }

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

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

    .hero-image {
        order: -1;
        max-width: 500px;
        margin: 0 auto;
    }

    .research-item,
    .research-item.reverse {
        grid-template-columns: 1fr;
        direction: ltr;
    }

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

    .about-image {
        order: -1;
        max-width: 400px;
    }
}

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

    .btn-nav {
        display: none;
    }

    .hero-content h1 {
        font-size: 2.25rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

    h2 {
        font-size: 2rem;
    }

    .section {
        padding: 3rem 0;
    }

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

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

    .footer-content {
        flex-direction: column;
        gap: 2rem;
        text-align: center;
    }

    .footer-nav {
        flex-wrap: wrap;
        justify-content: center;
    }

    .quote-block blockquote {
        font-size: 1.25rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .hero-content h1 {
        font-size: 1.875rem;
    }

    .hero-cta {
        flex-direction: column;
    }

    .btn-large {
        width: 100%;
        text-align: center;
    }
}

/* ── Page Header (for standalone pages) ────────────────────────── */

.page-header {
    padding-top: 6rem;
    padding-bottom: 1rem;
}

/* ── Recent Activity / News Section ────────────────────────────── */

.activity-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.activity-grid--full {
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
}

.activity-card {
    background: var(--white);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border-left: 4px solid var(--accent-color);
    transition: transform 0.2s, box-shadow 0.2s;
}

.activity-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.activity-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
    font-size: 0.85rem;
}

.activity-type {
    display: inline-block;
    padding: 0.1rem 0.3rem;
    border-radius: 3px;
    font-weight: 600;
    font-size: 0.55rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.activity-type--publication { background: #ebf8ff; color: #2b6cb0; }
.activity-type--event       { background: #fefcbf; color: #975a16; }
.activity-type--media       { background: #fed7e2; color: #97266d; }
.activity-type--milestone   { background: #c6f6d5; color: #276749; }

.activity-meta time {
    color: var(--text-light);
}

.activity-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.activity-card h3 a {
    color: var(--text-color);
    text-decoration: none;
}

.activity-card h3 a:hover {
    color: var(--secondary-color);
}

.activity-card p {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 0;
    line-height: 1.5;
}

.activity-more {
    text-align: center;
    margin-top: 2rem;
}

/* ── Publications Gallery (full page) ──────────────────────────── */

.pub-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.pub-card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: transform 0.2s, box-shadow 0.2s;
}

.pub-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.pub-card-preview {
    position: relative;
    aspect-ratio: 8.5 / 5;
    overflow: hidden;
    background: #f1f5f9;
}

.pub-card-preview > img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top;
}

.pub-card-overlay {
    position: absolute;
    bottom: 0.5rem;
    right: 0.5rem;
}

.journal-badge {
    height: 22px;
    background: white;
    padding: 2px 4px;
    border-radius: 3px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.15);
}

.pub-card-info {
    padding: 1.25rem;
}

.pub-card-info h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.pub-authors {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 0.25rem;
}

.pub-meta {
    font-size: 0.8rem;
    color: var(--secondary-color);
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.pub-blurb {
    font-size: 0.9rem;
    color: var(--text-light);
    line-height: 1.5;
}

.pub-card-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.btn-small {
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
}

/* ── Publications Gallery Compact (homepage) ───────────────────── */

.pub-gallery-compact {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.25rem;
    margin-top: 1rem;
}

.pub-card-compact {
    display: flex;
    flex-direction: column;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    transition: transform 0.2s, box-shadow 0.2s;
}

.pub-card-compact:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.pub-card-compact-preview {
    position: relative;
    aspect-ratio: 8.5 / 5;
    overflow: hidden;
    background: #f1f5f9;
}

.pub-card-compact-preview .pub-thumb {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top;
}

.pub-card-compact-preview .pub-journal-logo {
    position: absolute;
    bottom: 0.4rem;
    right: 0.4rem;
    height: 22px;
    background: white;
    padding: 2px 4px;
    border-radius: 3px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.15);
}

.pub-card-compact-title {
    display: block;
    padding: 0.75rem 0.75rem 0.25rem;
    font-size: 0.85rem;
    font-weight: 600;
    line-height: 1.3;
    color: var(--text-color);
}

.pub-card-compact-meta {
    display: block;
    padding: 0 0.75rem 0.75rem;
    font-size: 0.75rem;
    color: var(--secondary-color);
    font-weight: 600;
}

/* ── Responsive: New Sections ──────────────────────────────────── */

@media (max-width: 768px) {
    .activity-grid {
        grid-template-columns: 1fr;
    }

    .pub-gallery {
        grid-template-columns: 1fr;
    }

    .pub-gallery-compact {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .pub-gallery-compact {
        grid-template-columns: 1fr;
    }

    .activity-grid--full {
        grid-template-columns: 1fr;
    }
}