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

:root {
    /* Vector Institute Official Brand Colors */
    --vector-blue: #313cff;        /* RGB(0, 115, 141) - Primary brand color */
    --vector-red: #Eb088a;          /* RGB(227, 22, 121) - Accent/magenta */
    --vector-grey: #202124;         /* RGB(32, 33, 36) - Text dark */
    
    /* Applied colors */
    --primary-color: var(--vector-red);
    --secondary-color: var(--vector-blue);
    --text-dark: var(--vector-grey);
    --text-gray: #5f6368;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --border-color: #dadce0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
}

.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: #000;
    color: white;
    padding: 8px;
    text-decoration: none;
}

.skip-link:focus {
    top: 0;
}

/* Header */
header {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 2rem 0;
    text-align: center;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.logos {
    margin-bottom: 1.5rem;
}

.vector-logo {
    height: 80px;
    max-width: 300px; 
}

.site-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.subtitle {
    font-size: 1.3rem;
    color: var(--text-gray);
    font-weight: 400;
}

/* Navigation */
.main-nav {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.main-nav a {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.main-nav a:hover {
    background-color: var(--bg-light);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Sections */
.content-section {
    padding: 4rem 0;
}

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

section h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--text-dark);
}

/* Hero Section */
.hero {
    padding: 4rem 0;
    text-align: center;
}

.hero h2 {
    font-size: 2.2rem;
    margin-bottom: 1.5rem;
    line-height: 1.3;
}

.authors {
    font-size: 1.1rem;
    color: var(--text-gray);
    margin: 2rem 0;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 2rem 0;
    flex-wrap: wrap;
}

.btn {
    padding: 0.75rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    text-decoration: none;
    transition: all 0.3s;
    border: 2px solid transparent;
    cursor: pointer;
    font-family: inherit;
}

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

.btn-primary:hover {
    background-color: #005a8d;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 115, 178, 0.3);
}

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

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

.lead {
    font-size: 1.15rem;
    line-height: 1.8;
    color: var(--text-gray);
    margin-top: 2rem;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

/* Challenge Grid */
.challenge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.challenge-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s, box-shadow 0.2s;
}

.challenge-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.challenge-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.challenge-card p {
    color: var(--text-gray);
    line-height: 1.7;
}

/* Findings */
.finding {
    margin-bottom: 3rem;
}

.finding h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.finding p {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-gray);
    margin-bottom: 1rem;
}

.insight-box {
    background: linear-gradient(135deg, #e3f2fd 0%, #f3e5f5 100%);
    border-left: 4px solid var(--primary-color);
    padding: 1rem 1.5rem;
    margin-top: 1rem;
    border-radius: 4px;
}

.insight-box strong {
    color: var(--primary-color);
}

/* Takeaway Grid */
.takeaway-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.takeaway-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border-top: 4px solid var(--primary-color);
    transition: all 0.3s;
}

.takeaway-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
}

.takeaway-card .number {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    width: 40px;
    height: 40px;
    line-height: 40px;
    text-align: center;
    border-radius: 50%;
    font-weight: bold;
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

.takeaway-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.75rem;
    color: var(--text-dark);
}

.takeaway-card p {
    color: var(--text-gray);
    line-height: 1.7;
}

/* Conclusion */
.conclusion-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-gray);
    margin-bottom: 2rem;
}

.conclusion-list {
    list-style: none;
    padding-left: 0;
    margin: 2rem 0;
}

.conclusion-list li {
    padding: 1rem;
    margin-bottom: 0.75rem;
    background: var(--bg-light);
    border-left: 4px solid var(--secondary-color);
    font-size: 1.05rem;
    line-height: 1.7;
}

.call-to-action {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2.5rem;
    border-radius: 12px;
    margin-top: 3rem;
}

.call-to-action h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: white;
}

.call-to-action p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.95);
}

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

.team-card {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
}

.team-card-wide {
    grid-column: 1 / -1;
}

.team-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
    color: var(--primary-color);
}

.team-card p {
    color: var(--text-gray);
    line-height: 1.6;
    font-size: 0.95rem;
}

/* Citation */
.citation-box {
    position: relative;
    background: #f5f5f5;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    margin-top: 1rem;
}

.citation-box pre {
    margin: 0;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--text-dark);
}

.copy-button {
    position: absolute;
    top: 1rem;
    right: 1rem;
    padding: 0.5rem 1rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    transition: background-color 0.2s;
}

.copy-button:hover {
    background: #005a8d;
}

/* Footer */
footer {
    background: var(--text-dark);
    color: white;
    padding: 3rem 0;
    text-align: center;
}

footer p {
    margin-bottom: 0.5rem;
}

.footer-links {
    margin-top: 1.5rem;
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.2s;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .site-title {
        font-size: 2rem;
    }

    .subtitle {
        font-size: 1.1rem;
    }

    .main-nav {
        flex-wrap: wrap;
        gap: 0.5rem;
        padding: 0.75rem 1rem;
    }

    .hero h2 {
        font-size: 1.8rem;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: stretch;
    }

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

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

    .content-section {
        padding: 2rem 0;
    }

    section h2 {
        font-size: 1.6rem;
    }

    .team-card-wide {
        grid-column: auto;
    }

    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }
}

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

    .site-title {
        font-size: 1.5rem;
    }

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