/* ============================================
   GLOBAL STYLES & VARIABLES
   ============================================ */

:root {
    /* Colors - Metropolyst theme (matching presentation) */
    --color-primary: #23373b;      /* Dark teal - primary text/headers */
    --color-accent: #008080;       /* Teal - accents and buttons */
    --color-secondary: #e3f2fd;    /* Light blue - backgrounds */
    --color-orange: #ff9800;       /* Orange - highlights */
    --color-success: #10b981;      /* Green - available badges */
    
    /* Backgrounds */
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;       /* Light gray background */
    --bg-tertiary: #e8f4f8;        /* Light blue background */
    --bg-card: #ffffff;
    
    /* Text */
    --text-primary: #23373b;       /* Dark teal for consistency */
    --text-secondary: #666666;
    --text-muted: #999999;
    
    /* Borders */
    --border-color: #e0e0e0;
    --border-radius: 8px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(35, 55, 59, 0.08);
    --shadow-md: 0 2px 8px rgba(35, 55, 59, 0.12);
    --shadow-lg: 0 8px 16px rgba(35, 55, 59, 0.16);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
}

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

/* ============================================
   NAVIGATION
   ============================================ */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    padding: 1rem 0;
}

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

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    font-size: 1.25rem;
    color: var(--color-primary);
}

.nav-icon {
    font-size: 1.75rem;
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color var(--transition-fast);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.nav-github {
    padding: 0.5rem 1rem;
    background: var(--color-primary);
    color: white !important;
    border-radius: 6px;
    transition: background var(--transition-fast);
}

.nav-github:hover {
    background: var(--color-accent);
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    padding: 7rem 0 3rem;
    background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
    margin-top: 60px;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: var(--color-success);
    color: white;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    letter-spacing: 0.5px;
}

.hero-title {
    font-size: 2.75rem;
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-primary);
    margin-bottom: 0.75rem;
}

.hero-subtitle {
    font-size: 1.35rem;
    font-weight: 400;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    line-height: 1.4;
}

.hero-abstract {
    font-size: 1.0625rem;
    color: var(--text-secondary);
    line-height: 1.75;
    margin-bottom: 2.5rem;
    text-align: justify;
    padding: 1.75rem;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--color-accent);
}

.hero-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    padding: 1.25rem 1.75rem;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
}

.meta-item {
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

.meta-item strong {
    color: var(--color-primary);
    font-weight: 600;
}

/* ============================================
   SECTION STYLES
   ============================================ */

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-primary);
    text-align: center;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ============================================
   DELIVERABLES SECTION
   ============================================ */

.deliverables {
    padding: var(--spacing-lg) 0;
    background: var(--bg-secondary);
}

.deliverables .container {
    max-width: 1280px;
}

.deliverables-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.25rem;
}

@media (max-width: 1200px) {
    .deliverables-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
}

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

.deliverable-card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
    display: flex;
    flex-direction: column;
}

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

.card-header {
    background: var(--color-primary);
    color: white;
    padding: 1.25rem 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.75rem;
    min-height: 70px;
}

.card-header h3 {
    font-size: 1.125rem;
    font-weight: 600;
    line-height: 1.3;
    white-space: nowrap;
}

.card-badge {
    padding: 0.375rem 0.75rem;
    border-radius: 50px;
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    white-space: nowrap;
    flex-shrink: 0;
}

.card-badge.available {
    background: var(--color-success);
}

.card-badge.upcoming {
    background: var(--color-orange);
}

.card-content {
    padding: 1.25rem 1rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.card-date {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-bottom: 0.625rem;
    font-weight: 500;
}

.card-description {
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    line-height: 1.5;
    font-size: 0.9375rem;
    flex: 1;
}

.card-downloads {
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    padding: 0.625rem 0.875rem;
    background: var(--color-accent);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.875rem;
    transition: background var(--transition-fast), transform var(--transition-fast);
}

.download-btn:hover {
    background: var(--color-primary);
    transform: translateX(2px);
}

.download-btn img,
.download-btn svg {
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}

.download-btn.disabled,
.card-downloads.disabled .download-btn {
    background: var(--border-color);
    color: var(--text-muted);
    cursor: not-allowed;
    pointer-events: none;
}

/* ============================================
   TEAM SECTION
   ============================================ */

.team {
    padding: var(--spacing-lg) 0;
    background: var(--bg-primary);
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
    max-width: 800px;
    margin: 0 auto;
}

.team-card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    padding: 2rem;
    text-align: center;
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

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

.team-image-placeholder {
    width: 120px;
    height: 120px;
    margin: 0 auto 1.5rem;
    border-radius: 50%;
    overflow: hidden;
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.team-image-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.team-name {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

.team-role {
    font-size: 1rem;
    font-weight: 500;
    color: var(--color-accent);
    margin-bottom: 0.75rem;
}

.team-affiliation {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.team-links {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.team-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    background: var(--bg-secondary);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.team-link:hover {
    background: var(--color-accent);
    color: white;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background: var(--color-primary);
    color: white;
    padding: 2rem 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.footer-subtitle {
    font-size: 0.875rem;
    opacity: 0.8;
    margin-top: 0.25rem;
}

.footer-right {
    display: flex;
    gap: 1.5rem;
}

.footer-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: white;
    text-decoration: none;
    opacity: 0.9;
    transition: opacity var(--transition-fast);
}

.footer-link:hover {
    opacity: 1;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 768px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.15rem;
    }
    
    .hero-abstract {
        font-size: 1rem;
        padding: 1.25rem;
    }
    
    .hero-downloads {
        flex-direction: column;
    }
    
    .hero-download-btn {
        width: 100%;
        justify-content: center;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .nav-links {
        gap: 1rem;
        font-size: 0.875rem;
    }
    
    .nav-links a span {
        display: none;
    }
    
    .team-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-meta {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-right {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 6rem 0 3rem;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .card-downloads {
        font-size: 0.875rem;
    }
}

/* ============================================
   UTILITIES
   ============================================ */

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

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

/* ============================================
   VIDEO MODAL
   ============================================ */

.video-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    animation: fadeIn 0.3s ease;
}

.video-modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-modal-content {
    position: relative;
    width: 90%;
    max-width: 900px;
    margin: 2rem;
}

.video-modal-close {
    position: absolute;
    top: 0;
    right: 0;
    color: #000000;
    background: rgba(255, 255, 255, 0.95);
    font-size: 1.75rem;
    font-weight: bold;
    cursor: pointer;
    border: none;
    border-radius: 0 var(--border-radius) 0 8px;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition-fast), color var(--transition-fast);
    z-index: 2001;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.video-modal-close:hover,
.video-modal-close:focus {
    background: var(--color-orange);
    color: white;
}

.video-modal video {
    width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    display: block;
}

.video-modal-controls {
    display: flex;
    justify-content: flex-end;
    margin-top: 1rem;
    gap: 0.75rem;
}

.video-download-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1rem;
    background: var(--color-accent);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.875rem;
    transition: background var(--transition-fast), transform var(--transition-fast);
    border: none;
    cursor: pointer;
}

.video-download-btn:hover {
    background: var(--color-primary);
    transform: translateX(2px);
}

.video-download-btn img {
    width: 14px;
    height: 14px;
    filter: brightness(0) invert(1);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@media (max-width: 768px) {
    .video-modal-content {
        width: 95%;
        margin: 1rem;
    }
    
    .video-modal-close {
        width: 40px;
        height: 40px;
        font-size: 1.5rem;
    }
    
    .video-download-btn {
        padding: 0.5rem 0.875rem;
        font-size: 0.8125rem;
    }
}