/* ========================================
   Bridge of Time - Portfolio Stylesheet
   CPT208 Group B4-3
   ======================================== */

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #2c3e50;
    --primary-light: #34495e;
    --accent: #e67e22;
    --accent-light: #f39c12;
    --warm: #e74c3c;
    --warm-light: #fff5f5;
    --bg: #fafafa;
    --bg-alt: #f0ebe3;
    --text: #2c3e50;
    --text-light: #7f8c8d;
    --white: #ffffff;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.12);
    --radius: 12px;
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
}

h1, h2, h3 {
    font-family: 'Playfair Display', Georgia, serif;
    line-height: 1.3;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- Navigation --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 40px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 1px 10px rgba(0, 0, 0, 0.06);
}

.nav-brand {
    font-family: 'Playfair Display', serif;
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 32px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
}

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

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

/* --- Hero --- */
.hero {
    position: relative;
    height: 100vh;
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(135deg, #2c3e50 0%, #4a6741 50%, #e67e22 100%);
    overflow: hidden;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="rgba(255,255,255,0.05)" d="M0,160L48,170.7C96,181,192,203,288,197.3C384,192,480,160,576,154.7C672,149,768,171,864,186.7C960,203,1056,213,1152,197.3C1248,181,1344,139,1392,117.3L1440,96L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>') no-repeat bottom;
    background-size: cover;
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: 0 24px;
}

.hero-tag {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 16px;
}

.hero-title {
    font-size: clamp(3rem, 8vw, 5.5rem);
    color: var(--white);
    margin-bottom: 16px;
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: clamp(1rem, 2.5vw, 1.3rem);
    color: rgba(255, 255, 255, 0.85);
    font-weight: 300;
    max-width: 600px;
    margin: 0 auto 32px;
}

.hero-btn {
    display: inline-block;
    padding: 14px 36px;
    background: var(--accent);
    color: var(--white);
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(230, 126, 34, 0.4);
}

.hero-btn:hover {
    background: var(--accent-light);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(230, 126, 34, 0.5);
}

/* --- Sections --- */
.section {
    padding: 100px 0;
}

.section-alt {
    background: var(--bg-alt);
}

.section-title {
    font-size: 2.4rem;
    text-align: center;
    margin-bottom: 12px;
    color: var(--primary);
}

.section-desc {
    text-align: center;
    color: var(--text-light);
    max-width: 600px;
    margin: 0 auto 48px;
}

/* --- About --- */
.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
    margin-bottom: 48px;
}

.about-card {
    background: var(--white);
    padding: 32px 24px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.about-icon {
    font-size: 2.4rem;
    margin-bottom: 12px;
}

.about-card h3 {
    margin-bottom: 8px;
    font-size: 1.1rem;
}

.about-card p {
    color: var(--text-light);
    font-size: 0.9rem;
}

.motivation-box {
    background: var(--white);
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border-left: 4px solid var(--accent);
}

.motivation-box h3 {
    font-size: 1.4rem;
    margin-bottom: 16px;
    color: var(--accent);
}

.motivation-box p {
    margin-bottom: 12px;
    color: var(--text);
}

/* --- Team --- */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 32px;
}

.team-card {
    background: var(--white);
    padding: 36px 24px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.team-avatar {
    margin-bottom: 16px;
}

.avatar-placeholder {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), var(--accent-light));
    color: var(--white);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    font-family: 'Inter', sans-serif;
}

.team-card h3 {
    font-size: 1.2rem;
    margin-bottom: 4px;
}

.team-id {
    color: var(--text-light);
    font-size: 0.85rem;
    margin-bottom: 8px;
}

.team-role {
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 500;
}

/* --- Personas --- */
.persona-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(480px, 1fr));
    gap: 32px;
}

.persona-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.persona-card:hover {
    box-shadow: var(--shadow-hover);
}

.persona-header {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 24px 28px;
}

.persona-young .persona-header {
    background: linear-gradient(135deg, #3498db, #2980b9);
    color: var(--white);
}

.persona-elder .persona-header {
    background: linear-gradient(135deg, #e67e22, #d35400);
    color: var(--white);
}

.persona-avatar {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    flex-shrink: 0;
}

.persona-header h3 {
    font-size: 1.3rem;
    font-family: 'Inter', sans-serif;
    font-weight: 600;
}

.persona-age {
    opacity: 0.85;
    font-size: 0.9rem;
}

.persona-body {
    padding: 28px;
}

.persona-section {
    margin-bottom: 20px;
}

.persona-section h4 {
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--primary);
}

.persona-section p {
    font-size: 0.9rem;
    color: var(--text);
}

.persona-tags {
    margin-bottom: 20px;
}

.persona-tag-group {
    margin-bottom: 16px;
}

.persona-tag-group h4 {
    font-family: 'Inter', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--primary);
}

.tag {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    margin: 0 4px 6px 0;
}

.tag-goal {
    background: #e8f5e9;
    color: #2e7d32;
}

.tag-pain {
    background: #fce4ec;
    color: #c62828;
}

.proficiency-bar {
    width: 100%;
    height: 8px;
    background: #ecf0f1;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 4px;
}

.proficiency-fill {
    height: 100%;
    border-radius: 4px;
    transition: width 1s ease;
}

.persona-young .proficiency-fill {
    background: linear-gradient(90deg, #3498db, #2ecc71);
}

.persona-elder .proficiency-fill {
    background: linear-gradient(90deg, #e67e22, #f39c12);
}

.proficiency-label {
    font-size: 0.8rem;
    color: var(--text-light);
}

.persona-quote {
    border-top: 1px solid #ecf0f1;
    padding-top: 16px;
}

.persona-quote blockquote {
    font-style: italic;
    color: var(--text-light);
    font-size: 0.9rem;
    padding-left: 16px;
    border-left: 3px solid var(--accent);
}

/* --- Research Placeholder --- */
.placeholder-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.placeholder-card {
    background: var(--white);
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.placeholder-card h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.placeholder-card p {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 16px;
}

.status-badge {
    display: inline-block;
    padding: 4px 14px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
    background: #fff3e0;
    color: #e65100;
}

/* --- Timeline --- */
.timeline {
    position: relative;
    max-width: 600px;
    margin: 0 auto;
    padding-left: 40px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 15px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #ddd;
}

.timeline-item {
    position: relative;
    margin-bottom: 32px;
}

.timeline-marker {
    position: absolute;
    left: -33px;
    top: 4px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: #ddd;
    border: 3px solid var(--bg);
}

.timeline-item.done .timeline-marker {
    background: #2ecc71;
}

.timeline-item.active .timeline-marker {
    background: var(--accent);
    box-shadow: 0 0 0 4px rgba(230, 126, 34, 0.2);
}

.timeline-content h3 {
    font-family: 'Inter', sans-serif;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.timeline-content p {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* --- Footer --- */
.footer {
    background: var(--primary);
    color: rgba(255, 255, 255, 0.7);
    text-align: center;
    padding: 40px 24px;
    font-size: 0.9rem;
}

.footer p {
    margin-bottom: 4px;
}

.footer strong {
    color: var(--white);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        box-shadow: var(--shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

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

    .hero-title {
        font-size: 2.5rem;
    }

    .section {
        padding: 60px 0;
    }

    .motivation-box {
        padding: 24px;
    }
}

@media (max-width: 480px) {
    .navbar {
        padding: 12px 20px;
    }

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

    .team-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
}