/* ============================================
   Academic Website – Meisam Razaviyayn
   Clean, minimal design
   ============================================ */

/* --- Custom Properties --- */
:root {
    --primary: #1a365d;
    --primary-light: #2b6cb0;
    --accent: #9b2335;
    --accent-light: #c53030;
    --bg-white: #ffffff;
    --bg-light: #f7fafc;
    --bg-dark: #1a202c;
    --text-dark: #1a202c;
    --text-medium: #4a5568;
    --text-light: #718096;
    --border: #e2e8f0;
    --border-light: #edf2f7;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.10);
    --radius: 8px;
    --radius-lg: 12px;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-serif: 'Lora', 'Georgia', serif;
    --transition: 0.2s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-dark);
    background: var(--bg-white);
    -webkit-font-smoothing: antialiased;
}

a { color: var(--primary-light); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent); }

h1, h2, h3, h4 { font-family: var(--font-serif); font-weight: 600; line-height: 1.3; }
h2 { font-size: 1.8rem; color: var(--primary); margin-bottom: 0.5em; }
h3 { font-size: 1.25rem; color: var(--text-dark); }

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

/* --- Layout --- */
.container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- Navigation --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid transparent;
    transition: border-color var(--transition), box-shadow var(--transition);
}

.navbar.scrolled {
    border-bottom-color: var(--border);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-logo {
    font-family: var(--font-serif);
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--primary);
    white-space: nowrap;
}
.nav-logo:hover { color: var(--primary); }

.nav-links {
    display: flex;
    list-style: none;
    gap: 8px;
}

.nav-links a {
    display: block;
    padding: 8px 14px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-medium);
    border-radius: 6px;
    transition: color var(--transition), background var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
    background: var(--bg-light);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* --- Hero --- */
.hero {
    padding: 120px 0 60px;
    background: var(--bg-light);
}

.hero-grid {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 48px;
    align-items: start;
}

.hero-photo-wrap {
    position: relative;
}

.hero-photo {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--bg-white);
    box-shadow: var(--shadow-md);
}


.hero-info h1 {
    font-size: 2.4rem;
    color: var(--primary);
    margin-bottom: 8px;
}

.title-line {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.dept-line {
    font-size: 0.95rem;
    color: var(--text-medium);
    margin-bottom: 4px;
}

.affiliation-line {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 8px;
}

.role-line {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.6;
}

.role-line a { color: var(--text-medium); text-decoration: underline; text-decoration-color: var(--border); text-underline-offset: 2px; }
.role-line a:hover { color: var(--primary-light); }

.hero-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    font-size: 0.875rem;
    font-weight: 500;
    font-family: var(--font-sans);
    border-radius: 6px;
    transition: all var(--transition);
    white-space: nowrap;
}

.btn svg { flex-shrink: 0; }

.btn-primary {
    background: var(--primary);
    color: white;
    border: 1px solid var(--primary);
}
.btn-primary:hover { background: var(--primary-light); border-color: var(--primary-light); color: white; }

.btn-outline {
    background: var(--bg-white);
    color: var(--text-dark);
    border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--primary-light); color: var(--primary-light); }

/* --- Bio Section --- */
.bio-section {
    padding: 48px 0;
    border-bottom: 1px solid var(--border-light);
}

.bio-section p {
    max-width: 800px;
    color: var(--text-medium);
    font-size: 1.02rem;
    margin-bottom: 12px;
}

.bio-section p:last-child { margin-bottom: 0; }


/* --- Section Styles --- */
.section-intro {
    color: var(--text-medium);
    max-width: 700px;
    margin-bottom: 32px;
    font-size: 1.02rem;
}

/* --- Publications Section --- */
.publications-section {
    padding: 72px 0;
    background: var(--bg-light);
}

.publications-list { min-height: 200px; }

.year-group { margin-bottom: 32px; }

.year-header {
    font-family: var(--font-serif);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary);
    padding-bottom: 8px;
    margin-bottom: 12px;
    border-bottom: 2px solid var(--primary);
    display: inline-block;
}

.publication-item {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 16px;
    padding: 14px 0;
    border-bottom: 1px solid var(--border-light);
}

.publication-item:last-child { border-bottom: none; }

.pub-main { flex: 1; min-width: 0; }

.pub-title {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-dark);
    line-height: 1.4;
    display: inline;
}

.pub-title:hover { color: var(--primary-light); }

.pub-authors {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-top: 4px;
    line-height: 1.5;
}

.pub-authors strong { color: var(--text-dark); font-weight: 600; }

.pub-venue {
    font-size: 0.85rem;
    color: var(--accent);
    font-style: italic;
    margin-top: 2px;
}

.pub-loading {
    text-align: center;
    padding: 48px 0;
    color: var(--text-light);
}

.spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--border);
    border-top-color: var(--primary-light);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 12px;
}

@keyframes spin { to { transform: rotate(360deg); } }

.pub-error {
    text-align: center;
    padding: 48px 0;
    color: var(--text-medium);
}

.pub-error p { margin-bottom: 16px; }

.pub-footer {
    text-align: center;
    margin-top: 32px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

/* --- Teaching Section --- */
.teaching-section {
    padding: 72px 0;
    background: var(--bg-white);
}

.teaching-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.teaching-card {
    background: var(--bg-light);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: box-shadow var(--transition);
}

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

.course-code {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent);
    background: rgba(155,35,53,0.08);
    padding: 3px 10px;
    border-radius: 4px;
    margin-bottom: 10px;
}

.teaching-card h3 {
    font-size: 1.05rem;
    margin-bottom: 8px;
    color: var(--primary);
}

.teaching-card p {
    font-size: 0.9rem;
    color: var(--text-medium);
    line-height: 1.6;
}

.course-link {
    display: inline-block;
    margin-top: 10px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-light);
}

.course-link:hover { color: var(--accent); }

/* --- Group Section --- */
.group-section {
    padding: 72px 0;
    background: var(--bg-light);
}

.group-heading {
    font-size: 1.15rem;
    color: var(--text-dark);
    margin: 32px 0 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

.group-heading:first-of-type { margin-top: 0; }

.group-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.member-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 28px 20px 24px;
    transition: box-shadow var(--transition);
}

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

.member-photo {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 16px;
    border: 3px solid var(--border-light);
    box-shadow: var(--shadow-sm);
}

.member-info h4 {
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.member-info h4 a { color: var(--text-dark); }
.member-info h4 a:hover { color: var(--primary-light); }

.member-dept {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 4px;
}

.member-edu {
    font-size: 0.83rem;
    color: var(--text-light);
    margin-bottom: 6px;
}

.member-topic {
    font-size: 0.85rem;
    color: var(--text-medium);
    font-style: italic;
    line-height: 1.5;
}

.alumni-list {
    max-width: 700px;
}

.alumni-item {
    padding: 10px 0;
    font-size: 0.92rem;
    color: var(--text-medium);
    border-bottom: 1px solid var(--border-light);
}

.alumni-item:last-child { border-bottom: none; }

.alumni-years {
    color: var(--text-light);
    font-size: 0.85rem;
}

.alumni-arrow {
    color: var(--text-light);
    margin: 0 4px;
}

/* --- Footer --- */
.site-footer {
    background: var(--bg-dark);
    color: #cbd5e0;
    padding: 48px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 40px;
}

.footer-info h3 {
    font-size: 1.2rem;
    color: white;
    margin-bottom: 8px;
}

.footer-info p {
    font-size: 0.9rem;
    line-height: 1.6;
}

.footer-email { margin-top: 12px; }
.footer-email a { color: #90cdf4; }
.footer-email a:hover { color: white; }

.footer-links h4 {
    font-family: var(--font-sans);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #a0aec0;
    margin-bottom: 12px;
}

.footer-links ul { list-style: none; }

.footer-links li { margin-bottom: 8px; }

.footer-links a {
    font-size: 0.9rem;
    color: #cbd5e0;
    transition: color var(--transition);
}

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

.footer-bottom {
    margin-top: 40px;
    padding: 16px 0;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.footer-bottom p {
    font-size: 0.8rem;
    color: #718096;
    text-align: center;
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav-toggle { display: flex; }

    .nav-links {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--bg-white);
        border-bottom: 1px solid var(--border);
        flex-direction: column;
        padding: 8px 16px;
        box-shadow: var(--shadow-md);
    }

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

    .hero { padding: 100px 0 48px; }

    .hero-grid {
        grid-template-columns: 1fr;
        gap: 24px;
        text-align: center;
    }

    .hero-photo-wrap { display: flex; justify-content: center; }

    .hero-photo { width: 160px; height: 160px; }

    .hero-info h1 { font-size: 1.8rem; }

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

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

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

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    h2 { font-size: 1.5rem; }
}

@media (max-width: 480px) {
    .hero-info h1 { font-size: 1.5rem; }
    .hero-buttons { flex-direction: column; align-items: center; }
    .btn { width: 100%; justify-content: center; }
    .group-grid { grid-template-columns: 1fr; }
}