@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=Outfit:wght@400;600;800&display=swap');

:root {
    --bg-primary: #f8f9fb;
    --bg-secondary: #ffffff;
    --text-primary: #1a1a2e;
    --text-secondary: #5a5a7a;
    --text-muted: #8a8aa0;
    --accent-purple: #6c3ce0;
    --accent-purple-light: #7c4dff;
    --accent-blue: #4361ee;
    --accent-gold: #b8860b;
    --glass-bg: rgba(255, 255, 255, 0.65);
    --glass-bg-hover: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(0, 0, 0, 0.06);
    --glass-border-hover: rgba(108, 60, 224, 0.25);
    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.06);
    --shadow-glow: 0 8px 32px rgba(108, 60, 224, 0.1);
    --radius-lg: 20px;
    --radius-md: 14px;
    --radius-sm: 8px;
    --radius-pill: 50px;
    --transition: 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --max-width: 1100px;
}

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

html { scroll-behavior: smooth; }

body {
    background: var(--bg-primary);
    color: var(--text-primary);
    font-family: 'Inter', -apple-system, sans-serif;
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, .logo { font-family: 'Outfit', sans-serif; }

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

img { max-width: 100%; display: block; }

/* ===== BACKGROUND DECORATION ===== */
.glow-bg {
    position: fixed; inset: 0; z-index: -1; pointer-events: none;
    background:
        radial-gradient(ellipse 50% 40% at 15% 10%, rgba(108, 60, 224, 0.06) 0%, transparent 70%),
        radial-gradient(ellipse 40% 35% at 85% 80%, rgba(67, 97, 238, 0.05) 0%, transparent 70%);
}

/* ===== NAVBAR ===== */
.navbar {
    position: fixed; top: 0; width: 100%; z-index: 1000;
    padding: 1rem 0;
    background: rgba(248, 249, 251, 0.75);
    backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
    transition: background var(--transition), padding var(--transition), box-shadow var(--transition);
}
.navbar.scrolled {
    background: rgba(248, 249, 251, 0.92);
    padding: 0.7rem 0;
    box-shadow: 0 2px 16px rgba(0, 0, 0, 0.05);
}

.nav-content {
    max-width: var(--max-width); margin: 0 auto; padding: 0 2rem;
    display: flex; justify-content: space-between; align-items: center;
}

.logo {
    font-size: 1.6rem; font-weight: 800; color: var(--text-primary);
    letter-spacing: -1px; text-decoration: none;
}

.nav-links { display: flex; align-items: center; gap: 1.8rem; }
.nav-links a {
    color: var(--text-secondary); font-size: 0.92rem; font-weight: 500;
    position: relative; text-decoration: none;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: -4px; left: 0;
    width: 0; height: 2px; background: var(--accent-purple);
    transition: width var(--transition);
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }

.nav-social { display: flex; gap: 0.8rem; margin-left: 1rem; }
.nav-social a {
    color: var(--text-muted); font-size: 0.85rem; transition: color var(--transition);
}
.nav-social a:hover { color: var(--accent-purple); }

.hamburger {
    display: none; flex-direction: column; gap: 5px; cursor: pointer;
    background: none; border: none; padding: 4px;
}
.hamburger span {
    width: 24px; height: 2px; background: var(--text-primary);
    transition: var(--transition);
}

/* ===== CONTAINER ===== */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 2rem; }

/* ===== HERO ===== */
.hero {
    min-height: 100vh; display: flex; align-items: center;
    padding: 8rem 0 4rem;
}
.hero-grid {
    display: flex; align-items: center; gap: 4rem; width: 100%;
}
.hero-text { flex: 1; }
.hero-photo-wrap {
    flex-shrink: 0; position: relative;
}
.hero-photo {
    width: 200px; height: 200px; border-radius: 50%;
    object-fit: cover; border: 3px solid rgba(108, 60, 224, 0.15);
    box-shadow: 0 8px 40px rgba(108, 60, 224, 0.12);
}
.hero-photo-ring {
    position: absolute; inset: -8px; border-radius: 50%;
    border: 1px solid rgba(108, 60, 224, 0.15);
    animation: ringPulse 4s ease-in-out infinite;
}
@keyframes ringPulse {
    0%, 100% { opacity: 0.3; transform: scale(1); }
    50% { opacity: 0.7; transform: scale(1.03); }
}

.hero-name {
    font-size: 3.8rem; font-weight: 800; line-height: 1.1; margin-bottom: 0.8rem;
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-purple) 60%, var(--accent-blue) 100%);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-role {
    font-size: 1.25rem; color: var(--text-secondary); font-weight: 400;
    margin-bottom: 0.5rem;
}
.hero-focus {
    font-size: 1rem; color: var(--text-muted); margin-bottom: 2rem;
    font-style: italic;
}
.hero-btns { display: flex; gap: 0.8rem; flex-wrap: wrap; }

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex; align-items: center; gap: 0.4rem;
    padding: 0.65rem 1.4rem; border-radius: var(--radius-pill);
    font-size: 0.88rem; font-weight: 600; text-decoration: none;
    transition: all var(--transition); cursor: pointer; border: none;
}
.btn-primary {
    background: var(--accent-purple); color: #fff;
    box-shadow: 0 4px 16px rgba(108, 60, 224, 0.25);
}
.btn-primary:hover {
    background: var(--accent-purple-light); color: #fff;
    transform: translateY(-2px); box-shadow: 0 6px 24px rgba(108, 60, 224, 0.35);
}
.btn-ghost {
    background: var(--bg-secondary); color: var(--text-primary);
    border: 1px solid var(--glass-border);
    box-shadow: var(--shadow-card);
}
.btn-ghost:hover {
    background: #fff; color: var(--accent-purple);
    border-color: var(--glass-border-hover); transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* ===== SECTIONS ===== */
section { padding: 5rem 0; }

.section-header {
    margin-bottom: 2.5rem;
}
.section-label {
    font-size: 0.78rem; font-weight: 600; text-transform: uppercase;
    letter-spacing: 2px; color: var(--accent-purple); margin-bottom: 0.5rem;
}
.section-title {
    font-size: 2.2rem; font-weight: 700; color: var(--text-primary);
}

/* ===== GLASS CARD ===== */
.glass-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
    box-shadow: var(--shadow-card);
    transition: all var(--transition);
}
.glass-card:hover {
    background: var(--glass-bg-hover);
    border-color: var(--glass-border-hover);
    box-shadow: var(--shadow-glow);
}

/* ===== ABOUT ===== */
.about-card {
    padding: 2rem;
}
.about-card p {
    color: var(--text-secondary); font-size: 1.02rem; margin-bottom: 0.8rem;
}
.about-card p:last-child { margin-bottom: 0; }

/* ===== FEATURED RESEARCH ===== */
.research-grid {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.5rem;
}
.research-card {
    padding: 0; overflow: hidden; display: flex; flex-direction: column;
}
.research-card:hover { transform: translateY(-6px); }
.research-img {
    width: 100%; height: 180px; object-fit: cover;
    border-bottom: 1px solid var(--glass-border);
}
.research-body { padding: 1.5rem; flex: 1; display: flex; flex-direction: column; }
.research-tags { display: flex; gap: 0.5rem; margin-bottom: 0.8rem; flex-wrap: wrap; }
.tag {
    font-size: 0.72rem; font-weight: 600; text-transform: uppercase;
    letter-spacing: 0.5px; padding: 0.25rem 0.7rem; border-radius: var(--radius-pill);
    background: rgba(108, 60, 224, 0.08); color: var(--accent-purple);
}
.tag-venue {
    background: rgba(184, 134, 11, 0.1); color: var(--accent-gold);
}
.research-title {
    font-size: 1.15rem; font-weight: 600; margin-bottom: 0.5rem; line-height: 1.4;
    color: var(--text-primary);
}
.research-tldr {
    font-size: 0.9rem; color: var(--text-secondary); flex: 1; margin-bottom: 1rem;
}
.research-links { display: flex; gap: 0.8rem; flex-wrap: wrap; }
.research-links a {
    font-size: 0.8rem; font-weight: 600; color: var(--accent-purple);
}
.research-links a:hover { color: var(--accent-purple-light); }

/* ===== TIMELINE SECTIONS ===== */
.timeline { position: relative; }
.timeline::before {
    content: ''; position: absolute; left: 0; top: 0; bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, var(--accent-purple) 0%, rgba(108, 60, 224, 0.1) 100%);
}
.timeline-item {
    padding-left: 2rem; margin-bottom: 2rem; position: relative;
}
.timeline-item::before {
    content: ''; position: absolute; left: -4px; top: 8px;
    width: 10px; height: 10px; border-radius: 50%;
    background: var(--accent-purple); border: 2px solid var(--bg-primary);
    box-shadow: 0 0 8px rgba(108, 60, 224, 0.25);
}
.timeline-date {
    font-size: 0.82rem; color: var(--accent-purple); font-weight: 500;
    margin-bottom: 0.2rem;
}
.timeline-title {
    font-size: 1.05rem; font-weight: 600; margin-bottom: 0.15rem;
    color: var(--text-primary);
}
.timeline-sub {
    font-size: 0.92rem; color: var(--text-secondary);
}
.timeline-detail {
    font-size: 0.88rem; color: var(--text-muted); margin-top: 0.3rem;
}

/* ===== AWARDS GRID ===== */
.awards-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 1rem;
}
.award-item {
    padding: 1.2rem 1.5rem;
}
.award-year {
    font-size: 0.78rem; font-weight: 600; color: var(--accent-gold);
    text-transform: uppercase; letter-spacing: 1px; margin-bottom: 0.3rem;
}
.award-title {
    font-size: 1rem; font-weight: 600; margin-bottom: 0.2rem;
    color: var(--text-primary);
}
.award-desc {
    font-size: 0.85rem; color: var(--text-secondary);
}

/* ===== PUBLICATIONS PAGE ===== */
.page-hero {
    padding: 8rem 0 2rem; text-align: center;
}
.page-title {
    font-size: 3rem; font-weight: 800; margin-bottom: 0.5rem;
    color: var(--text-primary);
}
.page-subtitle {
    font-size: 1.05rem; color: var(--text-secondary);
}
.page-subtitle a { color: var(--accent-purple); }

.filter-tabs {
    display: flex; justify-content: center; gap: 0.5rem; margin-bottom: 3rem;
    flex-wrap: wrap;
}
.filter-tab {
    padding: 0.5rem 1.2rem; border-radius: var(--radius-pill);
    font-size: 0.85rem; font-weight: 600; cursor: pointer;
    background: var(--bg-secondary); color: var(--text-secondary);
    border: 1px solid var(--glass-border); transition: all var(--transition);
    box-shadow: var(--shadow-card);
}
.filter-tab:hover, .filter-tab.active {
    background: rgba(108, 60, 224, 0.08); color: var(--accent-purple);
    border-color: var(--glass-border-hover);
}

.pub-list { display: flex; flex-direction: column; gap: 1.5rem; }

.pub-entry {
    display: flex; gap: 1.5rem; padding: 1.5rem;
    transition: all var(--transition);
}
.pub-entry:hover { transform: translateX(4px); }
.pub-entry.hidden { display: none; }

.pub-thumb {
    width: 160px; height: 110px; border-radius: var(--radius-md);
    object-fit: cover; flex-shrink: 0;
}
.pub-info { flex: 1; }
.pub-title-text {
    font-size: 1.05rem; font-weight: 600; margin-bottom: 0.3rem; line-height: 1.4;
    color: var(--text-primary);
}
.pub-authors {
    font-size: 0.88rem; color: var(--text-secondary); margin-bottom: 0.3rem;
}
.pub-authors strong { color: var(--text-primary); font-weight: 600; }
.pub-venue-text {
    font-size: 0.85rem; color: var(--accent-gold); font-style: italic;
    margin-bottom: 0.6rem;
}
.pub-links { display: flex; gap: 0.7rem; flex-wrap: wrap; }
.pub-link {
    font-size: 0.78rem; font-weight: 600; text-transform: uppercase;
    letter-spacing: 0.5px; color: var(--accent-purple);
    padding: 0.2rem 0.6rem; border-radius: var(--radius-sm);
    border: 1px solid rgba(108, 60, 224, 0.15);
    transition: all var(--transition);
}
.pub-link:hover {
    background: rgba(108, 60, 224, 0.08); color: var(--accent-purple-light);
    border-color: rgba(108, 60, 224, 0.3);
}

/* ===== FOOTER ===== */
footer {
    text-align: center; padding: 3rem 2rem;
    border-top: 1px solid var(--glass-border);
    margin-top: 3rem;
}
.footer-links { display: flex; justify-content: center; gap: 1.5rem; margin-bottom: 1rem; }
.footer-links a { color: var(--text-muted); font-size: 0.9rem; }
.footer-links a:hover { color: var(--accent-purple); }
.footer-copy { font-size: 0.82rem; color: var(--text-muted); }

/* ===== ANIMATIONS ===== */
.fade-up {
    opacity: 0; transform: translateY(30px);
    transition: opacity 0.7s ease-out, transform 0.7s ease-out;
}
.fade-up.is-visible { opacity: 1; transform: none; }

.stagger-1 { transition-delay: 0.05s; }
.stagger-2 { transition-delay: 0.1s; }
.stagger-3 { transition-delay: 0.15s; }
.stagger-4 { transition-delay: 0.2s; }
.stagger-5 { transition-delay: 0.25s; }
.stagger-6 { transition-delay: 0.3s; }
.stagger-7 { transition-delay: 0.35s; }
.stagger-8 { transition-delay: 0.4s; }

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
    .research-grid { grid-template-columns: 1fr; }
    .awards-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .hero-grid { flex-direction: column-reverse; text-align: center; gap: 2rem; }
    .hero-name { font-size: 2.8rem; }
    .hero-btns { justify-content: center; }
    .hero-photo { width: 160px; height: 160px; }

    .nav-links { display: none; }
    .nav-links.open {
        display: flex; flex-direction: column;
        position: absolute; top: 100%; left: 0; width: 100%;
        background: rgba(248, 249, 251, 0.95); padding: 1.5rem 2rem;
        border-bottom: 1px solid var(--glass-border);
        backdrop-filter: blur(20px);
    }
    .nav-social { display: none; }
    .hamburger { display: flex; }

    .pub-entry { flex-direction: column; }
    .pub-thumb { width: 100%; height: 160px; }

    .page-title { font-size: 2.2rem; }
    .section-title { font-size: 1.8rem; }
}