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

:root {
  --g1: #667eea;
  --g2: #764ba2;
  --g3: #f64f59;
  --g4: #f093fb;
  --g5: #4facfe;
  --g6: #00f2fe;

  --bg: #0d0d1a;
  --bg-alt: #13131f;
  --surface: #1a1a2e;
  --border: rgba(255,255,255,0.08);
  --text: #e8e8f0;
  --text-muted: #888899;

  --radius: 14px;
  --font: 'Inter', system-ui, sans-serif;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* ── Navbar ───────────────────────────────────────── */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  background: rgba(13,13,26,0.75);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-weight: 700;
  font-size: 1.1rem;
  background: linear-gradient(90deg, var(--g1), var(--g4));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.nav-links {
  list-style: none;
  display: flex;
  gap: 1.8rem;
}
.nav-links a {
  font-size: 0.9rem;
  color: var(--text-muted);
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }

/* ── Hero ─────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  text-align: center;
  padding: 80px 2rem 4rem;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 30%, rgba(102,126,234,0.25) 0%, transparent 60%),
    radial-gradient(ellipse 60% 50% at 80% 70%, rgba(240,147,251,0.2) 0%, transparent 60%),
    radial-gradient(ellipse 40% 40% at 50% 0%,  rgba(79,172,254,0.15) 0%, transparent 60%);
  z-index: 0;
}

.hero-content { position: relative; z-index: 1; max-width: 680px; }

.avatar-wrap {
  width: 180px;
  height: 180px;
  margin: 0 auto 1.5rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--g1), var(--g4), var(--g5));
  padding: 3px;
}
.avatar {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  object-position: center 20%;
  background: var(--surface);
  display: block;
}

.hero-name {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  margin-bottom: 0.75rem;
}
.gradient-text {
  background: linear-gradient(90deg, var(--g1), var(--g4), var(--g5), var(--g6));
  background-size: 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: shimmer 4s linear infinite;
}
@keyframes shimmer {
  0%   { background-position: 0% }
  100% { background-position: 200% }
}

.hero-tagline {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.hero-quote {
  font-size: 0.88rem;
  font-style: italic;
  color: rgba(255,255,255,0.35);
  margin-bottom: 2rem;
  letter-spacing: 0.01em;
}
.hero-quote-author {
  font-style: normal;
  color: rgba(255,255,255,0.2);
  font-size: 0.8rem;
}

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

.scroll-hint {
  position: absolute;
  bottom: 2rem;
  font-size: 1.4rem;
  color: var(--text-muted);
  animation: bounce 2s ease infinite;
}
@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(8px); }
}

/* ── Buttons ──────────────────────────────────────── */
.btn-pill {
  display: inline-block;
  padding: 0.55rem 1.5rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 600;
  background: linear-gradient(135deg, var(--g1), var(--g4));
  color: #fff;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 20px rgba(102,126,234,0.35);
}
.btn-pill:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(102,126,234,0.5);
}
.btn-pill.outline {
  background: transparent;
  border: 1.5px solid rgba(255,255,255,0.25);
  box-shadow: none;
  color: var(--text);
}
.btn-pill.outline:hover {
  border-color: var(--g1);
  color: var(--g4);
  box-shadow: none;
}

/* ── Sections ─────────────────────────────────────── */
.section { padding: 6rem 2rem; }
.alt-bg { background: var(--bg-alt); }

.container {
  max-width: 860px;
  margin: 0 auto;
}

.section-title {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 2.5rem;
  position: relative;
  display: inline-block;
}
.section-title::after {
  content: '';
  position: absolute;
  left: 0; bottom: -8px;
  width: 48px; height: 3px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--g1), var(--g4));
}

/* ── About ────────────────────────────────────────── */
.about-text {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 680px;
  line-height: 1.9;
}

/* ── Timeline ─────────────────────────────────────── */
.timeline { position: relative; padding-left: 2rem; }
.timeline::before {
  content: '';
  position: absolute;
  left: 7px; top: 0; bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--g1), var(--g4), transparent);
}

.timeline-item {
  position: relative;
  margin-bottom: 2.5rem;
}
.tl-dot {
  position: absolute;
  left: -2rem;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--g1), var(--g4));
  box-shadow: 0 0 0 3px var(--bg-alt);
}
.tl-body h3 { font-size: 1.05rem; font-weight: 600; margin-bottom: 0.25rem; }
.tl-meta { font-size: 0.82rem; color: var(--text-muted); display: block; margin-bottom: 0.5rem; }
.tl-body p  { color: var(--text-muted); font-size: 0.95rem; }

/* ── Cards (Projects) ─────────────────────────────── */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(102,126,234,0.5);
  box-shadow: 0 8px 32px rgba(102,126,234,0.15);
}
.card-title { font-size: 1rem; font-weight: 600; }
.card-desc  { font-size: 0.88rem; color: var(--text-muted); flex: 1; }
.card-tags  { display: flex; gap: 0.4rem; flex-wrap: wrap; }
.card-link  { font-size: 0.85rem; color: var(--g4); font-weight: 600; transition: color 0.2s; }
.card-link:hover { color: var(--g5); }

/* ── Tags ─────────────────────────────────────────── */
.tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
  background: rgba(102,126,234,0.15);
  color: var(--g4);
  border: 1px solid rgba(102,126,234,0.25);
}

/* ── Skills ───────────────────────────────────────── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 2rem;
}
.skill-group h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.skill-tags { display: flex; gap: 0.5rem; flex-wrap: wrap; }

/* ── Contact ──────────────────────────────────────── */
.contact-center { text-align: center; }
.contact-sub {
  color: var(--text-muted);
  margin-bottom: 2rem;
  font-size: 1rem;
}
.contact-links { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

/* ── Footer ───────────────────────────────────────── */
.footer {
  text-align: center;
  padding: 2rem;
  font-size: 0.82rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}
.footer a { color: var(--g4); }

/* ── Responsive ───────────────────────────────────── */
@media (max-width: 640px) {
  .nav-links { display: none; }
  .hero { padding-top: 80px; }
  .section { padding: 4rem 1.25rem; }
  .card-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr 1fr; }
}

/* ── Publications ─────────────────────────────────── */
.pub-list { display: flex; flex-direction: column; }

.pub-item {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border);
  transition: background 0.2s;
}
.pub-item:first-child { border-top: 1px solid var(--border); }

.pub-year {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--g4);
  min-width: 36px;
  padding-top: 3px;
  letter-spacing: 0.03em;
}

.pub-body { flex: 1; }
.pub-title {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
  line-height: 1.5;
}
.pub-authors {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
}
.pub-venue {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.15rem 0.6rem;
  border-radius: 999px;
  background: rgba(79,172,254,0.12);
  color: var(--g5);
  border: 1px solid rgba(79,172,254,0.25);
  font-weight: 600;
}

.pub-venue.oral {
  background: rgba(246,79,89,0.12);
  color: #f97b85;
  border-color: rgba(246,79,89,0.3);
}
.pub-note {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 1rem;
}