/* ===== Design System ===== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-card-hover: rgba(255, 255, 255, 0.06);
  --bg-glass: rgba(255, 255, 255, 0.05);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.15);

  --text-primary: #f0f0f5;
  --text-secondary: #a0a0b8;
  --text-muted: #6b6b80;

  --accent-primary: #7c3aed;
  --accent-secondary: #a78bfa;
  --accent-glow: rgba(124, 58, 237, 0.3);
  --accent-gradient: linear-gradient(135deg, #7c3aed, #2dd4bf);
  --accent-gradient-2: linear-gradient(135deg, #f472b6, #7c3aed, #2dd4bf);

  --success: #2dd4bf;
  --warning: #fbbf24;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Spacing */
  --section-padding: clamp(4rem, 8vw, 8rem);
  --container-max: 1200px;
  --card-radius: 16px;
  --radius-sm: 8px;
  --radius-xs: 6px;

  /* Transitions */
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html {
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: var(--accent-primary) var(--bg-secondary);
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-secondary); }
::-webkit-scrollbar-thumb { background: var(--accent-primary); border-radius: 3px; }

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

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

/* ===== Utilities ===== */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 clamp(1.5rem, 4vw, 3rem);
}

.section {
  padding: var(--section-padding) 0;
  position: relative;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent-secondary);
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.section-label::before {
  content: '';
  width: 24px;
  height: 1px;
  background: var(--accent-primary);
}

.section-title {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.7;
}

.gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.glass {
  background: var(--bg-glass);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* ===== Animated Background ===== */
.bg-grid {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  background-image:
    linear-gradient(rgba(124, 58, 237, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124, 58, 237, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

.bg-glow {
  position: fixed;
  z-index: -1;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.4;
  pointer-events: none;
}

.bg-glow-1 {
  top: -10%;
  right: -5%;
  width: 500px;
  height: 500px;
  background: var(--accent-primary);
  opacity: 0.15;
  animation: floatGlow 12s ease-in-out infinite;
}

.bg-glow-2 {
  bottom: 20%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: #2dd4bf;
  opacity: 0.08;
  animation: floatGlow 15s ease-in-out infinite reverse;
}

@keyframes floatGlow {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(30px, -30px) scale(1.1); }
}

/* ===== Navigation ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 1rem 0;
  transition: all var(--transition-smooth);
}

.nav.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-glass);
  padding: 0.75rem 0;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.nav-logo span { color: var(--accent-secondary); }

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: 0.25rem 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-gradient);
  transition: width var(--transition-smooth);
}

.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }

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

.nav-mobile-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition-fast);
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 5rem;
  position: relative;
}

.hero-content {
  max-width: 750px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--accent-secondary);
  margin-bottom: 1.5rem;
  animation: fadeInUp 0.8s ease both;
}

.hero-badge .pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(45, 212, 191, 0.4); }
  50% { opacity: 0.8; box-shadow: 0 0 0 8px rgba(45, 212, 191, 0); }
}

.hero-avatar {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  padding: 3px;
  background: var(--accent-gradient-2);
  margin-bottom: 1.5rem;
  animation: fadeInUp 0.8s ease 0.05s both;
  position: relative;
  box-shadow: 0 0 40px rgba(124, 58, 237, 0.3), 0 0 80px rgba(124, 58, 237, 0.1);
}

.hero-avatar-img {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--bg-primary);
}

.hero-name {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
  animation: fadeInUp 0.8s ease 0.1s both;
}

.hero-title {
  font-size: clamp(1rem, 2vw, 1.3rem);
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.6;
  animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-stats {
  display: flex;
  gap: 2.5rem;
  margin-bottom: 2rem;
  animation: fadeInUp 0.8s ease 0.3s both;
}

.hero-stat {
  display: flex;
  flex-direction: column;
}

.hero-stat-value {
  font-size: 1.75rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 500;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease 0.4s both;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.75rem;
  border-radius: 999px;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-smooth);
  border: none;
  font-family: var(--font-sans);
}

.btn-primary {
  background: var(--accent-gradient);
  color: white;
  box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow);
  color: white;
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-glass);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-2px);
  color: var(--text-primary);
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== About Section ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
  margin-top: 2.5rem;
}

.about-text {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

.about-text p + p { margin-top: 1rem; }

.about-text strong { color: var(--text-primary); font-weight: 600; }

.about-highlights {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.highlight-card {
  padding: 1.25rem;
  border-radius: var(--card-radius);
  transition: all var(--transition-smooth);
}

.highlight-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.highlight-card .icon {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

.highlight-card h4 {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.highlight-card p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ===== Projects Section ===== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.project-card {
  border-radius: var(--card-radius);
  padding: 2rem;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-gradient);
  opacity: 0;
  transition: opacity var(--transition-smooth);
}

.project-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
}

.project-card:hover::before { opacity: 1; }

.project-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

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

.project-links {
  display: flex;
  gap: 0.5rem;
}

.project-links a {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-xs);
  color: var(--text-muted);
  transition: all var(--transition-fast);
  font-size: 0.85rem;
}

.project-links a:hover {
  color: var(--accent-secondary);
  background: rgba(124, 58, 237, 0.1);
}

.project-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.project-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
  line-height: 1.6;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  background: rgba(124, 58, 237, 0.1);
  color: var(--accent-secondary);
  border: 1px solid rgba(124, 58, 237, 0.15);
}

.project-result {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--success);
  margin-bottom: 0.75rem;
  padding: 0.2rem 0.6rem;
  background: rgba(45, 212, 191, 0.08);
  border-radius: var(--radius-xs);
}

/* ===== Experience Timeline ===== */
.timeline {
  position: relative;
  margin-top: 2.5rem;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-primary), transparent);
}

.timeline-item {
  position: relative;
  padding-bottom: 2.5rem;
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2rem;
  top: 6px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent-primary);
  border: 2px solid var(--bg-primary);
  box-shadow: 0 0 0 3px var(--accent-glow);
  transform: translateX(-3px);
}

.timeline-item.current::before {
  background: var(--success);
  box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.3);
}

.timeline-header {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0.35rem;
}

.timeline-role {
  font-size: 1.05rem;
  font-weight: 700;
}

.timeline-company {
  font-size: 0.9rem;
  color: var(--accent-secondary);
  font-weight: 500;
}

.timeline-period {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.timeline-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 650px;
}

.timeline-bullets {
  margin: 0.6rem 0 0;
  padding-left: 1.1rem;
  max-width: 650px;
  list-style: none;
}

.timeline-bullets li {
  position: relative;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 0.35rem;
}

.timeline-bullets li::before {
  content: "▸";
  position: absolute;
  left: -1.1rem;
  color: var(--accent-secondary);
}

.timeline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.75rem;
}

/* ===== Community Section ===== */
.community-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  margin-top: 2.5rem;
}

.community-card {
  padding: 1.5rem;
  border-radius: var(--card-radius);
  transition: all var(--transition-smooth);
}

.community-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-3px);
}

.community-card .icon {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.community-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.community-card .role {
  font-size: 0.8rem;
  color: var(--accent-secondary);
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.community-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ===== Research & Awards ===== */
.research-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
  margin-top: 2.5rem;
}

.research-card {
  padding: 1.5rem;
  border-radius: var(--card-radius);
  transition: all var(--transition-smooth);
}

.research-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
}

.research-card .venue {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--warning);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.research-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.research-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ===== Skills ===== */
.skills-wrapper {
  margin-top: 2.5rem;
}

.skill-category {
  margin-bottom: 1.75rem;
}

.skill-category h3 {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.75rem;
}

.skill-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.skill-pill {
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.skill-pill:hover {
  border-color: var(--accent-primary);
  color: var(--accent-secondary);
  background: rgba(124, 58, 237, 0.08);
}

/* ===== Contact ===== */
.contact-content {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.contact-link:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  color: var(--text-primary);
  transform: translateY(-2px);
}

/* Not a link, so it must not offer link affordances. Selectable to copy the handle. */
.contact-link-static {
  cursor: default;
  user-select: all;
}

.contact-link-static:hover {
  background: initial;
  border-color: var(--border-glass);
  color: var(--text-secondary);
  transform: none;
}

/* ===== Footer ===== */
.footer {
  padding: 2rem 0;
  border-top: 1px solid var(--border-glass);
  text-align: center;
}

.footer p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ===== Scroll Reveal ===== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .projects-grid { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-mobile-toggle { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(10, 10, 15, 0.95);
    backdrop-filter: blur(20px);
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-glass);
    gap: 1rem;
  }

  .hero-stats { gap: 1.5rem; }
  .about-highlights { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: 1fr; }
  .research-grid { grid-template-columns: 1fr; }
  .hero-name { font-size: 2.25rem; }
}