/* ─── CSS Custom Properties ─────────────────────────────────────────────── */

:root {
  /* Light theme */
  --bg: #fafaf8;
  --bg-alt: #f3f2ef;
  --surface: #ffffff;
  --surface-hover: #f8f7f4;
  --border: #e5e3de;
  --border-subtle: #eeede9;

  --text-primary: #1a1917;
  --text-secondary: #5a5753;
  --text-muted: #9a9690;

  --accent: #1d4ed8;
  --accent-hover: #1e3fa8;
  --accent-light: #dbeafe;
  --accent-muted: #eff6ff;

  --success: #15803d;
  --success-light: #dcfce7;

  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Lora', Georgia, 'Times New Roman', serif;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,.08), 0 2px 4px rgba(0,0,0,.04);
  --shadow-lg: 0 12px 32px rgba(0,0,0,.1), 0 4px 8px rgba(0,0,0,.05);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --nav-height: 64px;
  --transition: 0.2s ease;
}

[data-theme="dark"] {
  --bg: #0f1117;
  --bg-alt: #161b27;
  --surface: #1c2333;
  --surface-hover: #232d42;
  --border: #2d3748;
  --border-subtle: #252d3d;

  --text-primary: #e8e6e1;
  --text-secondary: #9da3ae;
  --text-muted: #6b7280;

  --accent: #60a5fa;
  --accent-hover: #93c5fd;
  --accent-light: #1e3a5f;
  --accent-muted: #162032;

  --success: #4ade80;
  --success-light: #14532d;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,.4);
  --shadow-lg: 0 12px 32px rgba(0,0,0,.5);
}

/* ─── Reset & Base ───────────────────────────────────────────────────────── */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background-color 0.3s ease, color 0.3s ease;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { line-height: 1.25; font-weight: 600; }

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

ul { list-style: none; }

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

/* ─── Layout ─────────────────────────────────────────────────────────────── */

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4rem 0;
}

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

.section-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.section-title::after {
  content: '';
  display: block;
  width: 3rem;
  height: 3px;
  background: var(--accent);
  margin-top: 0.5rem;
  border-radius: 2px;
}

.section-sub {
  color: var(--text-secondary);
  margin-bottom: 2.5rem;
  margin-top: 0.75rem;
}

.subsection-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 3rem 0 1.25rem;
  color: var(--text-primary);
}

/* ─── Navigation ────────────────────────────────────────────────────────── */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.nav {
  display: flex;
  align-items: center;
  height: var(--nav-height);
  gap: 1.5rem;
}

.nav-brand {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-primary);
  white-space: nowrap;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

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

.nav-avatar {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center top;
  border: 2px solid var(--accent-light);
  flex-shrink: 0;
  transition: border-color var(--transition);
  background: var(--bg-alt);
}

.nav-brand:hover .nav-avatar {
  border-color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 0.25rem;
  flex: 1;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.375rem 0.75rem;
  border-radius: var(--radius-sm);
  transition: color var(--transition), background-color var(--transition);
}

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

.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.375rem 0.625rem;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 1rem;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  transition: border-color var(--transition), background-color var(--transition);
  flex-shrink: 0;
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
  background-color: var(--accent-muted);
}

.theme-icon { line-height: 1; }

[data-theme="light"] .moon { display: none; }
[data-theme="dark"]  .sun  { display: none; }

/* Nav social icons — hidden until scrolled past hero */
.nav-social {
  display: flex;
  align-items: center;
  gap: 0.125rem;
  opacity: 0;
  pointer-events: none;
  transform: translateY(-5px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.nav-social.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.nav-social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  transition: color var(--transition), background-color var(--transition);
}

.nav-social-link:hover {
  color: var(--accent);
  background-color: var(--accent-muted);
}

.nav-social-link svg {
  width: 15px;
  height: 15px;
  flex-shrink: 0;
}

.nav-hamburger {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.375rem 0.625rem;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 1.1rem;
}

.mobile-menu {
  display: none;
  flex-direction: column;
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border);
  background-color: var(--bg);
  gap: 0.5rem;
}

.mobile-menu a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.mobile-menu.open { display: flex; }

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-hamburger { display: block; }
}

/* ─── Hero ───────────────────────────────────────────────────────────────── */

.hero {
  padding: 4rem 0 3rem;
  background: var(--bg);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 3rem;
  align-items: start;
}

.hero-greeting {
  font-size: 0.875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.hero-name {
  font-family: var(--font-serif);
  font-size: clamp(2.5rem, 6vw, 3.75rem);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.hero-title {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  letter-spacing: 0.01em;
}

.hero-bio {
  max-width: 600px;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  font-size: 1.0625rem;
  line-height: 1.75;
}

.hero-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 1.75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.625rem 1.375rem;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 0.9rem;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  color: #fff;
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--accent);
  border: 1.5px solid var(--accent);
}

.btn-secondary:hover {
  background-color: var(--accent-muted);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.social-row {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 0.25rem 0;
  border-bottom: 1.5px solid transparent;
  transition: color var(--transition), border-color var(--transition);
}

.social-link svg { width: 1rem; height: 1rem; flex-shrink: 0; }

.social-link:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* Hero right column */
.hero-badge-col {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* Photo frame */
.hero-photo-frame {
  width: 158px;
  height: 158px;
  border-radius: 50%;
  overflow: hidden;
  border: 2.5px solid var(--border);
  box-shadow: var(--shadow-md);
  background: var(--bg-alt);
  margin: 0 auto;
  flex-shrink: 0;
}

.hero-photo-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  display: block;
}

.affiliation-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.affiliation-card.compact {
  padding: 0.875rem 1rem;
  gap: 0.625rem;
}

.aff-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
}

.aff-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-muted);
  flex-shrink: 0;
  margin-top: 0.45rem;
}

.aff-dot.active {
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

.aff-item strong {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-primary);
}

.aff-item span {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* Recent news (hero right column, below photo) */
.hero-news {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1rem 1.125rem;
  box-shadow: var(--shadow-sm);
}

.news-label {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.news-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.news-list li {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  font-size: 0.855rem;
  color: var(--text-secondary);
  line-height: 1.5;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--border-subtle);
}

.news-list li:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.news-date {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

@media (max-width: 900px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-badge-col { width: 100%; flex-direction: row; flex-wrap: wrap; align-items: flex-start; }
  .hero-photo-frame { width: 160px; aspect-ratio: 3 / 4; }
  .affiliation-card.compact { flex: 1; min-width: 200px; }
}

/* ─── About ──────────────────────────────────────────────────────────────── */

.about-grid {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 3rem;
  align-items: start;
}

.about-text .section-title {
  margin-bottom: 1.25rem;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: 1.0125rem;
  line-height: 1.8;
}

.about-text p:last-child { margin-bottom: 0; }

.interests-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.interests-box h3 {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.interests-list {
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
}

.interests-list li {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.interest-tag {
  display: inline-block;
  background: var(--accent-muted);
  color: var(--accent);
  border: 1px solid var(--accent-light);
  padding: 0.125rem 0.5rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

@media (max-width: 900px) {
  .about-grid { grid-template-columns: 1fr; }
}

/* ─── Research Cards ─────────────────────────────────────────────────────── */

.research-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.research-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}

.research-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.research-card.featured {
  border-color: var(--accent-light);
  background: linear-gradient(135deg, var(--surface) 0%, var(--accent-muted) 100%);
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.venue-badge {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
}

.venue-ongoing {
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid var(--accent-light);
}

.venue-completed {
  background: var(--success-light);
  color: var(--success);
  border: 1px solid var(--success-light);
}

.card-year {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.research-card h3 {
  font-size: 1.0125rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.375rem;
  line-height: 1.4;
}

.card-org {
  font-size: 0.825rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
  font-style: italic;
}

.research-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.result-list {
  margin-top: 0.875rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.result-list li {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  padding-left: 1rem;
  position: relative;
}

.result-list li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent);
}

@media (max-width: 768px) {
  .research-grid { grid-template-columns: 1fr; }
}

/* ─── Publications ───────────────────────────────────────────────────────── */

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.pub-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition);
  cursor: pointer;
  outline: none;
}

.pub-card:hover, .pub-card:focus {
  box-shadow: var(--shadow-md);
  border-color: var(--accent-light);
}

.pub-header {
  padding: 1.5rem;
}

.pub-meta-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}

.pub-badge {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.225rem 0.65rem;
  border-radius: 20px;
}

.pub-conference {
  background: #fef3c7;
  color: #92400e;
  border: 1px solid #fde68a;
}

.pub-workshop {
  background: #f3e8ff;
  color: #6b21a8;
  border: 1px solid #e9d5ff;
}

[data-theme="dark"] .pub-conference {
  background: #292210;
  color: #fcd34d;
  border-color: #3d330e;
}

[data-theme="dark"] .pub-workshop {
  background: #1e1030;
  color: #c084fc;
  border-color: #2d1a4a;
}

.pub-status {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.pub-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
  margin-bottom: 0.375rem;
}

.pub-authors {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.pub-venue {
  font-size: 0.825rem;
  color: var(--text-muted);
  font-style: italic;
  margin-bottom: 0.875rem;
}

/* Paper links + toggle buttons row */
.pub-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pub-links {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  flex-wrap: wrap;
}

.pub-link-btn {
  display: inline-flex;
  align-items: center;
  font-size: 0.775rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-muted);
  border: 1px solid var(--accent-light);
  border-radius: 20px;
  padding: 0.2rem 0.65rem;
  transition: all var(--transition);
  letter-spacing: 0.01em;
}

.pub-link-btn:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.pub-toggles {
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

.abstract-toggle,
.bibtex-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.3rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.abstract-toggle:hover,
.bibtex-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
  background-color: var(--accent-muted);
}

.toggle-icon {
  font-size: 0.65rem;
  transition: transform 0.2s ease;
}

.abstract-toggle[aria-expanded="true"] .toggle-icon,
.bibtex-toggle[aria-expanded="true"] .toggle-icon {
  transform: rotate(180deg);
}

.pub-abstract {
  padding: 1.25rem 1.5rem 1.5rem;
  border-top: 1px solid var(--border-subtle);
}

.pub-abstract p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.75;
}

/* BibTeX block */
.pub-bibtex {
  border-top: 1px solid var(--border-subtle);
}

.bibtex-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1.5rem 0.5rem;
}

.bibtex-header span {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

.copy-bibtex-btn {
  font-size: 0.775rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-muted);
  border: 1px solid var(--accent-light);
  border-radius: var(--radius-sm);
  padding: 0.2rem 0.65rem;
  cursor: pointer;
  transition: all var(--transition);
}

.copy-bibtex-btn:hover {
  background: var(--accent);
  color: #fff;
}

.copy-bibtex-btn.copied {
  background: var(--success-light);
  color: var(--success);
  border-color: var(--success-light);
}

.bibtex-code {
  margin: 0 1.5rem 1.25rem;
  padding: 1rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-family: 'SFMono-Regular', 'Consolas', 'Liberation Mono', monospace;
  font-size: 0.8rem;
  line-height: 1.65;
  color: var(--text-secondary);
  overflow-x: auto;
  white-space: pre;
}

/* ─── Timeline ───────────────────────────────────────────────────────────── */

.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border);
  border-radius: 1px;
}

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

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

.timeline-marker {
  position: absolute;
  left: -2rem;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--surface);
  border: 2.5px solid var(--accent);
  z-index: 1;
  margin-left: 1px;
}

.timeline-content {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.375rem 1.5rem;
  box-shadow: var(--shadow-sm);
}

.tl-meta {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  margin-bottom: 0.5rem;
  flex-wrap: wrap;
}

.tl-type {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.15rem 0.55rem;
  border-radius: 20px;
}

.tl-type.industry {
  background: #fff7ed;
  color: #c2410c;
  border: 1px solid #fed7aa;
}

.tl-type.research {
  background: var(--accent-muted);
  color: var(--accent);
  border: 1px solid var(--accent-light);
}

[data-theme="dark"] .tl-type.industry {
  background: #2a1200;
  color: #fb923c;
  border-color: #4a2000;
}

.tl-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.timeline-content h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.tl-org {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.875rem;
  font-style: italic;
}

.timeline-content ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.timeline-content li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding-left: 1.125rem;
  position: relative;
  line-height: 1.65;
}

.timeline-content li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

/* ─── Education ──────────────────────────────────────────────────────────── */

.edu-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.edu-logo {
  flex-shrink: 0;
  width: 160px;
  display: flex;
  align-items: center;
}

.edu-logo img {
  width: 100%;
  height: auto;
  display: block;
  filter: none;
  transition: filter var(--transition);
}

[data-theme="dark"] .edu-logo img {
  filter: brightness(0) invert(1);
}

.edu-details h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.edu-org {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 0.25rem;
}

.edu-meta {
  font-size: 0.825rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.edu-note {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* ─── Skills ─────────────────────────────────────────────────────────────── */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.skill-group {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.375rem;
  box-shadow: var(--shadow-sm);
}

.skill-group h3 {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.875rem;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.skill-tags span {
  background: var(--bg-alt);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  padding: 0.25rem 0.6rem;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition);
}

.skill-tags span:hover {
  background: var(--accent-muted);
  color: var(--accent);
  border-color: var(--accent-light);
}

@media (max-width: 900px) {
  .skills-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 560px) {
  .skills-grid { grid-template-columns: 1fr; }
}

/* ─── Achievements ───────────────────────────────────────────────────────── */

.ach-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
  margin-bottom: 0.5rem;
}

.ach-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}

.ach-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.ach-card.highlight {
  border-color: var(--accent-light);
  background: linear-gradient(135deg, var(--surface) 0%, var(--accent-muted) 100%);
}

.ach-icon {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
  line-height: 1;
}

.ach-card h3 {
  font-size: 0.975rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.ach-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

@media (max-width: 640px) {
  .ach-grid { grid-template-columns: 1fr; }
}

/* ─── Conference List ────────────────────────────────────────────────────── */

.conf-list {
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
}

.conf-item {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  box-shadow: var(--shadow-sm);
}

.conf-year {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent);
  flex-shrink: 0;
  padding-top: 0.125rem;
  min-width: 2.5rem;
}

.conf-item div {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.conf-item strong {
  color: var(--text-primary);
}

/* ─── Contact ────────────────────────────────────────────────────────────── */

.contact-inner {
  max-width: 700px;
  text-align: center;
}

.contact-inner .section-title::after {
  margin: 0.5rem auto 0;
}

.contact-sub {
  color: var(--text-secondary);
  margin: 0.75rem 0 2.5rem;
  font-size: 1.0125rem;
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.125rem 1.25rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

.contact-card:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-muted);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.contact-icon {
  font-size: 1.1rem;
  flex-shrink: 0;
  font-style: normal;
  font-weight: 700;
  color: var(--accent);
}

@media (max-width: 560px) {
  .contact-grid { grid-template-columns: 1fr; }
}

/* ─── Footer ─────────────────────────────────────────────────────────────── */

.site-footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer-inner p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.visit-counter {
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

#visitCount {
  font-weight: 600;
  color: var(--text-secondary);
}

/* ─── Responsive Misc ────────────────────────────────────────────────────── */

@media (max-width: 768px) {
  .section { padding: 3.5rem 0; }
  .section-title { font-size: 1.625rem; }
  .hero { padding: 3.5rem 0 2.5rem; }
  .edu-card { flex-direction: column; }
}

/* ─── Scroll animations (subtle) ────────────────────────────────────────── */

.fade-in {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}