:root {
  --bg: #0b0d12;
  --bg-elevated: #12151c;
  --bg-card: #161a23;
  --border: #262b38;
  --text: #eef0f5;
  --text-muted: #9aa2b1;
  --accent: #7dd3fc;
  --accent-2: #a78bfa;
  --accent-contrast: #05070a;
  --shadow: 0 20px 60px -30px rgba(0, 0, 0, 0.6);
  --radius: 16px;
  --max-width: 920px;
  --card-overlay-start: rgba(11, 13, 18, 0.55);
  --card-overlay-end: rgba(11, 13, 18, 0.92);
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f7f7fb;
  --bg-elevated: #ffffff;
  --bg-card: #ffffff;
  --border: #e4e5ee;
  --text: #14161f;
  --text-muted: #5a6072;
  --accent: #2563eb;
  --accent-2: #7c3aed;
  --accent-contrast: #ffffff;
  --shadow: 0 20px 60px -30px rgba(20, 20, 40, 0.25);
  --card-overlay-start: rgba(255, 255, 255, 0.6);
  --card-overlay-end: rgba(255, 255, 255, 0.95);
  color-scheme: light;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, "Inter", Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.3s ease, color 0.3s ease;
}

a {
  color: inherit;
}

img {
  max-width: 100%;
}

/* Header / nav */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  font-weight: 700;
  letter-spacing: 0.02em;
  text-decoration: none;
  font-size: 1rem;
  color: var(--text);
}

.nav-links {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
}

.nav-links a {
  text-decoration: none;
  font-size: 0.9rem;
  color: var(--text-muted);
  transition: color 0.2s ease;
  white-space: nowrap;
}

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

.nav-controls {
  display: flex;
  align-items: center;
  gap: 10px;
}

.icon-btn {
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  width: 36px;
  height: 36px;
  border-radius: 10px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1rem;
  transition: border-color 0.2s ease, transform 0.15s ease;
}

.icon-btn:hover {
  border-color: var(--accent);
}

.icon-btn:active {
  transform: scale(0.94);
}

.lang-btn {
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

#nav-toggle {
  display: none;
}

/* Hero */

.hero {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 96px 24px 64px;
  display: flex;
  align-items: center;
  gap: 40px;
}

.hero-avatar {
  flex-shrink: 0;
  width: 128px;
  height: 128px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-contrast);
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: var(--shadow);
}

.hero-text .eyebrow {
  display: block;
  margin-bottom: 10px;
}

.hero-text h1 {
  margin: 0 0 6px;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.15;
}

.hero-role {
  margin: 0 0 16px;
  color: var(--accent);
  font-weight: 600;
  font-size: 1.05rem;
}

.hero-tagline {
  margin: 0 0 18px;
  color: var(--text-muted);
  max-width: 56ch;
}

.hero-meta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* Section shell */

.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 24px;
  border-top: 1px solid var(--border);
}

.section-header {
  margin-bottom: 32px;
}

.eyebrow {
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--accent);
  font-weight: 700;
}

.section-header h2 {
  margin: 6px 0 0;
  font-size: 1.6rem;
}

.section-note {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin: 8px 0 0;
}

.prose p {
  color: var(--text-muted);
  margin: 0 0 14px;
  max-width: 70ch;
}

/* Timeline */

.timeline {
  position: relative;
  padding-left: 28px;
  border-left: 2px solid var(--border);
}

.timeline-item {
  position: relative;
  padding-bottom: 36px;
}

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

.timeline-dot {
  position: absolute;
  left: -34px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 20%, transparent);
}

.timeline-period {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--accent);
  text-transform: uppercase;
}

.timeline-content h3 {
  margin: 4px 0 2px;
  font-size: 1.1rem;
}

.timeline-org {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 8px;
}

.timeline-location::before {
  content: "· ";
}

.timeline-content p {
  margin: 0 0 10px;
  color: var(--text-muted);
}

.timeline--compact .timeline-item {
  padding-bottom: 24px;
}

/* Tags */

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  font-size: 0.78rem;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--text-muted);
  cursor: default;
}

.skill-tag {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.skill-level {
  color: var(--accent);
  font-size: 0.85em;
  line-height: 1;
}

/* Skills */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.skill-card h3 {
  margin: 0 0 12px;
  font-size: 1rem;
}

/* Card grid (projects/publications) */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: var(--shadow);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

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

.project-card--image {
  background-size: cover;
  background-position: center;
  background-blend-mode: normal;
}

.project-card h3 {
  margin: 0;
  font-size: 1.05rem;
}

.project-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.92rem;
}

.card-link {
  margin-top: auto;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
}

.card-link:hover {
  text-decoration: underline;
}

/* Contact */

.contact-section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 24px 80px;
  border-top: 1px solid var(--border);
  text-align: center;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  margin-top: 20px;
}

.contact-links a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  padding: 10px 18px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  font-size: 0.9rem;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.contact-links a:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.site-footer {
  text-align: center;
  padding: 24px;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* Reveal-on-scroll animation */

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Responsive */

@media (max-width: 720px) {
  .hero {
    flex-direction: column;
    text-align: center;
    padding-top: 64px;
  }

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

  #nav-toggle {
    display: inline-flex;
  }

  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 12px 24px;
    display: none;
    gap: 14px;
  }

  .nav-links.is-open {
    display: flex;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal {
    transition: none;
    opacity: 1;
    transform: none;
  }
}

/* Print: compact single-page, two-column resume layout */

@media print {
  @page {
    size: A4;
    margin: 10mm 12mm;
  }

  :root,
  :root[data-theme="light"] {
    --bg: #ffffff;
    --bg-elevated: #ffffff;
    --bg-card: #ffffff;
    --border: #cfd2db;
    --text: #101114;
    --text-muted: #444a58;
    --accent: #1d4ed8;
    --shadow: none;
  }

  html,
  body {
    background: #fff;
    font-size: 7.8pt;
    line-height: 1.28;
  }

  .site-header,
  .site-footer,
  #theme-toggle,
  #lang-toggle,
  #nav-toggle,
  .nav-links,
  .card-link,
  .section-note {
    display: none !important;
  }

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

  .reveal {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }

  /* Visually move the contact strip to the top of the printed page
     (name → contact line → two-column body) without changing the on-screen
     DOM order, which stays contact-at-the-bottom. */
  main {
    display: flex;
    flex-direction: column;
  }

  .hero {
    order: 1;
  }

  .contact-section {
    order: 2;
  }

  #main-content {
    order: 3;
  }

  /* Header row: name, title, tagline, contact — full width, compact.
     Overrides the max-width:720px mobile layout, which A4 print width
     otherwise triggers (it stacks/centers the hero and adds a big
     padding-top meant for the on-screen mobile nav). */
  .hero {
    max-width: none;
    flex-direction: row;
    text-align: left;
    padding: 0 0 6pt;
    gap: 8pt;
    align-items: center;
  }

  .hero-avatar {
    width: 26pt;
    height: 26pt;
    font-size: 9pt;
    background: none;
    color: var(--text);
    border: 1pt solid var(--text);
    box-shadow: none;
  }

  .hero-text .eyebrow {
    display: none;
  }

  .hero-text h1 {
    font-size: 13pt;
    margin: 0;
  }

  .hero-role {
    font-size: 8pt;
    margin: 0 0 2pt;
  }

  .hero-tagline {
    font-size: 7pt;
    margin: 0 0 2pt;
  }

  .hero-meta {
    font-size: 6.5pt;
    justify-content: flex-start;
  }

  /* Two-column flow for the bulk of the content */
  #main-content {
    column-count: 2;
    column-gap: 14pt;
    max-width: none;
  }

  .section {
    max-width: none;
    padding: 0 0 5pt;
    margin-bottom: 5pt;
    border-top: none;
  }

  .section-header {
    margin-bottom: 4pt;
  }

  /* Redundant with the h2 title right below it — drop it to save vertical space */
  .section-header .eyebrow {
    display: none;
  }

  .section-header h2 {
    font-size: 9.5pt;
    margin-top: 0;
    break-after: avoid-column;
  }

  .prose p {
    font-size: 7.5pt;
    margin: 0 0 4pt;
  }

  /* Timeline */
  .timeline {
    padding-left: 9pt;
    border-left: 1pt solid var(--border);
  }

  .timeline-item {
    padding-bottom: 4.5pt;
    break-inside: avoid-column;
  }

  .timeline-dot {
    left: -12.5pt;
    top: 2pt;
    width: 5pt;
    height: 5pt;
    box-shadow: none;
  }

  .timeline-period {
    font-size: 6.2pt;
  }

  .timeline-content h3 {
    font-size: 8pt;
    margin: 1pt 0 1pt;
  }

  .timeline-org {
    font-size: 7pt;
    margin-bottom: 2pt;
  }

  .timeline-content p {
    font-size: 7pt;
    margin: 0 0 2.5pt;
  }

  .timeline--compact .timeline-item {
    padding-bottom: 3pt;
  }

  /* Grids collapse to a single column within each print column */
  .skills-grid,
  .card-grid {
    display: block;
  }

  .skill-card,
  .project-card {
    border: none;
    box-shadow: none;
    padding: 0 0 4pt;
    break-inside: avoid-column;
    gap: 2pt;
    background-image: none !important;
  }

  .skill-card h3,
  .project-card h3 {
    font-size: 8pt;
    margin: 0 0 2pt;
  }

  .project-card p {
    font-size: 7pt;
  }

  .tag {
    font-size: 6pt;
    padding: 1pt 4pt;
    border-color: var(--border);
  }

  .skill-tag {
    gap: 3pt;
  }

  /* Contact strip: single compact line, moved above the two-column body
     (see the `order` rules near .hero) so it reads right under the name. */
  .contact-section {
    max-width: none;
    padding: 0 0 6pt;
    margin-bottom: 6pt;
    border-top: none;
    border-bottom: 1pt solid var(--border);
    text-align: left;
  }

  .contact-section .eyebrow,
  .contact-section h2,
  .contact-section .section-note {
    display: none;
  }

  .contact-links {
    justify-content: flex-start;
    gap: 10pt;
    margin-top: 0;
  }

  .contact-links a {
    border: none;
    padding: 0;
    font-size: 7.5pt;
    gap: 3pt;
  }

  .contact-links a svg {
    width: 8pt;
    height: 8pt;
  }
}