/* ---------- Design tokens ---------- */
:root {
  --bg: #f7faf9;
  --surface: #edf5f2;
  --card: #ffffff;
  --text: #142421;
  --muted: #5e706c;
  --primary: #0b6b66;
  --primary-strong: #07524e;
  --accent: #d7a64a;
  --line: #d5e2de;
  --shadow: 0 22px 60px rgba(19, 55, 49, 0.11);
  --radius: 24px;
  --max-width: 1180px;
}

html[data-theme="dark"] {
  --bg: #07110f;
  --surface: #0c1a17;
  --card: #11231f;
  --text: #eaf4f1;
  --muted: #a4b8b2;
  --primary: #4fc3b5;
  --primary-strong: #85ded3;
  --accent: #f1c86d;
  --line: #26413b;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.32);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 90px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

body.menu-open {
  overflow: hidden;
}

a {
  color: inherit;
}

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  font: inherit;
}

::selection {
  background: color-mix(in srgb, var(--primary) 28%, transparent);
}

.container {
  width: min(calc(100% - 40px), var(--max-width));
  margin-inline: auto;
}

.section {
  padding: 110px 0;
}

.surface {
  background: var(--surface);
}

.skip-link {
  position: fixed;
  top: -80px;
  left: 16px;
  z-index: 999;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--text);
  color: var(--bg);
  text-decoration: none;
}

.skip-link:focus {
  top: 16px;
}

/* ---------- Navigation ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid color-mix(in srgb, var(--line) 75%, transparent);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(18px);
}

.navbar {
  min-height: 76px;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  margin-right: auto;
  text-decoration: none;
}

.brand-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: var(--primary);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  box-shadow: 0 10px 26px color-mix(in srgb, var(--primary) 22%, transparent);
}

.brand-text {
  display: grid;
  line-height: 1.1;
}

.brand-text strong {
  font-size: 0.95rem;
}

.brand-text small {
  margin-top: 4px;
  color: var(--muted);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  position: relative;
  color: var(--muted);
  font-size: 0.91rem;
  font-weight: 650;
  text-decoration: none;
  transition: color 180ms ease;
}

.nav-links a::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: -8px;
  left: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--primary);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 180ms ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
}

.theme-toggle,
.menu-toggle {
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--text);
  cursor: pointer;
}

.theme-toggle {
  width: 42px;
  height: 42px;
  display: grid;
  flex: 0 0 auto;
  place-items: center;
  border-radius: 50%;
}

.theme-icon {
  font-size: 1.15rem;
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 42px;
  padding: 9px;
  border-radius: 12px;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  margin: 5px 0;
  border-radius: 4px;
  background: currentColor;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: clip;
  padding-top: 92px;
  background:
    radial-gradient(circle at 12% 8%, color-mix(in srgb, var(--primary) 12%, transparent), transparent 30rem),
    radial-gradient(circle at 92% 42%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 26rem);
}

.hero-grid {
  min-height: 660px;
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  align-items: center;
  gap: 74px;
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--primary);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(3.4rem, 7vw, 6.6rem);
  line-height: 0.93;
  letter-spacing: -0.07em;
}

.hero h1 span {
  color: var(--primary);
}

.hero-role {
  max-width: 760px;
  margin: 28px 0 16px;
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  font-weight: 720;
  line-height: 1.4;
}

.hero-summary {
  max-width: 680px;
  margin: 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  border: 1px solid transparent;
  border-radius: 14px;
  font-weight: 760;
  text-decoration: none;
  cursor: pointer;
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button.primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 14px 32px color-mix(in srgb, var(--primary) 24%, transparent);
}

.button.primary:hover {
  background: var(--primary-strong);
}

.button.secondary {
  border-color: var(--line);
  background: var(--card);
  color: var(--text);
}

.button.compact {
  min-height: 42px;
  padding: 9px 15px;
  font-size: 0.9rem;
}

.social-row {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
  margin-top: 30px;
}

.social-row a,
.text-link {
  color: var(--primary);
  font-weight: 760;
  text-decoration: none;
}

.social-row a:hover,
.text-link:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.continuum-card {
  position: relative;
  min-height: 560px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 34px;
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--card) 96%, var(--primary) 4%), var(--card));
  box-shadow: var(--shadow);
}

.continuum-card::before {
  content: "";
  position: absolute;
  width: 300px;
  height: 300px;
  top: -130px;
  right: -100px;
  border-radius: 50%;
  background: color-mix(in srgb, var(--primary) 14%, transparent);
  filter: blur(2px);
}

.avatar-shell {
  position: absolute;
  top: 38px;
  left: 38px;
  width: 118px;
  aspect-ratio: 1;
  overflow: hidden;
  border: 8px solid var(--card);
  border-radius: 30px;
  box-shadow: 0 16px 38px rgba(18, 70, 62, 0.16);
  transform: rotate(-4deg);
}

.status-pill {
  position: absolute;
  top: 48px;
  right: 38px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: color-mix(in srgb, var(--card) 90%, transparent);
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}

.status-pill span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #2bb673;
  box-shadow: 0 0 0 5px rgba(43, 182, 115, 0.12);
}

.network-map {
  position: absolute;
  inset: 182px 28px 96px;
}

.network-map::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 28px;
  background-image:
    linear-gradient(to right, color-mix(in srgb, var(--line) 58%, transparent) 1px, transparent 1px),
    linear-gradient(to bottom, color-mix(in srgb, var(--line) 58%, transparent) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: linear-gradient(to bottom, black, transparent 92%);
}

.node {
  position: absolute;
  z-index: 2;
  width: 112px;
  min-height: 86px;
  display: grid;
  align-content: center;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--card);
  box-shadow: 0 14px 34px rgba(17, 51, 45, 0.11);
}

.node small {
  color: var(--primary);
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.node strong {
  margin-top: 5px;
  font-size: 0.91rem;
}

.cloud-node { top: 5%; left: 8%; }
.edge-node { top: 37%; right: 7%; }
.iot-node { bottom: 3%; left: 12%; }
.ai-node {
  top: 32%;
  left: 36%;
  border-color: color-mix(in srgb, var(--accent) 66%, var(--line));
  transform: scale(1.08);
}

.network-line {
  position: absolute;
  z-index: 1;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), color-mix(in srgb, var(--accent) 75%, var(--primary)));
  transform-origin: left;
}

.line-one { width: 230px; top: 92px; left: 105px; transform: rotate(28deg); }
.line-two { width: 230px; top: 190px; left: 114px; transform: rotate(-30deg); }
.line-three { width: 190px; top: 188px; left: 222px; transform: rotate(28deg); }

.visual-caption {
  position: absolute;
  right: 32px;
  bottom: 28px;
  left: 32px;
  display: grid;
  gap: 4px;
}

.visual-caption span {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.visual-caption strong {
  max-width: 420px;
  line-height: 1.35;
}

/* ---------- Facts ---------- */
.quick-facts {
  border-block: 1px solid var(--line);
  background: var(--card);
}

.facts-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.facts-grid article {
  display: grid;
  gap: 3px;
  padding: 30px;
  border-right: 1px solid var(--line);
}

.facts-grid article:last-child {
  border-right: 0;
}

.facts-grid strong {
  color: var(--primary);
  font-size: 1.25rem;
}

.facts-grid span {
  color: var(--muted);
  font-size: 0.88rem;
}

/* ---------- Section structure ---------- */
.two-column {
  display: grid;
  grid-template-columns: 0.82fr 1.18fr;
  gap: 90px;
  align-items: start;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 48px;
}

.section-heading.centered {
  margin-inline: auto;
  text-align: center;
}

.section-heading.centered > p:last-child {
  max-width: 660px;
  margin-inline: auto;
  color: var(--muted);
}

.section-heading h2 {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 4rem);
  line-height: 1.04;
  letter-spacing: -0.05em;
}

.split-heading {
  max-width: none;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
}

.about-copy {
  color: var(--muted);
  font-size: 1.06rem;
}

.about-copy p:first-child {
  margin-top: 0;
}

.about-copy p {
  margin-bottom: 20px;
}

/* ---------- Cards ---------- */
.card-grid {
  display: grid;
  gap: 18px;
}

.research-grid {
  grid-template-columns: repeat(3, 1fr);
}

.info-card {
  min-height: 240px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.info-card:hover {
  transform: translateY(-5px);
  border-color: color-mix(in srgb, var(--primary) 48%, var(--line));
  box-shadow: var(--shadow);
}

.card-number {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: color-mix(in srgb, var(--primary) 12%, transparent);
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 850;
}

.info-card h3 {
  margin: 28px 0 10px;
  line-height: 1.25;
}

.info-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

/* ---------- Publications ---------- */
.publication-list {
  border-top: 1px solid var(--line);
}

.publication {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 32px;
  padding: 38px 0;
  border-bottom: 1px solid var(--line);
}

.publication-year {
  color: var(--primary);
  font-size: 1.12rem;
  font-weight: 850;
}

.publication-body h3 {
  max-width: 890px;
  margin: 14px 0 12px;
  font-size: clamp(1.35rem, 2.8vw, 2rem);
  line-height: 1.24;
  letter-spacing: -0.025em;
}

.publication-body p {
  max-width: 900px;
  margin: 0 0 16px;
  color: var(--muted);
}

.publication-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag,
.chip-row span {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 5px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 750;
}

.tag.accent {
  border-color: color-mix(in srgb, var(--primary) 46%, var(--line));
  color: var(--primary);
}

.tag.award {
  border-color: color-mix(in srgb, var(--accent) 65%, var(--line));
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  color: color-mix(in srgb, var(--accent) 68%, var(--text));
}

/* ---------- Projects ---------- */
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.project-card {
  min-height: 300px;
  display: flex;
  flex-direction: column;
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

.project-card.featured {
  grid-column: 1 / -1;
  min-height: 360px;
  padding: 38px;
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--primary) 11%, var(--card)), var(--card) 64%);
}

.project-topline {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  color: var(--primary);
  font-size: 0.77rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.project-card h3 {
  margin: 26px 0 10px;
  font-size: 1.6rem;
  line-height: 1.18;
}

.project-card.featured h3 {
  max-width: 760px;
  font-size: clamp(2rem, 4vw, 3.2rem);
}

.project-card p {
  max-width: 800px;
  margin: 0 0 24px;
  color: var(--muted);
}

.project-card .text-link {
  margin-top: auto;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.chip-row.large {
  margin: 0;
}

/* ---------- Timeline ---------- */
.timeline {
  position: relative;
}

.timeline::before {
  content: "";
  position: absolute;
  top: 9px;
  bottom: 9px;
  left: 180px;
  width: 1px;
  background: var(--line);
}

.timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 58px;
  padding: 0 0 54px;
}

.timeline-item::before {
  content: "";
  position: absolute;
  top: 7px;
  left: 174px;
  width: 13px;
  height: 13px;
  border: 4px solid var(--bg);
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 0 1px var(--primary);
}

.timeline-date {
  color: var(--primary);
  font-size: 0.82rem;
  font-weight: 800;
}

.timeline-content h3 {
  margin: 0;
  font-size: 1.42rem;
}

.organisation {
  margin: 4px 0 12px;
  color: var(--text) !important;
  font-weight: 680;
}

.timeline-content p:last-child {
  max-width: 800px;
  margin: 0;
  color: var(--muted);
}

/* ---------- Education and skills ---------- */
.education-grid {
  display: grid;
  grid-template-columns: 0.75fr 1.25fr;
  gap: 88px;
}

.education-list {
  display: grid;
  gap: 14px;
}

.education-card {
  padding: 24px 26px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--card);
}

.education-card span {
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
}

.education-card h3 {
  margin: 10px 0 3px;
  line-height: 1.25;
}

.education-card p {
  margin: 0 0 8px;
  color: var(--muted);
}

.education-card small {
  color: var(--muted);
}

.skills-layout {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.skill-group {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--card);
}

.skill-group h3 {
  margin: 0 0 18px;
}

/* ---------- Contact ---------- */
.contact-section {
  padding-top: 30px;
}

.contact-card {
  display: grid;
  grid-template-columns: 1.4fr 0.6fr;
  align-items: end;
  gap: 60px;
  padding: 60px;
  border-radius: 32px;
  background: var(--text);
  color: var(--bg);
  box-shadow: var(--shadow);
}

.contact-card .eyebrow {
  color: var(--accent);
}

.contact-card h2 {
  max-width: 800px;
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.4rem);
  line-height: 1.08;
  letter-spacing: -0.045em;
}

.contact-card p {
  max-width: 750px;
  margin: 20px 0 0;
  color: color-mix(in srgb, var(--bg) 72%, transparent);
}

.contact-actions {
  display: grid;
  gap: 10px;
}

.contact-card .button.secondary {
  border-color: color-mix(in srgb, var(--bg) 22%, transparent);
  background: transparent;
  color: var(--bg);
}

.copy-status {
  min-height: 24px;
  text-align: center;
  color: color-mix(in srgb, var(--bg) 72%, transparent);
  font-size: 0.8rem;
}

/* ---------- Footer ---------- */
.site-footer {
  padding: 54px 0 34px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: start;
  gap: 30px;
}

.footer-grid strong {
  font-size: 1.05rem;
}

.footer-grid p {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 18px;
}

.footer-links a {
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 700;
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--primary);
}

.copyright {
  grid-column: 1 / -1;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

/* ---------- Motion ---------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 600ms ease, transform 600ms ease;
}

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

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .menu-toggle {
    display: block;
  }

  .nav-links {
    position: fixed;
    inset: 77px 0 auto;
    max-height: 0;
    overflow: hidden;
    display: grid;
    gap: 0;
    border-bottom: 1px solid var(--line);
    background: var(--bg);
    transition: max-height 260ms ease;
  }

  .nav-links.open {
    max-height: 460px;
  }

  .nav-links a {
    padding: 16px 24px;
    border-bottom: 1px solid var(--line);
  }

  .nav-links a::after {
    display: none;
  }

  .hero-grid,
  .two-column,
  .education-grid,
  .contact-card {
    grid-template-columns: 1fr;
  }

  .hero-grid {
    min-height: auto;
  }

  .hero-visual {
    max-width: 620px;
    width: 100%;
    margin-inline: auto;
  }

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

  .facts-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .facts-grid article:nth-child(2) {
    border-right: 0;
  }

  .facts-grid article:nth-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }

  .two-column,
  .education-grid {
    gap: 30px;
  }

  .contact-card {
    align-items: start;
    gap: 36px;
  }

  .contact-actions {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .copy-status {
    grid-column: 1 / -1;
  }
}

@media (max-width: 700px) {
  .container {
    width: min(calc(100% - 28px), var(--max-width));
  }

  .section {
    padding: 78px 0;
  }

  .navbar {
    gap: 12px;
  }

  .brand-text {
    display: none;
  }

  .hero {
    padding-top: 62px;
  }

  .hero-grid {
    gap: 48px;
  }

  .hero h1 {
    font-size: clamp(3.15rem, 15vw, 5rem);
  }

  .hero-actions .button {
    width: 100%;
  }

  .continuum-card {
    min-height: 510px;
  }

  .status-pill {
    top: 42px;
    right: 24px;
    max-width: 190px;
  }

  .avatar-shell {
    top: 32px;
    left: 24px;
    width: 96px;
  }

  .network-map {
    inset: 170px 16px 100px;
    transform: scale(0.92);
  }

  .facts-grid,
  .research-grid,
  .project-grid,
  .skills-layout {
    grid-template-columns: 1fr;
  }

  .facts-grid article {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .facts-grid article:last-child {
    border-bottom: 0;
  }

  .project-card.featured {
    grid-column: auto;
  }

  .split-heading {
    align-items: start;
    flex-direction: column;
  }

  .publication {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 32px 0;
  }

  .timeline::before {
    left: 7px;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 0 0 44px 34px;
  }

  .timeline-item::before {
    left: 1px;
  }

  .contact-card {
    padding: 34px 24px;
  }

  .contact-actions {
    grid-template-columns: 1fr;
  }

  .copy-status {
    grid-column: auto;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .footer-links {
    justify-content: flex-start;
  }
}

@media (max-width: 430px) {
  .network-map {
    transform: scale(0.78);
    transform-origin: center;
  }

  .status-pill {
    display: none;
  }
}