:root,
[data-theme="light"] {
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 5rem);

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  --color-bg: #f7f6f2;
  --color-surface: #fbfaf7;
  --color-surface-2: #f1eee8;
  --color-border: rgba(40, 37, 29, 0.12);
  --color-divider: rgba(40, 37, 29, 0.08);
  --color-text: #22201a;
  --color-text-muted: #6e6a62;
  --color-text-faint: #a19b91;
  --color-text-inverse: #f9f8f4;
  --color-primary: #0d6b6f;
  --color-primary-hover: #0b575a;
  --color-primary-soft: rgba(13, 107, 111, 0.1);
  --color-accent: #ad7a18;

  --shadow-sm: 0 1px 3px rgba(31, 26, 18, 0.06);
  --shadow-md: 0 10px 30px rgba(31, 26, 18, 0.08);
  --shadow-lg: 0 18px 50px rgba(31, 26, 18, 0.12);

  --radius-sm: 0.5rem;
  --radius-md: 0.875rem;
  --radius-lg: 1.25rem;
  --radius-xl: 1.75rem;
  --radius-full: 999px;

  --font-display: "Playfair Display", Georgia, serif;
  --font-body: "Inter", Arial, sans-serif;

  --content: 1180px;
  --transition: 180ms cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="dark"] {
  --color-bg: #131312;
  --color-surface: #1a1a18;
  --color-surface-2: #22221f;
  --color-border: rgba(240, 237, 230, 0.1);
  --color-divider: rgba(240, 237, 230, 0.08);
  --color-text: #f1eee7;
  --color-text-muted: #b8b2a8;
  --color-text-faint: #8b877f;
  --color-text-inverse: #171613;
  --color-primary: #69aeb1;
  --color-primary-hover: #8fc3c5;
  --color-primary-soft: rgba(105, 174, 177, 0.12);
  --color-accent: #d7a344;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 18px 50px rgba(0, 0, 0, 0.35);
}

/* base */

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top left, rgba(13, 107, 111, 0.12), transparent 28%),
    radial-gradient(circle at bottom right, rgba(173, 122, 24, 0.1), transparent 24%),
    var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.6;
}

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

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

button {
  font: inherit;
}

::selection {
  background: var(--color-primary-soft);
}

/* layout helpers */

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  background: var(--color-primary);
  color: white;
  padding: 0.75rem 1rem;
  border-radius: 0.5rem;
  z-index: 20;
}

.skip-link:focus {
  top: 1rem;
}

.container {
  width: min(var(--content), calc(100% - 2rem));
  margin: 0 auto;
}

/* header / nav */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--color-bg) 84%, transparent);
  border-bottom: 1px solid var(--color-divider);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 76px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.9rem;
  font-weight: 700;
}

.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--color-primary-soft), transparent),
    var(--color-surface);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.brand-mark svg {
  width: 24px;
  height: 24px;
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  gap: 1.25rem;
  align-items: center;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

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

.theme-toggle,
.menu-toggle {
  width: 44px;
  height: 44px;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  display: grid;
  place-items: center;
  cursor: pointer;
}

.menu-toggle {
  display: none;
}

/* hero */

.hero {
  padding: clamp(4rem, 8vw, 7rem) 0 clamp(3rem, 6vw, 5rem);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: clamp(2rem, 4vw, 4rem);
  align-items: end;
}

.hero-grid > div:first-child {
  margin-top: -4rem;
}

.chip {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.chip:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}
h1,
h2,
h3,
.display {
  font-family: var(--font-display);
  letter-spacing: -0.02em;
  line-height: 1.08;
  margin: 0;
}
.panel h3 {
  margin-bottom: 0.75rem;
}

.hero h1 {
  font-size: var(--text-3xl);
  max-width: 15ch;
  line-height: 1.02;
}

.hero p {
  max-width: 62ch;
  color: var(--color-text-muted);
  margin: 1.25rem 0 0;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.95rem;
  border-radius: var(--radius-full);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: 2rem;
  margin-top: 4rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  min-height: 48px;
  padding: 0.9rem 1.2rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: var(--text-sm);
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--color-surface);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  border-color: color-mix(in srgb, var(--color-primary) 35%, var(--color-border));
}

.hero-card {
  background: linear-gradient(
      180deg,
      color-mix(in srgb, var(--color-surface) 88%, white),
      var(--color-surface)
    );
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-lg);
  margin-top: -5.5rem;
}

.hero-card .label {
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-text-faint);
}

.hero-card .name {
  font-size: var(--text-xl);
  margin-top: 0.5rem;
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 1.75rem;
}

.stat {
  padding: 1rem;
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
}

.stat strong {
  display: block;
  font-size: 1.5rem;
  line-height: 1.1;
}

.stat span {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

/* sections */

.section {
  padding: clamp(2.5rem, 5vw, 4.5rem) 0;
}

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.section-head p {
  color: var(--color-text-muted);
  max-width: 55ch;
  margin: 0;
}

.section h2 {
  font-size: var(--text-2xl);
}

/* about */

.about-grid,
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: clamp(1.25rem, 3vw, 2rem);
  box-shadow: var(--shadow-sm);
}

.panel p {
  color: var(--color-text-muted);
}

/* highlights */

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

.mini-card {
  padding: 1.1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
}

.mini-card strong {
  display: block;
  margin-bottom: 0.35rem;
}

.mini-card span {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

/* TIMELINE LINE + DOTS + ACTIVE STATE */

.timeline {
  position: relative;
  display: grid;
  gap: 1.5rem;
  margin-top: 2rem;
  padding-left: 2rem;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 0.6rem;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(
    to bottom,
    rgba(111, 201, 214, 0.15),
    rgba(111, 201, 214, 0.5),
    rgba(111, 201, 214, 0.15)
  );
}


.timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 1.25rem;
  padding: 1.4rem 1.4rem 1.4rem 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  transition:
    transform 250ms ease,
    border-color 250ms ease,
    box-shadow 250ms ease,
    background 250ms ease;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -1.78rem;
  top: 1.7rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 2px solid rgba(111, 201, 214, 0.45);
  box-shadow: 0 0 0 6px rgba(111, 201, 214, 0.08);
}

.timeline-year {
  color: #76c8d6;
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.4;
}

.date-range {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  color: #76c8d6;
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.4;
}
.timeline-item h3 {
  font-size: 1.35rem;
  margin-bottom: 0.35rem;
}

.timeline-item p {
  color: var(--color-text-muted);
  margin: 0.45rem 0 0;
}

.timeline-item.is-active {
  border-color: rgba(111, 201, 214, 0.55);
  box-shadow: 0 18px 45px rgba(0, 0, 0, 0.22);
  transform: translateY(-4px);
  background: color-mix(in srgb, var(--color-primary-soft) 35%, var(--color-surface));
}

.timeline-item.is-active::before {
  background: #76c8d6;
  border-color: #76c8d6;
  box-shadow: 0 0 0 10px rgba(111, 201, 214, 0.16);
}

/* projects */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.project-card {
  position: relative;
  overflow: hidden;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.project-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 1rem 0;
}

.tag {
  padding: 0.42rem 0.7rem;
  border-radius: var(--radius-full);
  background: var(--color-surface-2);
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  border: 1px solid var(--color-border);
}

.project-links {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
}

.project-links a {
  color: var(--color-primary);
  font-weight: 600;
  font-size: var(--text-sm);
}




.skill-groups {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

/* Space between skills grid and Open source block */
.open-source-block {
  margin-top: 2.5rem;
}

/* Make chips clickable/inlined nicely */
.chip {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.chip {
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-full);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  font-size: var(--text-sm);
}

.achievement-list {
  display: grid;
  gap: 1rem;
}

.achievement {
  padding: 1rem 1.1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  transition:
    transform 0.2s ease,
    border-color 0.2s ease,
    box-shadow 0.2s ease,
    background-color 0.2s ease,
    color 0.2s ease;
}

.achievement strong {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--color-text);
}

.achievement p {
  margin: 0;
  color: var(--color-text-muted);
}

.achievement-clickable {
  display: block;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
}

.achievement-clickable:hover,
.achievement-clickable:focus-visible {
  transform: translateY(-3px);
  border-color: var(--color-primary);
  background: color-mix(in oklab, var(--color-surface) 88%, var(--color-primary) 12%);
  box-shadow:
    0 0 0 1px color-mix(in oklab, var(--color-primary) 30%, transparent),
    0 12px 30px color-mix(in oklab, var(--color-primary) 18%, transparent);
}

.achievement-clickable:hover strong,
.achievement-clickable:focus-visible strong {
  color: var(--color-primary);
}

.achievement-clickable:active {
  transform: translateY(0);
}
/* contact */

.contact-card {
  display: grid;
  gap: 1rem;
}

.contact-item {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--color-divider);
}

.contact-item:last-child {
  border-bottom: 0;
}

.contact-item span {
  color: var(--color-text-muted);
}

.contact-item a {
  color: var(--color-primary);
  font-weight: 600;
}

/* footer */

.footer {
  padding: 2rem 0 3rem;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

/* reveal animation */

[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 600ms ease, transform 600ms ease;
}

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

/* responsive */

@media (max-width: 960px) {
  .hero-grid,
  .about-grid,
  .skills-wrap,
  .contact-grid,
  .projects-grid,
  .highlights {
    grid-template-columns: 1fr;
  }

  .timeline {
    padding-left: 1.5rem;
  }

  .timeline-item {
    grid-template-columns: 1fr;
  }

  .timeline-item::before {
    left: -1.28rem;
    top: 1.5rem;
  }

  .nav-links {
    position: absolute;
    left: 1rem;
    right: 1rem;
    top: 76px;
    display: none;
    flex-direction: column;
    align-items: flex-start;
    padding: 1rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
  }

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

  .menu-toggle {
    display: grid;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(var(--content), calc(100% - 1.2rem));
  }

  .hero-card {
    padding: 1.25rem;
  }

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

  .section-head {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    width: 100%;
  }
}

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