/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html, body, h1, h2, h3, h4, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, picture { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }

/* ---------- Design tokens ---------- */
:root {
  --bg: #0a0a0b;
  --bg-raised: #161618;
  --bg-card: #17181b;
  --border: #2a2b30;
  --border-strong: #43444c;
  --divider: #45464f;
  --text: #ededee;
  --text-muted: #aeaeb6;
  --text-faint: #82828a;
  --accent: #7c8db5;
  --accent-dim: #5c6a89;
  --accent-rgb: 124, 141, 181;
  --dot-color: rgba(237, 237, 238, 0.06);
  --header-bg: rgba(10, 10, 11, 0.7);
  --max-width: 1160px;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

[data-theme="light"] {
  --bg: #f6f6f4;
  --bg-raised: #ececea;
  --bg-card: #ffffff;
  --border: #dcdcda;
  --border-strong: #b3b3b0;
  --divider: #dcdcda;
  --text: #1a1a1c;
  --text-muted: #48484f;
  --text-faint: #67676f;
  --accent: #4f5f82;
  --accent-dim: #5f6e8b;
  --accent-rgb: 79, 95, 130;
  --dot-color: rgba(26, 26, 28, 0.05);
  --header-bg: rgba(246, 246, 244, 0.75);
}

html { scroll-behavior: smooth; }

body {
  background-color: var(--bg);
  background-image: radial-gradient(var(--dot-color) 1px, transparent 0);
  background-size: 28px 28px;
  background-position: -14px -14px;
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.25s ease, color 0.25s ease;
}

main { flex: 1; }

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
}

::selection { background: var(--accent-dim); color: #fff; }

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  transition: background-color 0.25s ease;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
}

.nav-logo {
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
}
.nav-logo:hover { color: var(--accent); }

.nav-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  border-radius: 9999px;
  border: 1px solid var(--border);
  color: var(--text);
  transition: border-color 0.18s ease, color 0.18s ease;
}
.theme-toggle:hover { border-color: var(--accent-dim); color: var(--accent); }

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

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

.nav-toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 44px;
  height: 20px;
  position: relative;
  flex-shrink: 0;
}
.nav-toggle span {
  position: absolute;
  left: 4px;
  right: 4px;
  height: 1.5px;
  background: var(--text);
  transition: transform 0.25s ease, opacity 0.2s ease, top 0.25s ease;
}
.nav-toggle span:nth-child(1) { top: 4px; }
.nav-toggle span:nth-child(2) { top: 13px; }

.nav-toggle.is-open span:nth-child(1) { top: 9px; transform: rotate(45deg); }
.nav-toggle.is-open span:nth-child(2) { top: 9px; transform: rotate(-45deg); }

/* Full-screen overlay nav */
.nav-overlay {
  position: fixed;
  inset: 0;
  z-index: 90;
  background: var(--bg);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 120px 32px 48px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s;
}

.nav-overlay.is-open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.nav-overlay-links {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
}

.nav-overlay-links a {
  font-size: clamp(2.2rem, 8vw, 4rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text-muted);
  padding: 10px 0;
  opacity: 0;
  transform: translateY(14px);
  transition: color 0.18s ease, opacity 0.4s ease, transform 0.4s ease;
}
.nav-overlay.is-open .nav-overlay-links a {
  opacity: 1;
  transform: translateY(0);
}
.nav-overlay.is-open .nav-overlay-links a:nth-child(1) { transition-delay: 0.05s; }
.nav-overlay.is-open .nav-overlay-links a:nth-child(2) { transition-delay: 0.1s; }
.nav-overlay.is-open .nav-overlay-links a:nth-child(3) { transition-delay: 0.15s; }
.nav-overlay.is-open .nav-overlay-links a:nth-child(4) { transition-delay: 0.2s; }
.nav-overlay-links a:hover,
.nav-overlay-links a[aria-current="page"] {
  color: var(--text);
}
.nav-overlay-links a[aria-current="page"] { color: var(--accent); }

.nav-overlay-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.nav-overlay-footer a {
  font-size: 0.9rem;
  color: var(--text-muted);
}
.nav-overlay-footer a:hover { color: var(--accent); }

.nav-overlay-social {
  display: flex;
  gap: 24px;
}

body.nav-is-open { overflow: hidden; }

/* ---------- Hero ---------- */
.hero {
  padding: 100px 0 88px;
}

.hero h1 {
  font-size: clamp(2.6rem, 7vw, 5rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.02;
  max-width: 17ch;
}

.hero-tagline {
  margin-top: 32px;
  font-size: clamp(1.05rem, 1.6vw, 1.3rem);
  color: var(--text-muted);
  max-width: 60ch;
  line-height: 1.65;
}

.hero-actions {
  margin-top: 44px;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 9999px;
  font-size: 0.92rem;
  font-weight: 500;
  border: 1px solid var(--border);
  transition: border-color 0.18s ease, color 0.18s ease, background 0.18s ease, transform 0.18s ease;
}
.btn:hover { border-color: var(--accent-dim); color: var(--accent); transform: translateY(-1px); }

.btn-icon {
  width: 19px;
  height: 19px;
  flex-shrink: 0;
  fill: currentColor;
}

.btn-primary {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}
.btn-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
  box-shadow: 0 0 28px rgba(var(--accent-rgb), 0.35);
}

/* Inert placeholder for a link that doesn't exist yet */
.btn-disabled {
  cursor: default;
  color: var(--text-faint);
  background: var(--bg-raised);
  border-style: dashed;
  border-color: var(--border-strong);
}
.btn-disabled:hover {
  border-color: var(--border-strong);
  color: var(--text-faint);
  transform: none;
}

/* ---------- Section scaffolding ---------- */
.section {
  padding: 88px 0;
  border-top: 1px solid var(--border);
}

.section-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 48px;
}

.section-heading h2 {
  font-size: clamp(1.6rem, 3.2vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.section-heading .section-link {
  font-size: 0.9rem;
  color: var(--text-muted);
  white-space: nowrap;
}
.section-heading .section-link:hover { color: var(--accent); }

.section-lead {
  color: var(--text-muted);
  max-width: 68ch;
  margin-bottom: 48px;
  font-size: 1.05rem;
}

/* ---------- Project cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

@media (max-width: 800px) {
  .card-grid { grid-template-columns: 1fr; }
}

.card {
  display: block;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-card);
  border-radius: 24px;
  padding: 40px;
  transition: border-color 0.25s ease, transform 0.25s ease, background 0.25s ease, box-shadow 0.25s ease;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(420px circle at var(--mx, 50%) var(--my, 50%), rgba(var(--accent-rgb), 0.14), transparent 70%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

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

.card > * {
  position: relative;
  z-index: 1;
}

.card:hover {
  border-color: var(--accent-dim);
  transform: translateY(-4px);
  background: var(--bg-raised);
  box-shadow: 0 14px 32px -16px rgba(var(--accent-rgb), 0.35), 0 0 0 1px rgba(var(--accent-rgb), 0.3);
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.03em;
  color: var(--text-faint);
  margin-bottom: 24px;
}
.card-meta .dot { color: var(--accent-dim); }

.card h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 14px;
  letter-spacing: -0.015em;
}

.card p {
  color: var(--text-muted);
  font-size: 0.98rem;
}

.card-cta {
  margin-top: 28px;
  font-size: 0.88rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}
.card:hover .card-cta { color: var(--accent); }

/* ---------- Skills ---------- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px 40px;
}

@media (max-width: 900px) {
  .skills-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .skills-grid { grid-template-columns: 1fr; }
}

.skill-group h3 {
  font-size: 0.85rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-faint);
  margin-bottom: 16px;
  font-weight: 500;
}

.skill-group ul li {
  color: var(--text);
  font-size: 1.02rem;
  padding: 10px 0;
  border-top: 1px solid var(--divider);
}
.skill-group ul li:first-child { border-top: none; }

/* ---------- Experience ---------- */
.experience-list {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.experience-item {
  position: relative;
  padding-left: 32px;
}

.experience-item::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--accent);
}

.experience-item::after {
  content: "";
  position: absolute;
  left: 8px;
  top: 20px;
  bottom: -48px;
  width: 1px;
  background: var(--border);
}

.experience-item:last-child::after { display: none; }

.experience-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 24px;
}

.experience-top h3 {
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.experience-date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-faint);
  white-space: nowrap;
}

.experience-meta {
  margin-top: 4px;
  margin-bottom: 16px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.experience-bullets {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.experience-bullets li {
  position: relative;
  padding-left: 18px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.experience-bullets li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent-dim);
}

@media (max-width: 600px) {
  .experience-top { flex-direction: column; }
}

/* ---------- Page header (non-home pages) ---------- */
.page-header {
  padding: 88px 0 56px;
}

.page-header .eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}

.page-header h1 {
  font-size: clamp(2.1rem, 5vw, 3.4rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  max-width: 20ch;
}

.page-header p {
  margin-top: 22px;
  color: var(--text-muted);
  max-width: 62ch;
  font-size: 1.05rem;
}

.page-header-actions {
  margin-top: 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.page-header-note {
  margin-top: 16px;
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text-faint);
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 14px;
}

/* Scoped to out-specify the generic `.page-header p` rule above */
.page-header .page-header-callout {
  margin-top: 20px;
  max-width: 62ch;
  font-size: 0.92rem;
  line-height: 1.6;
  color: var(--text-muted);
  border-left: 2px solid var(--accent-dim);
  padding: 2px 0 2px 16px;
}
.page-header .page-header-callout strong { color: var(--text); font-weight: 600; }

/* ---------- About page ---------- */
.prose {
  max-width: 68ch;
  font-size: 1.08rem;
  color: var(--text-muted);
}
.prose p { margin-bottom: 24px; }
.prose strong { color: var(--text); font-weight: 600; }

/* ---------- Project detail ---------- */
.detail-meta-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 28px 56px;
  padding-bottom: 40px;
  margin-bottom: 48px;
  border-bottom: 1px solid var(--border);
}

.detail-meta-item {
  flex: 1 1 220px;
}

.detail-meta-item dt {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-bottom: 8px;
}
.detail-meta-item dd {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.55;
}

.detail-body h2 {
  font-size: 1.3rem;
  font-weight: 600;
  margin: 44px 0 16px;
  letter-spacing: -0.015em;
}
.detail-body h2:first-child { margin-top: 0; }

.detail-body p {
  color: var(--text-muted);
  font-size: 1.02rem;
  max-width: 70ch;
  margin-bottom: 4px;
}

.project-nav {
  display: flex;
  justify-content: space-between;
  padding: 40px 0;
  border-top: 1px solid var(--border);
  margin-top: 24px;
  font-size: 0.92rem;
  color: var(--text-muted);
}
.project-nav a:hover { color: var(--accent); }

/* ---------- Contact ---------- */
.contact-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 480px;
  margin-top: 8px;
}

.contact-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 0;
  border-top: 1px solid var(--border);
  font-size: 1.05rem;
}
.contact-list a:last-child { border-bottom: 1px solid var(--border); }
.contact-list a:hover { color: var(--accent); }

.contact-list .arrow {
  color: var(--text-faint);
  transition: transform 0.18s ease, color 0.18s ease;
}
.contact-list a:hover .arrow { color: var(--accent); transform: translateX(4px); }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 64px 0 32px;
}

.footer-columns {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  padding-bottom: 48px;
}

@media (max-width: 700px) {
  .footer-columns { grid-template-columns: 1fr; gap: 32px; }
}

.footer-col h3 {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-faint);
  margin-bottom: 18px;
  font-weight: 500;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col a {
  font-size: 0.95rem;
  color: var(--text-muted);
}
.footer-col a:hover { color: var(--accent); }

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.footer-bottom a {
  font-weight: 600;
  color: var(--text);
}
.footer-bottom a:hover { color: var(--accent); }

.footer-bottom-right {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-note {
  font-size: 0.85rem;
  color: var(--text-faint);
}

.footer-social {
  display: flex;
  gap: 14px;
}

.footer-social a {
  display: inline-flex;
  color: var(--text-muted);
  font-weight: 400;
}
.footer-social a:hover { color: var(--accent); }
.footer-social svg { width: 18px; height: 18px; }

/* ---------- Scroll reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .nav-overlay-links a { opacity: 1; transform: none; }
  .card, .btn, .btn-primary { transition: none; }
}