/* ---------------------------------------------------------------
   jayanaka.dev — personal site
   Design tokens
---------------------------------------------------------------- */
:root {
  --bg: #fdfdfc;
  --bg-alt: #f4f4f0;
  --surface: #ffffff;
  --text: #1a1c1e;
  --text-muted: #5c6167;
  --accent: #0d5c63;
  --accent-strong: #0a474d;
  --accent-soft: #e3efef;
  --border: #e3e2dd;
  --code-bg: #14262a;
  --code-text: #d6e6e4;
  --max-width: 68rem;
  --radius: 10px;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas,
    "Liberation Mono", monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101314;
    --bg-alt: #16191b;
    --surface: #1a1e20;
    --text: #e8e8e6;
    --text-muted: #9ba1a6;
    --accent: #5ec2c9;
    --accent-strong: #8ad4d9;
    --accent-soft: #17282a;
    --border: #272c2f;
    --code-bg: #0c1a1d;
    --code-text: #c9dedd;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

code, pre { font-family: var(--font-mono); }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---------------------------------------------------------------
   Header / nav
---------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 3.5rem;
}

.brand {
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.01em;
}
.brand:hover { text-decoration: none; color: var(--accent); }

.site-nav a {
  color: var(--text-muted);
  margin-left: 1.25rem;
  font-size: 0.95rem;
}
.site-nav a:hover { color: var(--accent); text-decoration: none; }

/* ---------------------------------------------------------------
   Hero
---------------------------------------------------------------- */
.hero { padding: 5rem 0 3.5rem; }

.hero-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2.5rem;
  align-items: center;
}

.hero h1 {
  font-size: clamp(2.1rem, 5vw, 3rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.75rem;
}

.hero .kicker {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 0 0 0.75rem;
}

.hero .lede {
  color: var(--text-muted);
  font-size: 1.15rem;
  max-width: 44rem;
  margin: 0 0 1.5rem;
}

.hero-photo {
  width: 190px;
  height: 190px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--border);
}

.hero-links { display: flex; flex-wrap: wrap; gap: 0.6rem; }

.btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text);
  font-size: 0.92rem;
  background: var(--surface);
}
.btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.btn-primary:hover { background: var(--accent-strong); color: #fff; }

@media (prefers-color-scheme: dark) {
  .btn-primary { color: #0c1a1d; }
  .btn-primary:hover { color: #0c1a1d; }
}

/* ---------------------------------------------------------------
   Sections
---------------------------------------------------------------- */
section { padding: 3.5rem 0; }
section.alt { background: var(--bg-alt); }

.section-title {
  font-size: 1.6rem;
  letter-spacing: -0.01em;
  margin: 0 0 1.5rem;
}
.section-title::after {
  content: "";
  display: block;
  width: 2.5rem;
  height: 3px;
  margin-top: 0.5rem;
  background: var(--accent);
  border-radius: 2px;
}

.prose { max-width: 46rem; }
.prose p { margin: 0 0 1rem; }

/* ---------------------------------------------------------------
   Sigil feature card
---------------------------------------------------------------- */
.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  display: grid;
  gap: 1.75rem;
  grid-template-columns: 1.2fr 1fr;
  align-items: center;
}

.feature-card h3 {
  margin: 0 0 0.25rem;
  font-size: 1.45rem;
}

.feature-tagline {
  color: var(--accent);
  font-weight: 600;
  margin: 0 0 1rem;
}

.terminal {
  background: var(--code-bg);
  color: var(--code-text);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  font-size: 0.88rem;
  line-height: 1.7;
  overflow-x: auto;
}
.terminal .dim { opacity: 0.55; }
.terminal .accent { color: #7fd8de; }

.stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 1.25rem;
}
.stat {
  border-left: 3px solid var(--accent);
  padding-left: 0.75rem;
}
.stat .num {
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.stat .label {
  color: var(--text-muted);
  font-size: 0.85rem;
  line-height: 1.4;
}

/* ---------------------------------------------------------------
   Research / cards
---------------------------------------------------------------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1.25rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.4rem 1.5rem;
}
.card h3 { margin: 0 0 0.5rem; font-size: 1.1rem; }
.card p { margin: 0; color: var(--text-muted); font-size: 0.95rem; }

/* ---------------------------------------------------------------
   Publications
---------------------------------------------------------------- */
.pub-list { list-style: none; margin: 0; padding: 0; }

.pub {
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border);
}
.pub:last-child { border-bottom: none; }

.pub .pub-title {
  font-weight: 600;
  font-size: 1.05rem;
  margin: 0 0 0.2rem;
}
.pub .pub-authors {
  color: var(--text-muted);
  font-size: 0.93rem;
  margin: 0 0 0.2rem;
}
.pub .pub-venue {
  font-size: 0.9rem;
  margin: 0 0 0.4rem;
  color: var(--text);
}
.pub .pub-venue .venue-name { color: var(--accent); font-weight: 600; }
.pub .pub-links { font-size: 0.88rem; }
.pub .pub-links a { margin-right: 0.9rem; }

.pub-note {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 1rem;
}

/* ---------------------------------------------------------------
   Footer
---------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2.5rem 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}
.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: space-between;
}
.footer-links a { color: var(--text-muted); margin-right: 1rem; }
.footer-links a:hover { color: var(--accent); }

/* ---------------------------------------------------------------
   Responsive
---------------------------------------------------------------- */
@media (max-width: 720px) {
  .hero { padding: 3rem 0 2.5rem; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-photo { width: 140px; height: 140px; order: -1; }
  .feature-card { grid-template-columns: 1fr; }
  .stats-row { grid-template-columns: 1fr; }
  .site-nav { display: none; }
}