:root {
  --bg: #0b1020;
  --bg-soft: #111831;
  --panel: #151d38;
  --text: #e6ebf5;
  --muted: #9aa7c2;
  --accent: #5eead4;
  --accent-2: #7c9cff;
  --border: #223052;
  --radius: 14px;
  --max: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  background: radial-gradient(1200px 600px at 80% -10%, #16203f 0%, var(--bg) 55%);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* HEADER */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(10px);
  background: rgba(11, 16, 32, 0.72);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 800; font-size: 20px; letter-spacing: 0.5px; }
.brand-dot { color: var(--accent); }
.nav-links { display: flex; gap: 22px; list-style: none; margin: 0; padding: 0; font-size: 14px; font-weight: 500; }
.nav-links a { color: var(--muted); transition: color 0.2s; }
.nav-links a:hover { color: var(--text); }
.nav-cta {
  color: var(--accent) !important;
  border: 1px solid var(--accent);
  padding: 6px 14px;
  border-radius: 999px;
}
.nav-cta:hover { background: var(--accent); color: #06231f !important; }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 22px; height: 2px; background: var(--text); border-radius: 2px; }

/* HERO */
.hero {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  padding: 90px 24px 70px;
}
.eyebrow { color: var(--accent); font-family: "JetBrains Mono", monospace; font-size: 14px; margin: 0 0 14px; }
.hero h1 { font-size: clamp(36px, 6vw, 60px); line-height: 1.05; margin: 0 0 18px; font-weight: 800; }
.hero-sub { color: var(--muted); font-size: 18px; max-width: 46ch; margin: 0 0 28px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 22px; }

.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  transition: transform 0.15s, background 0.2s, border-color 0.2s;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #06231f; }
.btn-ghost { border: 1px solid var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); }

.hero-links { display: flex; gap: 20px; font-size: 14px; font-weight: 500; }
.hero-links a { color: var(--muted); border-bottom: 1px solid transparent; }
.hero-links a:hover { color: var(--accent); border-color: var(--accent); }

.hero-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 30px 60px -30px rgba(0,0,0,0.6);
}
.code-block {
  margin: 0;
  font-family: "JetBrains Mono", monospace;
  font-size: 14px;
  color: var(--text);
  white-space: pre-wrap;
  line-height: 1.8;
}
.c-key { color: #c792ea; }
.c-prop { color: var(--accent-2); }
.c-str { color: var(--accent); }

/* SECTIONS */
.section { padding: 70px 24px; }
.section-title { font-size: 26px; font-weight: 700; margin: 0 0 36px; display: flex; align-items: baseline; gap: 12px; }
.section-title span { color: var(--accent); font-family: "JetBrains Mono", monospace; font-size: 18px; }

/* ABOUT */
.about-grid { display: grid; grid-template-columns: 1.4fr 0.8fr; gap: 40px; }
.about-grid p { color: var(--muted); margin: 0 0 16px; }
.about-facts { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.about-facts li { display: flex; flex-direction: column; border-left: 2px solid var(--accent); padding-left: 14px; }
.about-facts strong { font-size: 13px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; }

/* TIMELINE */
.timeline { display: grid; gap: 26px; }
.timeline-item { display: grid; grid-template-columns: 180px 1fr; gap: 24px; background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.timeline-meta { color: var(--accent); font-family: "JetBrains Mono", monospace; font-size: 14px; }
.timeline-body h3 { margin: 0 0 10px; font-size: 18px; }
.timeline-body .at { color: var(--muted); font-weight: 500; }
.timeline-body p, .timeline-body li { color: var(--muted); }
.timeline-body ul { margin: 10px 0 0; padding-left: 18px; }

/* CARDS */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; display: flex; flex-direction: column; transition: transform 0.15s, border-color 0.2s; }
.card:hover { transform: translateY(-4px); border-color: var(--accent); }
.card h3 { margin: 0 0 10px; font-size: 18px; }
.card p { color: var(--muted); flex: 1; margin: 0 0 16px; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 14px; }
.tags span { font-size: 12px; font-family: "JetBrains Mono", monospace; color: var(--accent); background: rgba(94,234,212,0.08); border: 1px solid var(--border); padding: 4px 10px; border-radius: 999px; }
.card-link { color: var(--accent); font-weight: 600; font-size: 14px; }

/* SKILLS */
.skills-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.skill-group { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; }
.skill-group h3 { margin: 0 0 14px; font-size: 16px; color: var(--accent); }
.skill-group ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.skill-group li { color: var(--muted); font-size: 14px; }

/* PUBLICATIONS */
.pub-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 18px; }
.pub-list li { display: grid; grid-template-columns: 70px 1fr; gap: 18px; border-bottom: 1px solid var(--border); padding-bottom: 18px; }
.pub-year { color: var(--accent); font-family: "JetBrains Mono", monospace; }
.pub-list h3 { margin: 0 0 4px; font-size: 17px; }
.pub-list p { margin: 0; color: var(--muted); font-size: 14px; }
.pub-list a { color: var(--accent-2); }

/* CERTIFICATIONS */
.cert-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.cert { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; text-align: center; font-size: 14px; color: var(--muted); }

/* CONTACT */
.contact { text-align: center; }
.contact-lead { color: var(--muted); max-width: 52ch; margin: 0 auto 26px; font-size: 18px; }
.contact .hero-links { justify-content: center; margin-top: 26px; }

/* FOOTER */
.site-footer { border-top: 1px solid var(--border); padding: 28px 0; margin-top: 40px; }
.site-footer p { color: var(--muted); font-size: 14px; text-align: center; margin: 0; }

/* RESPONSIVE */
@media (max-width: 860px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; gap: 0;
    background: var(--bg-soft); border-bottom: 1px solid var(--border);
    max-height: 0; overflow: hidden; transition: max-height 0.3s;
  }
  .nav-links.open { max-height: 420px; }
  .nav-links li { width: 100%; }
  .nav-links a { display: block; padding: 14px 24px; }
  .nav-cta { border: 0; border-radius: 0; }
  .hero { grid-template-columns: 1fr; padding-top: 60px; }
  .about-grid, .cards, .skills-grid, .cert-grid { grid-template-columns: 1fr; }
  .timeline-item { grid-template-columns: 1fr; }
  .cert-grid { grid-template-columns: 1fr 1fr; }
}