/* --- Variables --- */
:root {
  --bg: #0b0b0f;
  --bg-elevated: #12121a;
  --surface: #16161f;
  --text: #e4e4e7;
  --text-muted: #71717a;
  --accent: #22d3ee;
  --accent-dim: #0891b2;
  --border: #27272a;
  --font-mono: "JetBrains Mono", ui-monospace, monospace;
  --font-sans: "Space Grotesk", system-ui, sans-serif;
  --radius: 6px;
  --transition: 0.2s ease;
}

/* --- Reset & base --- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
  overflow-x: hidden;
}

/* --- Background effects --- */
.noise {
  display: none;
}

.grid-bg {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    linear-gradient(rgba(39, 39, 42, 0.35) 1px, transparent 1px),
    linear-gradient(90deg, rgba(39, 39, 42, 0.35) 1px, transparent 1px);
  background-size: 40px 40px;
  opacity: 0.8;
}

/* --- Layout --- */
.header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(11, 11, 15, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
  font-size: 1.1rem;
}
.nav-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 2rem;
}
.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-family: var(--font-mono);
  text-transform: lowercase;
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--accent); }
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text-muted);
  border-radius: 1px;
}

main {
  position: relative;
  z-index: 1;
  max-width: 860px;
  margin: 0 auto;
  padding: 4rem 1.5rem 6rem;
}

/* --- Hero --- */
.hero { padding: 2rem 0 4rem; }
.hero-prefix {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}
.cursor-blink { color: var(--accent); }
.hero-name {
  font-family: var(--font-sans);
  font-size: clamp(2.5rem, 6vw, 3.5rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  margin: 0 0 0.25rem;
  color: var(--text);
}
.hero-role {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--accent);
  margin: 0 0 1rem;
  min-height: 1.5em;
}
.typing-wrap .cursor {
  color: var(--accent);
  animation: blink 1s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }
.hero-tagline {
  color: var(--text-muted);
  font-size: 1rem;
  margin: 0 0 2rem;
}
.hero-tagline a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: color var(--transition), border-color var(--transition);
}
.hero-tagline a.code-link {
  color: #22c55e;
  border-color: rgba(34, 197, 94, 0.4);
}
.hero-tagline a.code-link:hover {
  color: #4ade80;
  border-color: #4ade80;
}
.hero-tagline a:hover {
  color: var(--accent);
  border-color: var(--accent);
}
.hero-cta { display: flex; gap: 1rem; flex-wrap: wrap; }
.btn {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  padding: 0.6rem 1.2rem;
  border-radius: var(--radius);
  text-decoration: none;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.btn-primary {
  background: var(--accent);
  color: var(--bg);
  border: 1px solid var(--accent);
}
.btn-primary:hover { background: var(--accent-dim); border-color: var(--accent-dim); color: #fff; }
.btn-ghost {
  color: var(--text-muted);
  border: 1px solid var(--border);
}
.btn-ghost:hover { color: var(--accent); border-color: var(--accent); }

/* --- Sections --- */
.section { padding: 4rem 0; }
.section-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: lowercase;
  margin-bottom: 1.5rem;
  letter-spacing: 0.05em;
}

/* --- About --- */
.about-grid { display: grid; gap: 2rem; }
.about-text p { margin: 0 0 1rem; color: var(--text-muted); }
.about-text strong { color: var(--text); }
.about-text a.about-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: color var(--transition), border-color var(--transition);
}
.about-text a.about-link:hover {
  color: #22c55e;
  border-color: #22c55e;
}
.code-block {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  margin: 0;
  overflow-x: auto;
  color: var(--text-muted);
}
.code-block .accent { color: var(--accent); }

/* --- Work-style lists (experience, projects, research) --- */
.work-list { list-style: none; padding: 0; margin: 0; }
.work-item {
  border-bottom: 1px solid var(--border);
  padding: 1.5rem 0;
  transition: opacity var(--transition);
}
.work-item:first-child { padding-top: 0; }
.work-header {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 1rem;
  flex-wrap: wrap;
  padding-left: 7rem;
}
.work-year {
  position: absolute;
  left: 0;
  top: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  width: 6.5rem;
  text-align: left;
  padding-left: 0.25rem;
  line-height: 1.2;
  white-space: nowrap;
}
.work-title {
  font-size: 1.1rem;
  font-weight: 500;
  margin: 0;
  flex: 1;
}
.work-title a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition);
}
.work-title a:hover {
  color: #22c55e;
}
.work-arrow {
  color: var(--accent);
  font-family: var(--font-mono);
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity var(--transition), transform var(--transition);
}
.work-item:hover .work-arrow { opacity: 1; transform: translateX(0); }
.work-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0.2rem 0 0.6rem 7rem;
}
.work-desc a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition);
}
.work-desc a:hover {
  color: #22c55e;
}
.work-tags {
  list-style: none;
  padding: 0;
  margin: 0 0 0 7rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.work-tags li {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  background: var(--surface);
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  border: 1px solid var(--border);
}
.work-link {
  margin: 0.75rem 0 0 7rem;
  font-size: 0.9rem;
}
.work-link a {
  font-family: var(--font-mono);
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}
.work-link a:hover { color: var(--accent-dim); }

/* --- Skills --- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
}
.skill-group h4 {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  text-transform: lowercase;
  margin: 0 0 0.5rem;
  letter-spacing: 0.03em;
}
.skill-group p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* --- Contact --- */
.contact { padding-bottom: 2rem; }
.contact-text { color: var(--text-muted); margin: 0 0 1.5rem; }
.contact-links {
  list-style: none;
  padding: 0;
  margin: 0 0 2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}
.contact-links a {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
}
.contact-links a:hover { color: var(--accent); }
.contact-footer {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* --- Footer --- */
.footer {
  text-align: center;
  padding: 2rem 1.5rem;
  border-top: 1px solid var(--border);
  position: relative;
  z-index: 1;
}
.footer p { margin: 0; font-size: 0.8rem; color: var(--text-muted); }
.footer p.footer-cli {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  margin: 0 0 0.5rem;
}
.footer-cli-link {
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
}
.footer-cli-link:hover {
  color: var(--accent);
}

/* --- Scroll reveal --- */
.section .section-label,
.about-grid,
.work-item,
.skills-grid,
.contact-text,
.contact-links {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.section.visible .section-label,
.section.visible .about-grid,
.section.visible .work-item,
.section.visible .skills-grid,
.section.visible .contact-text,
.section.visible .contact-links {
  opacity: 1;
  transform: translateY(0);
}
.section.visible .work-item { transition-delay: 0.05s; }
.section.visible .work-item:nth-child(2) { transition-delay: 0.1s; }
.section.visible .work-item:nth-child(3) { transition-delay: 0.15s; }
.section.visible .work-item:nth-child(4) { transition-delay: 0.2s; }

/* --- Mobile --- */
@media (max-width: 640px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .nav.open .nav-links {
    display: flex;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    padding: 1rem 1.5rem;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
    gap: 1rem;
  }
  .work-desc,
  .work-tags,
  .work-link { margin-left: 0; }
  main { padding: 2rem 1rem 4rem; }
}