/* ─── Reset & Base ─────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg:         #fafafa;
  --surface:    #ffffff;
  --border:     #e4e4e7;
  --text:       #18181b;
  --muted:      #71717a;
  --accent:     #2563eb;
  --accent-dim: #dbeafe;
  --tag-bg:     #f1f5f9;
  --tag-text:   #475569;

  --font-sans:  'Inter', system-ui, sans-serif;
  --font-mono:  'JetBrains Mono', 'Fira Code', monospace;

  --max-w:      720px;
  --nav-h:      56px;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 24px);
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ─── Nav ──────────────────────────────────────────────────── */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 250, 250, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  height: var(--nav-h);
}

nav {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-name {
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.01em;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 28px;
}

nav ul a {
  text-decoration: none;
  color: var(--muted);
  font-size: 14px;
  transition: color 0.15s;
}

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

/* ─── Layout ───────────────────────────────────────────────── */
main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 64px 24px 96px;
}

section {
  margin-bottom: 72px;
}

/* ─── Hero ─────────────────────────────────────────────────── */
.hero {
  padding: 48px 0 16px;
  margin-bottom: 72px;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 12px;
}

.hero .tagline {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  margin-bottom: 20px;
}

.hero p {
  color: var(--muted);
  max-width: 560px;
  font-size: 15px;
}

/* ─── Section headings ─────────────────────────────────────── */
.section-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 8px;
}

h2 {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

p {
  color: var(--muted);
  margin-bottom: 16px;
}

p:last-child {
  margin-bottom: 0;
}

/* ─── Project cards ────────────────────────────────────────── */
.projects-grid {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 24px;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.card:hover {
  border-color: #c4b5fd;
  box-shadow: 0 2px 12px rgba(37, 99, 235, 0.06);
}

.card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.card p {
  font-size: 14px;
  margin-bottom: 16px;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tag {
  font-family: var(--font-mono);
  font-size: 11px;
  background: var(--tag-bg);
  color: var(--tag-text);
  padding: 3px 8px;
  border-radius: 4px;
}

/* ─── Coursework ───────────────────────────────────────────── */
.course-group {
  margin-bottom: 28px;
}

.course-group h3 {
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-family: var(--font-mono);
  margin-bottom: 12px;
}

.course-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.course-list li {
  font-size: 14px;
  color: var(--text);
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.course-list li::before {
  content: '';
  display: inline-block;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
}

/* ─── Footer ───────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 24px;
  font-size: 13px;
  color: var(--muted);
}

/* ─── Responsive ───────────────────────────────────────────── */
@media (max-width: 600px) {
  .hero h1 { font-size: 1.6rem; }
  nav ul { gap: 16px; }
  main { padding: 40px 16px 72px; }
}