/* ── Design Tokens ── */
:root {
  --bg-page:  #f8fafc;
  --bg-card:  #ffffff;
  --bg-nav:   rgba(248, 250, 252, 0.88);
  --fg:       #0f172a;
  --fg-muted: #64748b;
  --fg-sub:   #94a3b8;
  --accent:        #1d4ed8;
  --accent-hover:  #1e40af;
  --border:   #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(15,23,42,0.08), 0 1px 2px rgba(15,23,42,0.05);
  --shadow-md: 0 4px 16px rgba(15,23,42,0.10), 0 2px 4px rgba(15,23,42,0.06);
  --r-card: 12px;
  --r-pill: 9999px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg-page:  #020617;
    --bg-card:  #0f172a;
    --bg-nav:   rgba(2, 6, 23, 0.88);
    --fg:       #f1f5f9;
    --fg-muted: #94a3b8;
    --fg-sub:   #64748b;
    --accent:        #60a5fa;
    --accent-hover:  #93c5fd;
    --border:   #1e293b;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.4);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.5);
  }
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color-scheme: light dark;
  scroll-behavior: smooth;
}
body { background: var(--bg-page); color: var(--fg); line-height: 1.6; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
ul { list-style: none; }

/* ── Nav ── */
#top-nav {
  position: sticky; top: 0; z-index: 50;
  background: var(--bg-nav);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1100px; margin: 0 auto; padding: 0 1.5rem;
  height: 60px; display: flex; align-items: center; justify-content: space-between;
}
.nav-brand {
  font-weight: 700; font-size: 1rem; letter-spacing: -0.02em; color: var(--fg);
}
.nav-links { display: flex; gap: 1.75rem; }
.nav-links a {
  font-size: 0.875rem; font-weight: 500; color: var(--fg-muted);
  transition: color 150ms;
}
.nav-links a:hover { color: var(--accent); }
.nav-toggle {
  display: none; background: none; border: none; cursor: pointer;
  color: var(--fg); padding: 4px;
}
.nav-toggle svg { width: 22px; height: 22px; }
@media (max-width: 639px) {
  .nav-toggle { display: flex; align-items: center; }
  .nav-links {
    display: none; flex-direction: column; gap: 0;
    position: absolute; top: 60px; left: 0; right: 0;
    background: var(--bg-nav); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    padding: 0.75rem 1.5rem 1rem;
  }
  .nav-links li a { display: block; padding: 0.5rem 0; font-size: 0.9375rem; }
  #top-nav[data-open="true"] .nav-links { display: flex; }
}

/* ── Section primitives ── */
.section { padding-block: 4rem; }
.section-alt { background: var(--bg-card); }
.section-inner { max-width: 1100px; margin: 0 auto; padding-inline: 1.5rem; }
.section-label {
  font-size: 0.6875rem; letter-spacing: 0.1em; text-transform: uppercase;
  font-weight: 700; color: var(--fg-muted); margin-bottom: 0.375rem;
}
.section-title {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 800; letter-spacing: -0.03em;
  color: var(--fg); margin-bottom: 2rem; line-height: 1.2;
}
.section-header {
  display: flex; align-items: baseline; justify-content: space-between;
  flex-wrap: wrap; gap: 0.5rem; margin-bottom: 2rem;
}
.section-header .section-title { margin-bottom: 0; }
.view-all {
  font-size: 0.875rem; font-weight: 500; color: var(--accent);
  white-space: nowrap; transition: color 150ms;
}
.view-all:hover { color: var(--accent-hover); }

/* ── Pills ── */
.pill {
  display: inline-flex; align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: var(--r-pill);
  font-size: 0.8125rem; font-weight: 500;
  background: var(--bg-page);
  border: 1px solid var(--border);
  color: var(--fg-muted);
}
.section-alt .pill { background: var(--bg-page); }
.pill-accent {
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  color: var(--accent);
  border-color: color-mix(in srgb, var(--accent) 28%, transparent);
}
.pill-row { display: flex; flex-wrap: wrap; gap: 0.375rem; margin-top: 0.75rem; }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.5rem 1.125rem;
  border-radius: 8px; font-size: 0.875rem; font-weight: 500;
  border: 1px solid var(--border);
  background: var(--bg-card); color: var(--fg);
  transition: background 150ms, box-shadow 150ms, border-color 150ms;
  cursor: pointer; white-space: nowrap;
}
.btn:hover { background: var(--border); }
.btn-primary {
  background: var(--accent); color: #fff; border-color: var(--accent);
}
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }

/* ── Cards ── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-card);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 200ms, transform 200ms;
}
.card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }

/* ── PwC logo light/dark swap ── */
.logo-dark { display: none; }
@media (prefers-color-scheme: dark) {
  .logo-light { display: none; }
  .logo-dark  { display: block; }
}

/* ── Sub-page hero ── */
.page-hero { padding-block: 3rem 2rem; border-bottom: 1px solid var(--border); }
.back-link {
  display: inline-flex; align-items: center; gap: 0.375rem;
  font-size: 0.875rem; font-weight: 500; color: var(--fg-muted);
  transition: color 150ms; margin-bottom: 1.5rem;
}
.back-link:hover { color: var(--accent); }
.page-hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800; letter-spacing: -0.04em; line-height: 1.1;
  margin-bottom: 0.5rem;
}
.page-hero-sub { font-size: 0.9375rem; color: var(--fg-muted); }

/* ── Timeline (shared by experience and education sub-pages) ── */
.timeline { display: flex; flex-direction: column; gap: 0; }
.timeline-item {
  position: relative;
  padding: 1.75rem 1.75rem 1.75rem 2.25rem;
  border-left: 2px solid var(--border);
  margin-left: 0.5rem;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: -5px; top: 1.875rem;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-page);
}
.timeline-item:last-child { border-left-color: transparent; }
.timeline-item--muted::before { background: var(--border); }
.tl-role { font-size: 1.0625rem; font-weight: 700; color: var(--fg); line-height: 1.3; }
.tl-company { font-size: 0.875rem; font-weight: 600; color: var(--accent); margin-top: 0.2rem; }
.tl-meta { font-size: 0.8125rem; color: var(--fg-sub); margin-top: 0.25rem; }
.tl-desc { font-size: 0.875rem; color: var(--fg-muted); margin-top: 0.75rem; line-height: 1.7; }
.tl-desc ul { padding-left: 1.25rem; list-style: disc; }
.tl-desc li { margin-bottom: 0.25rem; }
.tl-logo {
  width: 48px; height: 48px; object-fit: contain;
  border-radius: 8px; border: 1px solid var(--border);
  background: var(--bg-page); padding: 6px;
  float: right; margin: 0 0 0.5rem 1rem;
}
.timeline-divider {
  display: flex; align-items: center; gap: 1rem;
  margin: 1rem 0 0 0.5rem;
  font-size: 0.75rem; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.1em; color: var(--fg-sub);
}
.timeline-divider::after { content: ''; flex: 1; height: 1px; background: var(--border); }

/* ── Footer ── */
footer {
  padding-block: 2.5rem;
  border-top: 1px solid var(--border);
  background: var(--bg-card);
}
.footer-inner {
  max-width: 1100px; margin: 0 auto; padding-inline: 1.5rem;
  display: flex; flex-wrap: wrap; justify-content: space-between;
  align-items: center; gap: 0.5rem;
}
.footer-copy { font-size: 0.8125rem; color: var(--fg-muted); }
.footer-sub  { font-size: 0.8125rem; color: var(--fg-sub); }