:root {
  --bg: #ffffff;
  --bg-alt: #f6f7fb;
  --text: #14161a;
  --text-muted: #5b6270;
  --border: #e6e8ee;
  --accent: #2952e3;
  --accent-soft: #eef1fd;
  --radius: 14px;
  --max-width: 1080px;
  font-size: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 0.5rem;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.75rem, 6vw, 4.5rem); font-weight: 800; }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.5rem); }
h3 { font-size: 1.15rem; }
h4 { font-size: 1.05rem; margin-bottom: 0.2rem; }

p { margin: 0 0 1rem; color: var(--text-muted); }

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

sup { font-size: 0.6em; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}
.logo .dot { color: var(--accent); }

.nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color 0.15s ease;
}
.nav a:hover { color: var(--text); }

.nav-cta {
  color: var(--accent) !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  display: block;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

/* Hero */
.hero {
  padding: 6rem 0 2.5rem;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 1rem;
}

.hero-sub {
  max-width: 620px;
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-top: 1.25rem;
}

.hero-sub strong { color: var(--text); }

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin: 2rem 0 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.8rem 1.5rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.92rem;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.btn-primary {
  background: var(--text);
  color: #fff;
}
.btn-primary:hover { transform: translateY(-2px); background: var(--accent); }

.btn-ghost {
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--accent); color: var(--accent); }

/* Sections */
.section {
  padding: 5.5rem 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-kicker {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.lead {
  max-width: 640px;
  font-size: 1.05rem;
}

.block-title {
  margin-bottom: 1.25rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--border);
}

.grid-2 {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 3.5rem;
  margin-top: 2.5rem;
}

/* Timeline */
.timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 2px solid var(--border);
}

.timeline-item {
  position: relative;
  padding: 0 0 2rem 1.75rem;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -6.5px;
  top: 4px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--accent);
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-date {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 0.25rem;
}

.timeline-org {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
}

.timeline-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
}

.timeline-note {
  font-size: 0.85rem;
  opacity: 0.8;
}

.timeline-exp {
  margin-top: 2.5rem;
  max-width: 760px;
}

/* Tags */
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.tag {
  font-size: 0.82rem;
  font-weight: 500;
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
}

/* Cards */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(20, 22, 26, 0.08);
}

.card-tag {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.card p:not(.card-tag):not(.card-skills) {
  font-size: 0.92rem;
}

.card-skills {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 1rem;
  margin-bottom: 0;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

/* Video section */
.video-stats-line {
  font-size: 0.85rem;
  color: var(--text-muted);
  opacity: 0.85;
  margin: 1.5rem 0 2.5rem;
}

.video-list {
  border-top: 1px solid var(--border);
  margin-bottom: 2.5rem;
}

.video-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border);
}

.video-title {
  font-weight: 600;
  font-size: 0.98rem;
}

.video-meta {
  font-size: 0.82rem;
  color: var(--text-muted);
  white-space: nowrap;
}

/* Contact */
.contact-section { text-align: left; }

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
}

.contact-link {
  padding: 0.85rem 1.5rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.92rem;
  transition: transform 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.contact-link:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  color: var(--accent);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-inner a:hover { color: var(--accent); }

/* Reveal animation */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Responsive */
@media (max-width: 860px) {
  .grid-2 { grid-template-columns: 1fr; gap: 2.5rem; }
  .cards { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .nav {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 0.5rem 1.5rem 1rem;
    display: none;
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 0.75rem 0; width: 100%; }
  .nav-toggle { display: flex; }
  .hero { padding: 3.5rem 0 3rem; }
  .section { padding: 3.5rem 0; }
}