:root {
  --ink: #0b0d10;
  --paper: #e8eaed;
  --signal: #1f6bff;
  --signal-hot: #3b7cff;
  --muted: #5c6570;
  --line: rgba(11, 13, 16, 0.12);
  --font-display: "Syne", sans-serif;
  --font-body: "DM Sans", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--font-body);
  background: var(--paper);
  position: relative;
  overflow-x: hidden;
}

.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(1100px 640px at 8% -8%, rgba(31, 107, 255, 0.18), transparent 55%),
    radial-gradient(800px 520px at 92% 0%, rgba(11, 13, 16, 0.1), transparent 50%),
    linear-gradient(160deg, #f2f4f7 0%, #e4e8ee 48%, #d7dde6 100%);
  animation: drift 18s ease-in-out infinite alternate;
}
@keyframes drift {
  from { transform: scale(1) translate3d(0, 0, 0); }
  to { transform: scale(1.04) translate3d(-1.5%, 1%, 0); }
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.75rem;
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(232, 234, 237, 0.78);
  border-bottom: 1px solid var(--line);
  z-index: 10;
}
.wordmark {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.03em;
  color: var(--ink);
  text-decoration: none;
}
.nav-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, color 0.25s ease;
}
.nav-link:hover { border-color: var(--signal); color: var(--signal); }

.hero {
  min-height: calc(100vh - 64px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 4rem 1.75rem 5rem;
  max-width: 920px;
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.hero.in { opacity: 1; transform: none; }
.brand {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(3.2rem, 10vw, 6.5rem);
  letter-spacing: -0.045em;
  line-height: 0.92;
  margin-bottom: 1.25rem;
}
.hero h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}
.lede {
  font-size: 1.125rem;
  line-height: 1.55;
  color: var(--muted);
  max-width: 34rem;
  margin-bottom: 2rem;
}
.cta-row { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.9rem 1.35rem;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border-radius: 4px;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease;
}
.cta.primary {
  background: var(--ink);
  color: #f4f6f8;
}
.cta.primary:hover { background: var(--signal); color: #fff; transform: translateY(-2px); }
.cta.ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
}
.cta.ghost:hover { border-color: var(--signal); color: var(--signal); }

.section {
  padding: 4.5rem 1.75rem;
  max-width: 720px;
  border-top: 1px solid var(--line);
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.section.in { opacity: 1; transform: none; }
.section h2 {
  font-family: var(--font-display);
  font-size: 1.75rem;
  letter-spacing: -0.03em;
  margin-bottom: 0.85rem;
}
.section p {
  font-size: 1.05rem;
  line-height: 1.6;
  color: var(--muted);
  margin-bottom: 1.25rem;
}
.section.final .cta { margin-top: 0.5rem; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  padding: 2rem 1.75rem 3rem;
  border-top: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--muted);
}
footer a { color: var(--ink); font-weight: 600; }

@media (max-width: 640px) {
  .brand { font-size: 3rem; }
  .nav { padding: 1rem 1.1rem; }
  .hero, .section { padding-left: 1.1rem; padding-right: 1.1rem; }
}