:root {
  --bg: #061114;
  --bg-soft: #0c1d22;
  --panel: #10272e;
  --panel-2: #0f2228;
  --text: #eef8f8;
  --muted: #a9bdc0;
  --soft: #d5e3e5;
  --accent: #5eead4;
  --accent-2: #7dd3fc;
  --line: rgba(255, 255, 255, 0.1);
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.28);
  --radius-lg: 28px;
  --radius-md: 18px;
  --max: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background:
    radial-gradient(circle at 15% 0%, rgba(94, 234, 212, 0.14), transparent 34%),
    radial-gradient(circle at 85% 10%, rgba(125, 211, 252, 0.12), transparent 30%),
    var(--bg);
  color: var(--text);
  line-height: 1.6;
}

a { color: inherit; text-decoration: none; }
p { margin: 0 0 1rem; }
h1, h2, h3 { margin: 0; line-height: 1.08; letter-spacing: -0.035em; }
h1 { font-size: clamp(3rem, 8vw, 6.7rem); max-width: 920px; }
h2 { font-size: clamp(2rem, 4vw, 3.7rem); }
h3 { font-size: 1.25rem; }
ul { margin: 0; padding: 0; list-style: none; }

.container {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

.section { padding: 112px 0; }
.section.muted { background: rgba(255, 255, 255, 0.03); border-block: 1px solid var(--line); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(6, 17, 20, 0.82);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
}
.nav {
  height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 750;
  letter-spacing: -0.04em;
  font-size: 1.08rem;
}
.brand span span { color: var(--accent); }
.brand-mark {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(94, 234, 212, 0.2), rgba(125, 211, 252, 0.16));
  border: 1px solid rgba(94, 234, 212, 0.32);
  color: var(--accent);
  box-shadow: 0 10px 30px rgba(94, 234, 212, 0.08);
}
.nav-links { display: flex; align-items: center; gap: 24px; color: var(--muted); font-size: 0.95rem; }
.nav-links a:hover { color: var(--text); }

.hero { padding-top: 130px; }
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
  gap: 52px;
  align-items: center;
}
.eyebrow {
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.76rem;
  font-weight: 800;
  margin-bottom: 18px;
}
.hero-text {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  color: var(--soft);
  max-width: 760px;
  margin-top: 28px;
}
.actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 999px;
  font-weight: 700;
  border: 1px solid transparent;
  transition: transform .2s ease, border-color .2s ease, background .2s ease;
}
.button:hover { transform: translateY(-2px); }
.button.primary { background: var(--accent); color: #052222; }
.button.secondary { border-color: var(--line); color: var(--text); background: rgba(255,255,255,0.03); }
.supporting { color: var(--muted); margin-top: 24px; max-width: 620px; }

.hero-card {
  position: relative;
  min-height: 430px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.09), rgba(255,255,255,0.035)),
    var(--panel);
  box-shadow: var(--shadow);
  padding: 32px;
  display: grid;
  align-content: center;
  gap: 24px;
  overflow: hidden;
}
.hero-card:before {
  content: "";
  position: absolute;
  inset: -1px;
  background: radial-gradient(circle at 50% 50%, rgba(94,234,212,0.18), transparent 56%);
  pointer-events: none;
}
.node-card, .secure-link {
  position: relative;
  z-index: 1;
}
.node-card {
  padding: 24px;
  border-radius: 22px;
  background: rgba(6,17,20,0.64);
  border: 1px solid rgba(94,234,212,0.18);
  display: grid;
  gap: 4px;
}
.node-card strong { font-size: 1.4rem; }
.node-card small { color: var(--muted); }
.node-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 28px var(--accent);
  margin-bottom: 10px;
}
.secure-link { display: grid; place-items: center; gap: 8px; color: var(--muted); }
.secure-link span { width: 80%; height: 1px; background: linear-gradient(90deg, transparent, var(--accent), transparent); }
.secure-link p { margin: 0; font-size: 0.9rem; }

.split, .architecture-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 70px;
  align-items: start;
}
.prose { color: var(--soft); font-size: 1.08rem; }
.prose p:last-child { margin-bottom: 0; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.feature-card, .stack-card, .scenario-card, .cards-four article, .final-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.045);
  padding: 28px;
}
.feature-card.wide { grid-column: span 3; padding: 42px; }
.feature-card p, .scenario-card p, .cards-four p { color: var(--muted); margin-top: 12px; }

.stack-card { background: linear-gradient(180deg, rgba(94,234,212,0.08), rgba(255,255,255,0.04)); }
.stack-card h3 { margin-bottom: 22px; color: var(--accent); }
.stack-card li {
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  color: var(--soft);
}
.stack-card li:last-child { border-bottom: 0; }

.section-heading {
  max-width: 780px;
  margin: 0 auto 46px;
  text-align: center;
}
.section-heading p:not(.eyebrow) { color: var(--soft); font-size: 1.08rem; margin-top: 18px; }
.scenario-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.mini-diagram {
  margin: 22px 0;
  padding: 22px;
  border-radius: 16px;
  background: rgba(6,17,20,0.55);
  color: var(--soft);
  font-weight: 650;
}
.mini-diagram span { color: var(--accent); margin: 0 8px; }
.center-note {
  text-align: center;
  color: var(--accent);
  font-weight: 800;
  margin-top: 34px;
}

.check-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}
.check-grid span, .principles span {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 18px;
  background: rgba(255,255,255,0.04);
  color: var(--soft);
}
.check-grid span:before, .principles span:before {
  content: "✓";
  color: var(--accent);
  margin-right: 10px;
}
.cards-four { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.principles { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }

.final-cta { padding-top: 40px; }
.final-card {
  text-align: center;
  max-width: 920px;
  background:
    radial-gradient(circle at 50% 0%, rgba(94,234,212,0.13), transparent 45%),
    rgba(255,255,255,0.045);
}
.final-card > p { color: var(--soft); font-size: 1.08rem; }
.question-list {
  display: grid;
  gap: 8px;
  margin: 28px auto;
  max-width: 720px;
}
.question-list p {
  margin: 0;
  padding: 14px 18px;
  border-radius: 14px;
  background: rgba(6,17,20,0.46);
  color: var(--soft);
}
.actions.centered { justify-content: center; }

.site-footer {
  border-top: 1px solid var(--line);
  padding: 42px 0;
  color: var(--muted);
}
.footer-grid { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: 32px; }
.footer-brand { margin-bottom: 12px; }
.footer-title { color: var(--text); font-weight: 800; margin-bottom: 8px; }
.site-footer a { color: var(--accent); }
.footer-credit {
  border-top: 1px solid var(--line);
  padding: 18px 0;
  font-size: 0.82rem;
  color: var(--muted);
}
.footer-credit p { margin: 0; display: flex; align-items: center; gap: 6px; }
.footer-credit img { vertical-align: middle; opacity: 0.85; }
.error-page { min-height: 60vh; }

@media (max-width: 900px) {
  .nav-links { display: none; }
  .hero-grid, .split, .architecture-grid, .scenario-grid, .footer-grid { grid-template-columns: 1fr; }
  .feature-grid, .check-grid, .cards-four, .principles { grid-template-columns: 1fr; }
  .feature-card.wide { grid-column: span 1; padding: 28px; }
  .section { padding: 78px 0; }
  .hero { padding-top: 92px; }
  .hero-card { min-height: 360px; }
}

@media (max-width: 520px) {
  .container { width: min(100% - 28px, var(--max)); }
  .actions { flex-direction: column; }
  .button { width: 100%; }
  h1 { font-size: clamp(2.6rem, 15vw, 4rem); }
}