:root {
  --bg: #0f1115;
  --panel: #171a21;
  --panel-2: #1f2430;
  --line: #2b3243;
  --text: #e7ebf3;
  --muted: #9aa4b5;
  --accent: #6ea8fe;
  --accent-ink: #07111f;
  --ok: #5bd6a2;
  --danger: #ef7b7b;
  --radius: 16px;
  --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(900px 500px at 80% -10%, rgba(110, 168, 254, 0.16), transparent 70%),
    radial-gradient(700px 400px at 0% 20%, rgba(91, 214, 162, 0.08), transparent 70%),
    var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.55;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
code { font-family: var(--mono); font-size: 0.9em; color: #cfe0ff; }
pre { margin: 0; overflow-x: auto; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 16px; }
pre code { color: var(--text); }
h1, h2, h3 { line-height: 1.15; letter-spacing: -0.02em; }
h1 { font-size: clamp(2.2rem, 4.4vw, 3.6rem); margin: 12px 0 18px; }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.5rem); margin: 10px 0 14px; }
h3 { font-size: 1.05rem; margin: 0 0 8px; }
p { margin: 0 0 14px; }
.eyebrow { color: var(--accent); text-transform: uppercase; letter-spacing: 0.14em; font-size: 0.75rem; font-weight: 700; }
.lede { color: #c4ccda; font-size: 1.12rem; max-width: 58ch; }
.small { color: var(--muted); font-size: 0.85rem; }

.site-header {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 14px clamp(16px, 5vw, 64px);
  background: rgba(15, 17, 21, 0.86); backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 750; }
.site-header nav { display: flex; gap: 18px; flex-wrap: wrap; }
.site-header nav a { color: var(--muted); font-size: 0.9rem; }
.site-header nav a:hover { color: var(--text); }

main { max-width: 1180px; margin: 0 auto; padding: 0 clamp(16px, 5vw, 48px) 80px; }
section { padding: clamp(40px, 8vw, 90px) 0; border-bottom: 1px solid var(--line); }
.hero { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.9fr); gap: clamp(24px, 5vw, 64px); align-items: center; min-height: 76vh; }
.cta-row { display: flex; flex-wrap: wrap; gap: 10px; margin: 22px 0 14px; }
.button { display: inline-flex; align-items: center; border: 1px solid var(--line); border-radius: 10px; padding: 11px 18px; color: var(--text); background: var(--panel); font-weight: 650; }
.button.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.button:hover { text-decoration: none; transform: translateY(-1px); }

.graphic-slot {
  min-height: 360px; border: 1px dashed #3c465c; border-radius: var(--radius);
  display: grid; place-content: center; text-align: center; gap: 4px;
  background:
    linear-gradient(135deg, rgba(110, 168, 254, 0.08), rgba(91, 214, 162, 0.04)),
    repeating-linear-gradient(45deg, transparent 0 18px, rgba(255,255,255,0.02) 18px 19px);
  color: var(--muted); text-transform: uppercase; letter-spacing: 0.12em; font-size: 0.8rem;
}
.graphic-slot small { text-transform: none; letter-spacing: 0; color: #6e798c; }

.principles { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.principles article, .protocol-grid > div { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.principles p { color: var(--muted); margin: 0; }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(24px, 5vw, 64px); align-items: start; }
.protocol-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.protocol-grid p { color: var(--muted); margin: 0; }
.check-list { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 8px; color: #c4ccda; }
.check-list li::before { content: "✓"; color: var(--ok); margin-right: 8px; }
.terminal { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.terminal-bar { display: flex; gap: 6px; padding: 10px 12px; border-bottom: 1px solid var(--line); }
.terminal-bar span { width: 9px; height: 9px; border-radius: 50%; background: #3c465c; }
.terminal pre { border: 0; border-radius: 0; background: transparent; }
.security .principles { margin-top: 20px; }
.closing { border-bottom: 0; text-align: center; }
.closing .cta-row { justify-content: center; }
footer { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding: 24px clamp(16px, 5vw, 64px); border-top: 1px solid var(--line); color: var(--muted); font-size: 0.85rem; }

@media (max-width: 820px) {
  .hero, .split { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .principles, .protocol-grid { grid-template-columns: 1fr; }
  .site-header { align-items: flex-start; flex-direction: column; }
  .graphic-slot { min-height: 240px; }
}