:root {
  --page: #f7f6f2;
  --surface: #ffffff;
  --text: #20262d;
  --muted: #5f6873;
  --line: #d9d9d3;
  --soft: #eeeee9;
  --accent: #315fc8;
  --accent-strong: #24499b;
  --accent-soft: #e8eefc;
  --max: 1160px;
  --reading: 760px;
  --radius: 14px;
  --shadow: 0 14px 40px rgba(32, 38, 45, 0.07);
}
.theme-vpn { --accent: #087f74; --accent-strong: #07675f; --accent-soft: #e1f2ef; }
* { box-sizing: border-box; }
html { color-scheme: light; scroll-behavior: smooth; }
body { margin: 0; background: var(--page); color: var(--text); font-family: "Source Sans 3", "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif; font-size: 18px; line-height: 1.62; text-rendering: optimizeLegibility; }
a { color: var(--accent-strong); text-decoration-thickness: 1px; text-underline-offset: .18em; }
a:hover { color: var(--accent); }
img, svg { max-width: 100%; }
code, .mono, .eyebrow, .status, .language-badge { font-family: "IBM Plex Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.shell { width: min(calc(100% - 40px), var(--max)); margin-inline: auto; }
.reading-shell { width: min(calc(100% - 40px), var(--reading)); margin-inline: auto; }
.skip-link { position: fixed; left: 16px; top: -80px; z-index: 100; padding: 10px 14px; background: var(--text); color: #fff; border-radius: 8px; }
.skip-link:focus { top: 16px; }
.site-header { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid rgba(217,217,211,.9); background: rgba(247,246,242,.94); backdrop-filter: blur(12px); }
.header-inner { min-height: 72px; display: flex; align-items: center; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--text); font-weight: 720; text-decoration: none; letter-spacing: -.02em; white-space: nowrap; }
.brand-mark { color: var(--accent); font-family: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace; font-weight: 700; }
.desktop-nav { display: flex; align-items: center; gap: 22px; margin-left: auto; }
.desktop-nav a { color: var(--muted); font-size: .93rem; font-weight: 650; text-decoration: none; }
.desktop-nav a[aria-current="page"], .desktop-nav a:hover { color: var(--text); }
.header-tools { display: flex; align-items: center; gap: 12px; }
.language-badge { display: inline-flex; align-items: center; justify-content: center; min-width: 36px; min-height: 30px; border: 1px solid var(--line); border-radius: 8px; color: var(--muted); background: var(--surface); font-size: .76rem; font-weight: 700; }
.mobile-menu { display: none; position: relative; }
.mobile-menu summary { cursor: pointer; list-style: none; border: 1px solid var(--line); border-radius: 8px; padding: 5px 10px; background: var(--surface); color: var(--text); font-size: .88rem; font-weight: 700; }
.mobile-menu summary::-webkit-details-marker { display: none; }
.mobile-menu nav { position: absolute; right: 0; top: 44px; display: grid; min-width: 230px; padding: 10px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); box-shadow: var(--shadow); }
.mobile-menu nav a { padding: 9px 10px; border-radius: 7px; color: var(--text); text-decoration: none; font-weight: 650; }
.mobile-menu nav a:hover { background: var(--soft); }
.hero { padding: 104px 0 72px; border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; grid-template-columns: minmax(0,1.35fr) minmax(280px,.65fr); align-items: center; gap: 72px; }
.eyebrow { margin: 0 0 16px; color: var(--accent-strong); font-size: .76rem; font-weight: 760; letter-spacing: .11em; text-transform: uppercase; }
h1,h2,h3 { margin-top: 0; line-height: 1.13; letter-spacing: -.035em; }
h1 { max-width: 900px; margin-bottom: 22px; font-size: clamp(2.6rem,7vw,5.35rem); font-weight: 760; }
h2 { margin-bottom: 18px; font-size: clamp(1.8rem,4vw,3rem); font-weight: 730; }
h3 { margin-bottom: 10px; font-size: 1.3rem; font-weight: 720; }
.lead { max-width: 760px; margin: 0; color: var(--muted); font-size: clamp(1.12rem,2vw,1.34rem); }
.hero-actions,.button-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 10px 17px; border: 1px solid var(--accent); border-radius: 9px; background: var(--accent); color: #fff; font-weight: 720; text-decoration: none; }
.button:hover { background: var(--accent-strong); color: #fff; }
.button.secondary { border-color: var(--line); background: transparent; color: var(--text); }
.button.secondary:hover { border-color: var(--accent); color: var(--accent-strong); }
.diagram { padding: 26px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.diagram-row { display: flex; align-items: center; justify-content: space-between; gap: 10px; color: var(--muted); font-family: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace; font-size: .88rem; }
.diagram-node { flex: 1; padding: 12px 10px; border: 1px solid var(--line); border-radius: 9px; background: var(--page); color: var(--text); text-align: center; }
.diagram-arrow { color: var(--accent); font-weight: 800; }
.diagram-note { margin: 18px 0 0; color: var(--muted); font-size: .88rem; }
.section { padding: 78px 0; border-bottom: 1px solid var(--line); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-bottom: 30px; }
.section-heading p { max-width: 640px; margin: 0; color: var(--muted); }
.grid { display: grid; gap: 18px; }
.grid.two { grid-template-columns: repeat(2,minmax(0,1fr)); }
.grid.three { grid-template-columns: repeat(3,minmax(0,1fr)); }
.card { padding: 26px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.card.featured { box-shadow: var(--shadow); }
.card p:last-child { margin-bottom: 0; }
.card-copy { color: var(--muted); }
.card-link { display: inline-flex; margin-top: 12px; font-weight: 720; }
.status { display: inline-flex; margin-bottom: 16px; padding: 4px 8px; border-radius: 6px; background: var(--accent-soft); color: var(--accent-strong); font-size: .72rem; font-weight: 760; letter-spacing: .05em; text-transform: uppercase; }
.principle { padding-left: 18px; border-left: 3px solid var(--accent); }
.prose { padding: 72px 0 88px; }
.prose-header { margin-bottom: 44px; padding-bottom: 34px; border-bottom: 1px solid var(--line); }
.prose h1 { font-size: clamp(2.3rem,6vw,4.5rem); }
.prose h2 { margin-top: 2.2em; font-size: clamp(1.55rem,3vw,2.2rem); }
.prose h3 { margin-top: 1.8em; }
.prose p,.prose ul,.prose ol { max-width: 72ch; }
.prose li+li { margin-top: .45em; }
.prose-note { margin: 28px 0; padding: 20px 22px; border-left: 4px solid var(--accent); background: var(--accent-soft); }
.contact-box { margin-top: 34px; padding: 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.location-list { display: flex; flex-wrap: wrap; gap: 10px; padding: 0; list-style: none; }
.location-list li { padding: 6px 10px; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); color: var(--muted); font-size: .9rem; }
.site-footer { padding: 52px 0 34px; background: #20262d; color: #d8dde3; }
.footer-grid { display: grid; grid-template-columns: 1.5fr repeat(3,1fr); gap: 34px; }
.footer-brand { color: #fff; font-weight: 760; font-size: 1.12rem; }
.footer-copy { max-width: 34ch; color: #aeb6c0; font-size: .9rem; }
.footer-heading { margin: 0 0 12px; color: #fff; font-size: .82rem; font-weight: 760; letter-spacing: .08em; text-transform: uppercase; }
.footer-links { display: grid; gap: 8px; }
.footer-links a { color: #c9d0d8; font-size: .9rem; text-decoration: none; }
.footer-links a:hover { color: #fff; }
.footer-bottom { display: flex; justify-content: space-between; gap: 20px; margin-top: 42px; padding-top: 22px; border-top: 1px solid #3a414a; color: #98a2ae; font-size: .82rem; }
@media (max-width:860px) { .desktop-nav{display:none}.mobile-menu{display:block}.header-inner{gap:14px}.header-tools{margin-left:auto}.hero{padding-top:72px}.hero-grid,.grid.two,.grid.three,.footer-grid{grid-template-columns:1fr}.hero-grid{gap:38px}.footer-grid{gap:26px} }
@media (max-width:560px) { body{font-size:17px}.shell,.reading-shell{width:min(calc(100% - 28px),var(--max))}.site-header{position:static}.header-inner{min-height:64px}.brand-mark,.language-badge{display:none}.hero{padding:58px 0 54px}h1{font-size:2.55rem}.section,.prose{padding:58px 0}.section-heading,.footer-bottom{align-items:flex-start;flex-direction:column}.diagram{padding:18px}.diagram-row{align-items:stretch;flex-direction:column}.diagram-arrow{transform:rotate(90deg);text-align:center} }