:root {
  --ink:       #0f172a;
  --ink-mid:   #334155;
  --ink-soft:  #64748b;
  --paper:     #f8fafc;
  --paper-mid: #ffffff;
  --accent:    #4f46e5;
  --accent-soft: #e0e7ff;
  --accent-2:  #b45309;
  --rule:      #e2e8f0;
  --hero-bg:   linear-gradient(135deg, #eef2ff 0%, #e0e7ff 45%, #f8fafc 100%);
  --serif: 'Libre Baskerville', Georgia, serif;
  --sans:  'IBM Plex Sans', system-ui, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.7;
  font-size: 16px;
  overflow-x: hidden;
}

header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.94);
  backdrop-filter: blur(10px);
  border-bottom: 2px solid var(--accent-soft);
  padding: 14px 40px;
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px;
}

.logo {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--ink);
}
.logo-mark {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--accent);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 15px; line-height: 1;
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.25);
}
.logo-text { font-size: 1.05rem; font-weight: 600; letter-spacing: -.01em; }

.header-right {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
}

.doc-badge {
  font-size: .72rem; font-weight: 600; letter-spacing: .06em;
  text-transform: uppercase; color: var(--accent);
  background: var(--accent-soft); border: 1px solid #c7d2fe;
  padding: 5px 14px; border-radius: 6px;
}

.lang-switch {
  display: inline-flex; align-items: center; gap: 4px;
  background: #f1f5f9; border: 1px solid var(--rule);
  border-radius: 999px; padding: 4px;
}
.lang-switch button {
  border: 0; background: transparent; color: var(--ink-soft);
  font: inherit; font-size: .78rem; font-weight: 600;
  padding: 6px 12px; border-radius: 999px; cursor: pointer;
}
.lang-switch button.active {
  background: #fff; color: var(--accent);
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.08);
}
.lang-switch button:hover:not(.active) { color: var(--ink-mid); }

.hero {
  padding: 64px 40px 48px; max-width: 820px; margin: 0 auto;
  background: var(--hero-bg); border-bottom: 1px solid var(--rule);
}
.hero-eyebrow {
  font-size: .72rem; font-weight: 600; letter-spacing: .14em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 14px;
}
.hero h1 {
  font-family: var(--serif);
  font-size: clamp(2rem, 4.5vw, 3rem);
  line-height: 1.15; letter-spacing: -.01em;
  color: var(--ink); margin-bottom: 18px; max-width: 24ch;
}
.hero h1 em { font-style: italic; color: var(--accent); }
.hero-meta {
  display: flex; gap: 12px; flex-wrap: wrap;
  font-size: .84rem; color: var(--ink-soft);
  padding-top: 18px; margin-top: 8px;
}
.hero-meta span {
  display: flex; align-items: center; gap: 6px;
  background: rgba(255,255,255,0.7);
  border: 1px solid var(--rule); border-radius: 999px;
  padding: 6px 14px;
}
.hero-meta strong { color: var(--ink-mid); }

.page-wrap { max-width: 820px; margin: 0 auto; padding: 48px 40px 100px; }

.quick-nav {
  background: var(--paper-mid); border: 1px solid var(--rule);
  border-radius: 14px; padding: 24px 28px; margin-bottom: 48px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.05);
}
.quick-nav-title {
  font-size: .7rem; font-weight: 700; letter-spacing: .12em;
  text-transform: uppercase; color: var(--ink-soft); margin-bottom: 14px;
}
.quick-nav ol { list-style: none; columns: 2; gap: 8px; }
.quick-nav li { margin-bottom: 6px; }
.quick-nav a {
  font-size: .9rem; color: var(--ink-mid); text-decoration: none;
  display: flex; align-items: center; gap: 6px;
}
.quick-nav a::before { content: '§'; font-size: .75rem; font-weight: 700; color: var(--accent); }
.quick-nav a:hover { color: var(--accent); }

.section { margin-bottom: 56px; }
.section-number {
  display: inline-flex; align-items: center; justify-content: center;
  width: 2rem; height: 2rem; border-radius: 50%;
  font-size: .72rem; font-weight: 700; color: var(--accent);
  background: var(--accent-soft); border: 1px solid #c7d2fe; margin-bottom: 12px;
}
.section h2 {
  font-size: 1.35rem; font-weight: 600; line-height: 1.25;
  margin-bottom: 18px; color: var(--ink);
  padding-bottom: 10px; border-bottom: 2px solid var(--accent-soft);
}
.section p { color: var(--ink-mid); margin-bottom: 16px; font-size: .95rem; }
.section ul, .section ol { margin: 12px 0 16px 0; padding-left: 0; list-style: none; }
.section ul li, .section ol li {
  position: relative; padding-left: 20px; margin-bottom: 10px;
  color: var(--ink-mid); font-size: .95rem;
}
.section ul li::before {
  content: ''; position: absolute; left: 2px; top: 10px;
  width: 6px; height: 6px; background: var(--accent); border-radius: 50%;
}
.section code {
  background: #f1f5f9; padding: 2px 6px; border-radius: 4px;
  font-size: 0.88em; word-break: break-word;
}
.section a { color: var(--accent); }

.callout {
  border: 1px solid #c7d2fe; border-left: 4px solid var(--accent);
  background: #eef2ff; border-radius: 10px; padding: 16px 20px; margin: 20px 0;
}
.callout p { margin: 0; font-size: .9rem; color: var(--ink-mid); }
.callout strong { color: var(--ink); }
.callout-warn { border-color: #fcd34d; border-left-color: var(--accent-2); background: #fffbeb; }

.contact-card {
  background: linear-gradient(135deg, #3730a3 0%, #4f46e5 100%);
  color: #eef2ff; border-radius: 14px; padding: 32px 36px; margin-top: 48px;
  box-shadow: 0 12px 40px rgba(79, 70, 229, 0.2);
}
.contact-card h3 { font-family: var(--serif); font-size: 1.35rem; margin-bottom: 10px; }
.contact-card p { color: rgba(238,242,255,.75); font-size: .9rem; margin-bottom: 20px; }
.contact-card a {
  display: inline-flex; align-items: center; gap: 8px;
  background: #fff; color: var(--accent); text-decoration: none;
  padding: 10px 20px; border-radius: 999px; font-weight: 600; font-size: .9rem;
}

.lang-note {
  font-size: .82rem; color: var(--ink-soft); margin-bottom: 24px;
  padding: 10px 14px; background: #fff; border: 1px solid var(--rule); border-radius: 8px;
}

footer {
  border-top: 1px solid var(--rule); background: #fff;
  padding: 24px 40px;
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 12px;
  font-size: .8rem; color: var(--ink-soft);
}
footer a { color: var(--accent); text-decoration: none; font-weight: 500; }

@media (max-width: 600px) {
  header, .hero, footer { padding-left: 20px; padding-right: 20px; }
  .page-wrap { padding: 0 20px 80px; }
  .quick-nav ol { columns: 1; }
  .doc-badge { display: none; }
}