:root {
  --primary: #1a2a3a;
  --accent: #c76919;
  --accent-light: #f0a050;
  --bg: #ffffff;
  --bg-alt: #f7f7f7;
  --bg-dark: #1a2a3a;
  --border: #cccccc;
  --danger: #c0392b;
  --success: #1a6b35;
  --note: #1a5276;
  --text: #222222;
  --text-light: #555555;
  --radius: 4px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Segoe UI', Arial, sans-serif;
  font-size: 15px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

.cover {
  background: var(--bg-dark);
  color: #fff;
  text-align: center;
  padding: 60px 40px 50px;
}
.cover .org { font-size: 13px; letter-spacing: 3px; text-transform: uppercase; color: var(--accent-light); margin-bottom: 18px; }
.cover h1 { font-size: 2.4rem; font-weight: 700; line-height: 1.2; margin-bottom: 14px; }
.cover .subtitle { font-size: 1.1rem; color: #b0bfc8; margin-bottom: 30px; }
.cover .meta { font-size: 12px; color: #8a9aaa; letter-spacing: 1px; }

.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }

.language-switch {
  background: var(--bg-alt);
  border-bottom: 1px solid var(--border);
  padding: 14px 24px;
}
.language-switch .container {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}
.language-label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-light);
}
.language-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.language-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: #fff;
  color: var(--primary);
  text-decoration: none;
  font-size: 13px;
  transition: border-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}
.language-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}
.language-link.current {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.toc {
  background: var(--bg-alt);
  border-left: 4px solid var(--accent);
  padding: 28px 32px;
  margin: 40px 0;
  border-radius: var(--radius);
}
.toc h2 { font-size: 1rem; text-transform: uppercase; letter-spacing: 1px; color: var(--accent); margin-bottom: 16px; }
.toc ol { margin-left: 18px; }
.toc li { margin: 4px 0; }
.toc a { color: var(--primary); text-decoration: none; }
.toc a:hover { color: var(--accent); text-decoration: underline; }

.section { padding: 44px 0; border-bottom: 1px solid var(--border); }
.section:last-child { border-bottom: none; }

h2.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  border-bottom: 3px solid var(--accent);
  padding-bottom: 8px;
  margin-bottom: 24px;
}
.section-num {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 2px;
  margin-right: 8px;
  vertical-align: middle;
}

h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary);
  margin: 28px 0 10px;
  padding-left: 10px;
  border-left: 3px solid var(--accent);
}
h4 {
  font-size: 0.95rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-light);
  margin: 20px 0 8px;
}

p { margin-bottom: 12px; }
ul, ol { margin: 10px 0 12px 22px; }
li { margin-bottom: 5px; }

.rule-block {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 14px 0;
}
.rule-block.info { border-left: 4px solid var(--note); }
.rule-block.warning { border-left: 4px solid var(--danger); }
.rule-block.gap { border-left: 4px solid #aaa; }

.disc-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; margin: 20px 0; }
.disc-card { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.disc-card-head { background: var(--primary); color: #fff; padding: 12px 16px; font-weight: 700; font-size: 0.9rem; }
.disc-card-body { padding: 14px 16px; font-size: 0.88rem; }
.disc-card-body dl { display: grid; grid-template-columns: auto 1fr; gap: 4px 12px; }
.disc-card-body dt { font-weight: 700; color: var(--text-light); white-space: nowrap; }
.disc-card-body dd { margin: 0; }

.sector-diagram { margin: 20px 0; overflow-x: auto; }
.sector-table { border-collapse: collapse; width: 100%; min-width: 560px; font-size: 13px; }
.sector-table th, .sector-table td { border: 1px solid var(--border); padding: 7px 10px; text-align: center; }
.sector-table thead th { background: var(--primary); color: #fff; }
.sector-table tbody tr:nth-child(even) { background: var(--bg-alt); }
.sector-table .start-col { background: #e8f5e9; font-weight: 700; }

.step-list { counter-reset: step; margin: 16px 0; }
.step-list li {
  list-style: none;
  position: relative;
  padding-left: 44px;
  margin-bottom: 14px;
  counter-increment: step;
}
.step-list li::before {
  content: counter(step);
  position: absolute;
  left: 0; top: 0;
  width: 28px; height: 28px;
  background: var(--accent);
  color: #fff;
  border-radius: 50%;
  text-align: center;
  line-height: 28px;
  font-weight: 700;
  font-size: 13px;
}

.example-grid { display: grid; gap: 20px; margin: 20px 0; }
.example { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.example-head { background: var(--primary); color: #fff; padding: 10px 16px; font-size: 0.85rem; font-weight: 700; }
.example-body { padding: 14px 16px; font-size: 0.9rem; }
.example-body .scenario { background: #eef4fb; border-radius: 3px; padding: 8px 12px; margin-bottom: 10px; font-style: italic; }
.example-body .ruling { background: #eafaf1; border-radius: 3px; padding: 8px 12px; border-left: 3px solid var(--success); }
.example-body .ruling.invalid { background: #fdf2f2; border-left-color: var(--danger); }
.example-body .ruling strong { color: var(--success); }
.example-body .ruling.invalid strong { color: var(--danger); }

.edge-case { margin: 18px 0; padding: 16px 20px; background: var(--bg-alt); border-radius: var(--radius); border: 1px solid var(--border); }
.edge-case-q { font-weight: 700; color: var(--primary); margin-bottom: 8px; }
.edge-case-a { margin-bottom: 0; }

.def-list dt { font-weight: 700; color: var(--primary); margin-top: 14px; }
.def-list dd { margin-left: 16px; margin-top: 2px; }

footer {
  background: var(--bg-dark);
  color: #8a9aaa;
  text-align: center;
  padding: 30px 24px;
  font-size: 12px;
  margin-top: 60px;
}

@media print {
  .cover { padding: 30px 20px; }
  .section { padding: 24px 0; }
  h2.section-title { page-break-after: avoid; }
  .example, .edge-case { page-break-inside: avoid; }
}

@media (max-width: 600px) {
  .cover h1 { font-size: 1.6rem; }
  .disc-cards { grid-template-columns: 1fr; }
}