:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface-hover: #242836;
  --surface-raised: #252a3a;
  --border: #2d3148;
  --border-inner: #1f2333;
  --border-hover: #3d4466;
  --text: #e1e4ed;
  --text-muted: #8b90a5;
  --accent: #ff8c42;
  --accent-hover: #ffaa6e;
  --construction: #ff8c42;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  color: var(--accent-hover);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2rem;
}

footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  font-size: 0.8rem;
  border-top: 1px solid var(--border);
  margin-top: 3rem;
}

@media (max-width: 600px) {
  .container {
    padding: 1rem;
  }
}
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 1rem 2rem;
  position: sticky;
  top: 0;
  z-index: 100;
}
.site-header .header-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.site-header .site-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
}
.site-header nav a {
  margin-left: 1.5rem;
  font-size: 0.9rem;
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  transition: background 0.2s;
}
.site-header nav a:hover {
  background: var(--surface-hover);
}
.site-header nav a.units {
  color: var(--construction);
}
.site-header nav a.glossary {
  color: var(--accent);
}

@media (max-width: 600px) {
  .site-header {
    padding: 0.8rem 1rem;
  }
  .site-header .header-inner {
    flex-wrap: wrap;
  }
  .site-header nav a {
    margin-left: 0.8rem;
    font-size: 0.8rem;
  }
}
.hero {
  text-align: center;
  padding: 3rem 0;
}
.hero h1 {
  font-size: 2.4rem;
  margin-bottom: 0.5rem;
  color: var(--accent);
}
.hero p {
  color: var(--text-muted);
  font-size: 1.1rem;
}

.units-home {
  margin-top: 2rem;
}

.unit-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}
.unit-card h2 {
  font-size: 1.2rem;
  margin-bottom: 0.3rem;
}
.unit-card .unit-desc {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}
.unit-card .topic-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 0.5rem;
}
.unit-card .topic-list li a {
  display: block;
  padding: 0.5rem 0.8rem;
  background: var(--bg);
  border-radius: 6px;
  font-size: 0.9rem;
}
.unit-card .topic-list li a:hover {
  background: var(--surface-hover);
}

@media (max-width: 600px) {
  .hero h1 {
    font-size: 1.6rem;
  }
}
.breadcrumb {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}
.breadcrumb a {
  color: var(--text-muted);
}
.breadcrumb a:hover {
  color: var(--accent);
}
.breadcrumb .sep {
  margin: 0 0.4rem;
}

.unit-header {
  margin-bottom: 2rem;
}
.unit-header h1 {
  font-size: 1.8rem;
}
.unit-header p {
  color: var(--text-muted);
  margin-top: 0.3rem;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1rem;
}

.topic-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.2rem;
  transition: transform 0.2s, border-color 0.2s;
}
.topic-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
}
.topic-card h3 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.topic-page .topic-header {
  margin-bottom: 2rem;
}
.topic-page .topic-header h1 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent);
}
.topic-page .topic-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 2rem;
}
.topic-page .toc {
  min-width: 0;
}
.topic-page .toc .toc-sticky {
  position: sticky;
  top: 5rem;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem;
}
.topic-page .toc .toc-sticky::-webkit-scrollbar {
  width: 4px;
}
.topic-page .toc .toc-sticky::-webkit-scrollbar-track {
  background: transparent;
}
.topic-page .toc .toc-sticky::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}
.topic-page .toc .toc-toggle {
  display: none;
}
.topic-page .toc .toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.topic-page .toc .toc-list li {
  margin-bottom: 0.15rem;
}
.topic-page .toc .toc-list a {
  display: block;
  padding: 0.35rem 0.6rem;
  font-size: 0.78rem;
  color: var(--text-muted);
  border-radius: 6px;
  border-left: 2px solid transparent;
  transition: all 0.15s;
  line-height: 1.35;
}
.topic-page .toc .toc-list a:hover {
  color: var(--text);
  background: var(--surface-hover);
}
.topic-page .toc .toc-list a.active {
  color: var(--accent);
  background: rgba(255, 140, 66, 0.08);
  border-left-color: var(--accent);
  font-weight: 600;
}
@media (max-width: 860px) {
  .topic-page .topic-layout {
    display: block;
  }
  .topic-page .toc {
    margin-bottom: 1.5rem;
  }
  .topic-page .toc .toc-sticky {
    position: relative;
    top: 0;
    max-height: none;
    padding: 0;
    overflow: visible;
  }
  .topic-page .toc .toc-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text);
  }
  .topic-page .toc .toc-toggle svg {
    transition: transform 0.2s;
  }
  .topic-page .toc .toc-list {
    display: none;
    padding: 0 0.5rem 0.75rem;
  }
  .topic-page .toc .toc-list.open {
    display: block;
  }
  .topic-page .toc:has(.toc-list.open) .toc-toggle svg {
    transform: rotate(180deg);
  }
}
.topic-page .section-nav {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.2rem 1.5rem;
  margin-bottom: 1.5rem;
}
.topic-page .section-nav h2 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 0.8rem;
}
.topic-page .section-nav ol {
  margin: 0;
  padding-left: 1.2rem;
}
.topic-page .section-nav ol li {
  padding: 0.35rem 0;
  font-size: 0.9rem;
  color: var(--text);
  border-bottom: 1px solid var(--border);
}
.topic-page .section-nav ol li:last-child {
  border-bottom: none;
}
.topic-page .content-placeholder {
  background: var(--surface);
  border: 2px dashed var(--border);
  border-radius: 12px;
  padding: 3rem;
  text-align: center;
  margin-top: 2rem;
  color: var(--text-muted);
}
.topic-page .content-placeholder h2 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--text);
}
.topic-page .topic-content {
  margin-top: 2rem;
}
.topic-page .topic-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--accent);
  color: var(--accent);
}
.topic-page .topic-content h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 1.8rem;
  margin-bottom: 0.6rem;
  color: var(--text);
  padding-left: 0.6rem;
  border-left: 3px solid var(--accent);
}
.topic-page .topic-content h4 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-top: 1.2rem;
  margin-bottom: 0.4rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.topic-page .topic-content p {
  margin-bottom: 0.8rem;
  color: var(--text);
  line-height: 1.7;
}
.topic-page .topic-content ul, .topic-page .topic-content ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}
.topic-page .topic-content ul li, .topic-page .topic-content ol li {
  margin-bottom: 0.3rem;
  line-height: 1.6;
}
.topic-page .topic-content .table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 1.2rem 0 1.8rem;
  border-radius: 12px;
  border: 2px solid var(--border-hover);
  background: var(--bg);
}
.topic-page .topic-content table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-size: 0.88rem;
  margin: 0;
}
.topic-page .topic-content table th {
  background: var(--surface-raised);
  font-weight: 700;
  color: var(--text);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 2px solid var(--accent);
  position: sticky;
  top: 0;
}
.topic-page .topic-content table td {
  padding: 0.7rem 1rem;
  text-align: left;
  vertical-align: top;
  color: var(--text);
  background: transparent;
  border-bottom: 1px solid var(--border-inner);
}
.topic-page .topic-content table tr:nth-child(odd) td {
  background: rgba(255, 255, 255, 0.02);
}
.topic-page .topic-content table tr:nth-child(even) td {
  background: rgba(255, 140, 66, 0.03);
}
.topic-page .topic-content table tr:hover td {
  background: rgba(255, 140, 66, 0.08);
}
.topic-page .topic-content table tr:last-child td {
  border-bottom: none;
}
.topic-page .topic-content table td:first-child {
  font-weight: 600;
  color: var(--accent);
}
.topic-page .topic-content table td strong {
  color: var(--accent);
}
.topic-page .topic-content code {
  background: var(--surface);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.85em;
  color: var(--accent);
}
.topic-page .topic-content pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem;
  overflow-x: auto;
  margin: 1rem 0;
}
.topic-page .topic-content pre code {
  background: none;
  padding: 0;
  color: var(--text);
}
.topic-page .topic-content blockquote {
  border-left: 3px solid var(--accent);
  margin: 1rem 0;
  padding: 0.5rem 1rem;
  background: rgba(255, 140, 66, 0.05);
  border-radius: 0 8px 8px 0;
}
.topic-page .topic-content blockquote p {
  color: var(--text-muted);
  margin-bottom: 0;
}
.topic-page .topic-content .key-term {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.2rem;
  margin: 0.8rem 0;
}
.topic-page .topic-content .key-term strong {
  color: var(--accent);
}
.topic-page .topic-content .exam-tip {
  background: rgba(255, 140, 66, 0.08);
  border: 1px solid rgba(255, 140, 66, 0.25);
  border-radius: 10px;
  padding: 1rem 1.2rem;
  margin: 1.2rem 0;
}
.topic-page .topic-content .exam-tip::before {
  content: "Exam Tip";
  display: block;
  font-weight: 700;
  font-size: 0.8rem;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.4rem;
}
.topic-page .topic-content .exam-tip p {
  margin-bottom: 0;
  color: var(--text);
}
.topic-page .nav-links {
  display: flex;
  justify-content: space-between;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.topic-page .nav-links a {
  padding: 0.5rem 1rem;
  background: var(--surface);
  border-radius: 8px;
  font-size: 0.9rem;
}
.topic-page .nav-links a:hover {
  background: var(--surface-hover);
}

/*# sourceMappingURL=style.css.map */