:root {
  --bg: #0d1117;
  --bg2: #161b22;
  --bg3: #21262d;
  --border: #30363d;
  --accent: #e62429;
  --accent2: #f5a623;
  --text: #e6edf3;
  --text2: #8b949e;
  --link: #58a6ff;
  --radius: 8px;
}

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

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

/* ── Header ── */
header {
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 20px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}
.logo-icon { font-size: 1.4rem; }
.logo-text {
  font-size: 1.1rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.search-wrap {
  flex: 1;
  max-width: 500px;
  position: relative;
}
#searchInput {
  width: 100%;
  padding: 8px 14px;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: 20px;
  color: var(--text);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.2s;
}
#searchInput:focus { border-color: var(--accent); }
.search-results {
  position: absolute;
  top: calc(100% + 6px);
  left: 0; right: 0;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(0,0,0,0.5);
  z-index: 200;
}
.search-results.hidden { display: none; }
.search-item {
  padding: 10px 14px;
  cursor: pointer;
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}
.search-item:last-child { border-bottom: none; }
.search-item:hover { background: var(--bg3); }
.search-item-title { font-weight: 600; font-size: 0.9rem; }
.search-item-tags { font-size: 0.75rem; color: var(--text2); margin-top: 2px; }

/* ── Layout ── */
.layout {
  max-width: 1600px;
  margin: 0 auto;
  display: flex;
  gap: 0;
  min-height: calc(100vh - 57px);
}

/* ── Chat Panel ── */
#chat-panel {
  width: 340px;
  flex-shrink: 0;
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 57px;
  height: calc(100vh - 57px);
  background: var(--bg2);
}
.chat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--bg3);
}
.chat-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
}
.chat-toggle-btn {
  background: none;
  border: none;
  color: var(--text2);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 2px 6px;
  border-radius: 4px;
  display: none;
}
.chat-toggle-btn:hover { color: var(--text); background: var(--border); }
.chat-context-bar {
  padding: 6px 14px;
  background: rgba(230, 36, 41, 0.08);
  border-bottom: 1px solid var(--border);
  font-size: 0.73rem;
  color: var(--accent);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.chat-msg { display: flex; }
.chat-msg.user { justify-content: flex-end; }
.chat-msg.assistant { justify-content: flex-start; }
.chat-bubble {
  max-width: 85%;
  padding: 10px 13px;
  border-radius: 14px;
  font-size: 0.84rem;
  line-height: 1.55;
  word-break: break-word;
  white-space: pre-wrap;
}
.chat-msg.user .chat-bubble {
  background: var(--accent);
  color: #fff;
  border-bottom-right-radius: 4px;
}
.chat-msg.assistant .chat-bubble {
  background: var(--bg3);
  color: var(--text);
  border-bottom-left-radius: 4px;
}
.chat-msg.assistant .chat-bubble.thinking {
  color: var(--text2);
  font-style: italic;
}
.chat-input-area {
  display: flex;
  gap: 8px;
  padding: 12px;
  border-top: 1px solid var(--border);
  background: var(--bg2);
}
#chatInput {
  flex: 1;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 0.83rem;
  padding: 8px 10px;
  resize: none;
  outline: none;
  font-family: inherit;
  line-height: 1.4;
}
#chatInput:focus { border-color: var(--accent); }
.chat-send-btn {
  background: var(--accent);
  border: none;
  color: #fff;
  font-weight: 700;
  font-size: 0.82rem;
  padding: 0 14px;
  border-radius: 8px;
  cursor: pointer;
  align-self: flex-end;
  height: 38px;
  transition: opacity 0.15s;
}
.chat-send-btn:hover { opacity: 0.85; }
.chat-send-btn:disabled { opacity: 0.5; cursor: default; }

/* ── Chat FAB (mobile) ── */
.chat-fab {
  display: none;
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  font-size: 1.4rem;
  cursor: pointer;
  z-index: 300;
  box-shadow: 0 4px 16px rgba(0,0,0,0.4);
}

/* ── Sidebar ── */
#sidebar {
  width: 240px;
  flex-shrink: 0;
  border-right: 1px solid var(--border);
  padding: 20px 0;
  position: sticky;
  top: 57px;
  height: calc(100vh - 57px);
  overflow-y: auto;
}
.sidebar-section { margin-bottom: 24px; }
.sidebar-section h3 {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text2);
  padding: 0 16px 8px;
}
.sidebar-section ul { list-style: none; }
.sidebar-section ul li a {
  display: block;
  padding: 6px 16px;
  font-size: 0.85rem;
  color: var(--text2);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: all 0.15s;
}
.sidebar-section ul li a:hover,
.sidebar-section ul li a.active {
  color: var(--text);
  border-left-color: var(--accent);
  background: rgba(230, 36, 41, 0.08);
}

/* ── Main Content ── */
#content {
  flex: 1;
  padding: 32px 40px;
  min-width: 0;
}

/* ── Hero ── */
.hero {
  text-align: center;
  padding: 40px 0 32px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 32px;
}
.hero h1 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 12px;
}
.hero p {
  color: var(--text2);
  font-size: 1rem;
  line-height: 1.7;
}

/* ── Card Grid ── */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 40px;
}
.category-card {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  cursor: pointer;
  transition: all 0.2s;
}
.category-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(230, 36, 41, 0.15);
}
.card-icon { font-size: 1.8rem; margin-bottom: 10px; }
.category-card h3 { font-size: 0.95rem; margin-bottom: 6px; }
.category-card p { font-size: 0.8rem; color: var(--text2); line-height: 1.5; }

/* ── Tag Cloud ── */
.tag-cloud-section h2 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text2);
}
.tag-cloud { display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  padding: 4px 12px;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.78rem;
  color: var(--text2);
  cursor: pointer;
  transition: all 0.15s;
}
.tag:hover {
  background: rgba(230, 36, 41, 0.12);
  border-color: var(--accent);
  color: var(--accent);
}

/* ── Doc View ── */
.hidden { display: none !important; }
.doc-toolbar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
#backBtn {
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: all 0.15s;
}
#backBtn:hover { border-color: var(--accent); color: var(--accent); }
.doc-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.doc-tag {
  padding: 3px 10px;
  background: rgba(230, 36, 41, 0.12);
  border: 1px solid rgba(230, 36, 41, 0.3);
  border-radius: 20px;
  font-size: 0.72rem;
  color: var(--accent);
  cursor: pointer;
}
.doc-tag:hover { background: rgba(230, 36, 41, 0.25); }

/* ── Markdown Article ── */
#docContent {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 36px;
  line-height: 1.8;
  max-width: 820px;
}
#docContent h1 {
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--accent);
}
#docContent h2 {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 28px 0 12px;
  color: var(--accent2);
}
#docContent h3 {
  font-size: 1rem;
  font-weight: 600;
  margin: 20px 0 8px;
}
#docContent p { margin-bottom: 12px; }
#docContent ul, #docContent ol {
  margin: 8px 0 12px 20px;
}
#docContent li { margin-bottom: 4px; }
#docContent table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 0.88rem;
}
#docContent th {
  background: var(--bg3);
  padding: 8px 12px;
  text-align: left;
  border: 1px solid var(--border);
  font-weight: 600;
}
#docContent td {
  padding: 8px 12px;
  border: 1px solid var(--border);
}
#docContent tr:nth-child(even) td { background: rgba(255,255,255,0.02); }
#docContent strong { color: var(--accent2); }
#docContent code {
  background: var(--bg3);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.85em;
  font-family: 'JetBrains Mono', monospace;
}
#docContent a { color: var(--link); }
#docContent blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 16px;
  color: var(--text2);
  margin: 12px 0;
}
#docContent input[type="checkbox"] { margin-right: 6px; }

/* ── Related Section ── */
.related-section {
  margin-top: 32px;
  max-width: 820px;
}
.related-section h3 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text2);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}
.related-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 10px;
}
.related-card {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  cursor: pointer;
  transition: all 0.15s;
  font-size: 0.82rem;
}
.related-card:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text2); }

/* ── Responsive ── */
@media (max-width: 1100px) {
  #chat-panel { display: none; }
  #chat-panel.open {
    display: flex;
    position: fixed;
    top: 57px; right: 0; bottom: 0;
    width: 320px;
    z-index: 250;
    box-shadow: -4px 0 20px rgba(0,0,0,0.5);
  }
  .chat-fab { display: flex; align-items: center; justify-content: center; }
  .chat-toggle-btn { display: block; }
}
@media (max-width: 768px) {
  #sidebar { display: none; }
  #content { padding: 20px 16px; }
  .hero h1 { font-size: 1.5rem; }
  #docContent { padding: 20px 16px; }
}