:root {
  --color-primary: #FF6600;
  --color-primary-dark: #E55A00;
  --color-text: #1a1a2e;
  --color-text-light: #64748b;
  --color-bg: #ffffff;
  --color-bg-secondary: #f8fafc;
  --color-border: #e2e8f0;
  --color-success: #10b981;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

/* Layout */
.layout {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 280px;
  background: var(--color-bg-secondary);
  border-right: 1px solid var(--color-border);
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 24px 0;
}

.sidebar-header {
  padding: 0 24px 24px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 16px;
}

.logo {
  max-width: 180px;
  height: auto;
  margin-bottom: 8px;
}

.logo-text {
  font-size: 14px;
  color: var(--color-text-light);
  font-weight: 500;
}

.nav-section {
  padding: 8px 16px;
}

.nav-section-title {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-light);
  padding: 8px;
  margin-bottom: 4px;
}

.nav-link {
  display: block;
  padding: 8px 16px;
  color: var(--color-text);
  text-decoration: none;
  border-radius: 6px;
  font-size: 14px;
  transition: all 0.15s ease;
}

.nav-link:hover {
  background: rgba(0,0,0,0.05);
  color: var(--color-primary);
}

.nav-link.active {
  background: var(--color-primary);
  color: white;
}

/* Main content */
.main-content {
  flex: 1;
  margin-left: 280px;
  min-width: 0;
}

/* Header */
.header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: 16px 32px;
  position: sticky;
  top: 0;
  z-index: 100;
}

.search-container {
  max-width: 400px;
}

.search-input {
  width: 100%;
  padding: 10px 16px;
  font-size: 14px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-bg-secondary);
  outline: none;
  transition: all 0.15s ease;
}

.search-input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(255, 102, 0, 0.1);
}

.search-results {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: white;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  margin-top: 4px;
  max-height: 400px;
  overflow-y: auto;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  display: none;
}

.search-results.active {
  display: block;
}

.search-result-item {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
  cursor: pointer;
  transition: background 0.15s ease;
}

.search-result-item:hover {
  background: var(--color-bg-secondary);
}

.search-result-item:last-child {
  border-bottom: none;
}

.search-result-title {
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 4px;
}

.search-result-category {
  font-size: 12px;
  color: var(--color-text-light);
}

/* Content area */
.content {
  padding: 32px;
  max-width: 800px;
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-light);
  margin-bottom: 24px;
}

.breadcrumbs a {
  color: var(--color-text-light);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--color-primary);
}

.breadcrumbs span {
  color: var(--color-text-light);
}

/* Article styles */
.article-header {
  margin-bottom: 32px;
}

.article-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 8px;
  line-height: 1.2;
}

.article-meta {
  font-size: 14px;
  color: var(--color-text-light);
}

.article-summary {
  font-size: 18px;
  color: var(--color-text-light);
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.article-content h2 {
  font-size: 24px;
  font-weight: 600;
  margin-top: 40px;
  margin-bottom: 16px;
  color: var(--color-text);
}

.article-content h3 {
  font-size: 18px;
  font-weight: 600;
  margin-top: 32px;
  margin-bottom: 12px;
  color: var(--color-text);
}

.article-content p {
  margin-bottom: 16px;
}

.article-content ul,
.article-content ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content strong {
  font-weight: 600;
}

.article-content code {
  font-family: var(--font-mono);
  background: var(--color-bg-secondary);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 14px;
}

.article-content a {
  color: var(--color-primary);
  text-decoration: none;
}

.article-content a:hover {
  text-decoration: underline;
}

/* Info boxes */
.info-box {
  padding: 16px 20px;
  border-radius: 8px;
  margin: 24px 0;
}

.info-box.tip {
  background: #ecfdf5;
  border-left: 4px solid var(--color-success);
}

.info-box.warning {
  background: #fffbeb;
  border-left: 4px solid #f59e0b;
}

.info-box.note {
  background: #f0f9ff;
  border-left: 4px solid #0ea5e9;
}

/* Home page */
.home-hero {
  text-align: center;
  padding: 48px 32px;
  background: linear-gradient(135deg, #fff8f3 0%, #fff 100%);
  margin: -32px -32px 32px;
}

.home-title {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 16px;
}

.home-subtitle {
  font-size: 18px;
  color: var(--color-text-light);
  max-width: 600px;
  margin: 0 auto 32px;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
  padding: 32px 0;
}

.category-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 24px;
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.2s ease;
}

.category-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(255, 102, 0, 0.1);
  transform: translateY(-2px);
}

.category-card-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.category-card-desc {
  font-size: 14px;
  color: var(--color-text-light);
}

.category-card-count {
  font-size: 12px;
  color: var(--color-primary);
  margin-top: 12px;
}

/* Related articles */
.related-articles {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
}

.related-articles h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 16px;
}

.related-articles ul {
  list-style: none;
  padding: 0;
}

.related-articles li {
  margin-bottom: 8px;
}

.related-articles a {
  color: var(--color-primary);
  text-decoration: none;
}

.related-articles a:hover {
  text-decoration: underline;
}

/* Footer */
.footer {
  text-align: center;
  padding: 32px;
  color: var(--color-text-light);
  font-size: 14px;
  border-top: 1px solid var(--color-border);
  margin-top: 48px;
}

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    z-index: 1000;
  }
  
  .sidebar.open {
    transform: translateX(0);
  }
  
  .main-content {
    margin-left: 0;
  }
  
  .content {
    padding: 16px;
  }
  
  .home-hero {
    padding: 32px 16px;
    margin: -16px -16px 16px;
  }
  
  .article-title {
    font-size: 24px;
  }
}