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

:root {
  --primary: #0066cc;
  --primary-dark: #0052a3;
  --bg: #ffffff;
  --bg-light: #f8f9fa;
  --bg-lighter: #f0f2f5;
  --text: #24292e;
  --text-light: #586069;
  --border: #e1e4e8;
  --sidebar-bg: #fafbfc;
  --sidebar-width: 280px;
  --main-max-width: 800px;
}

html, body {
  height: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 15px;
}

.gitbook-container {
  display: flex;
  height: 100vh;
}

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

.sidebar-content {
  padding: 20px 0;
}

.sidebar-header {
  padding: 0 20px 20px;
  border-bottom: 1px solid var(--border);
}

.sidebar-header h1 {
  font-size: 18px;
  font-weight: 600;
}

.sidebar-header a {
  color: var(--text);
  text-decoration: none;
}

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

.sidebar-nav {
  margin-top: 10px;
}

.nav-section {
  margin-bottom: 5px;
}

.nav-section-title {
  padding: 12px 20px 8px;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--text-light);
  letter-spacing: 0.5px;
}

.nav-list {
  list-style: none;
}

.nav-list li {
  margin: 0;
}

.nav-link {
  display: block;
  padding: 8px 20px;
  color: var(--text-light);
  text-decoration: none;
  font-size: 13px;
  border-left: 3px solid transparent;
  transition: all 0.2s ease;
}

.nav-link:hover {
  color: var(--primary);
  background: var(--bg-lighter);
}

.nav-link.active {
  color: var(--primary);
  border-left-color: var(--primary);
  background: var(--bg-lighter);
  font-weight: 500;
}

/* MAIN CONTENT */
.main-content {
  margin-left: var(--sidebar-width);
  flex: 1;
  overflow-y: auto;
  background: var(--bg);
}

.page {
  max-width: var(--main-max-width);
  margin: 0 auto;
  padding: 40px 60px;
}

.page-header {
  margin-bottom: 40px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 20px;
}

.page-header h1 {
  font-size: 32px;
  font-weight: 600;
  margin-bottom: 10px;
  line-height: 1.2;
}

.page-meta {
  font-size: 13px;
  color: var(--text-light);
  margin: 0;
}

.page-content {
  line-height: 1.8;
  color: var(--text);
}

.page-content h1 {
  font-size: 28px;
  font-weight: 600;
  margin: 32px 0 16px;
  line-height: 1.3;
}

.page-content h2 {
  font-size: 22px;
  font-weight: 600;
  margin: 24px 0 12px;
  line-height: 1.3;
  border-bottom: 1px solid var(--border);
  padding-bottom: 8px;
}

.page-content h3 {
  font-size: 18px;
  font-weight: 600;
  margin: 20px 0 10px;
}

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

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

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

.page-content a {
  color: var(--primary);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: all 0.2s ease;
}

.page-content a:hover {
  border-bottom-color: var(--primary);
}

.page-content code {
  background: var(--bg-light);
  padding: 2px 6px;
  border-radius: 3px;
  font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
  font-size: 13px;
  color: #d73a49;
}

.page-content pre {
  background: var(--bg-light);
  padding: 16px;
  border-radius: 6px;
  overflow-x: auto;
  margin-bottom: 16px;
  border: 1px solid var(--border);
}

.page-content pre code {
  background: none;
  padding: 0;
  color: var(--text);
}

.page-content blockquote {
  padding: 12px 16px;
  margin: 16px 0;
  background: var(--bg-lighter);
  border-left: 4px solid var(--border);
  font-style: italic;
}

.page-content img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  margin: 20px 0;
  border: 1px solid var(--border);
}

/* NAVIGATION */
.page-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.nav-prev, .nav-next {
  color: var(--primary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.nav-prev:hover, .nav-next:hover {
  background: var(--bg-light);
}

.nav-next {
  margin-left: auto;
}

.pages-list {
  margin-top: 40px;
}

.pages-list h2 {
  margin-bottom: 16px;
}

.pages-list ul {
  list-style: none;
  margin-left: 0;
}

.pages-list li {
  margin-bottom: 16px;
}

.pages-list a {
  display: block;
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
  margin-bottom: 4px;
}

.pages-list a:hover {
  text-decoration: underline;
}

.pages-list p {
  color: var(--text-light);
  font-size: 13px;
  margin: 4px 0 0;
}

/* RESPONSIVE */
@media (max-width: 768px) {
  :root {
    --sidebar-width: 0;
  }

  .sidebar {
    position: fixed;
    left: -280px;
    width: 280px;
    z-index: 100;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  }

  .main-content {
    margin-left: 0;
  }

  .page {
    padding: 20px;
  }
}