:root {
  --primary: #4F46E5;
  --primary-hover: #4338CA;
  --bg-color: #0F172A;
  --surface: #1E293B;
  --surface-hover: #334155;
  --text-primary: #F8FAFC;
  --text-secondary: #94A3B8;
  --border-color: #334155;
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --font-family: 'Inter', system-ui, sans-serif;
  --glass: rgba(30, 41, 59, 0.7);
}

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  text-decoration: underline;
  color: #818CF8;
}

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

/* Sidebar */
.sidebar {
  width: 280px;
  background-color: var(--surface);
  border-right: 1px solid var(--border-color);
  padding: 2rem 1.5rem;
  position: fixed;
  height: 100vh;
  overflow-y: auto;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.sidebar h2 {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  color: #fff;
  font-weight: 700;
  letter-spacing: -0.025em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

.nav-links li {
  margin-bottom: 0.5rem;
}

.nav-links a {
  display: block;
  padding: 0.75rem 1rem;
  border-radius: 0.5rem;
  color: var(--text-secondary);
  font-weight: 500;
  transition: all 0.2s ease;
}

.nav-links a:hover, .nav-links a.active {
  background-color: var(--surface-hover);
  color: var(--text-primary);
  text-decoration: none;
  transform: translateX(4px);
}

/* Main Content */
.main-content {
  flex: 1;
  margin-left: 280px;
  padding: 3rem 4rem;
  max-width: 1000px;
}

.page-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: #fff;
  letter-spacing: -0.025em;
}

.content-body h1, 
.content-body h2, 
.content-body h3 {
  color: #fff;
  margin-top: 2rem;
  margin-bottom: 1rem;
  font-weight: 700;
}

.content-body h2 {
  font-size: 1.8rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
}

.content-body h3 {
  font-size: 1.4rem;
}

.content-body p, 
.content-body ul, 
.content-body ol {
  margin-bottom: 1.25rem;
  color: var(--text-secondary);
}

.content-body ul, 
.content-body ol {
  padding-left: 1.5rem;
}

.content-body li {
  margin-bottom: 0.5rem;
}

.content-body strong {
  color: var(--text-primary);
}

.content-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  background-color: var(--surface);
  border-radius: 0.5rem;
  overflow: hidden;
}

.content-body th, 
.content-body td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.content-body th {
  background-color: rgba(255, 255, 255, 0.05);
  font-weight: 600;
  color: #fff;
}

.content-body tr:last-child td {
  border-bottom: none;
}

/* Interactive Cards / Checklist */
.checklist-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
  background-color: rgba(255, 255, 255, 0.03);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  margin-bottom: 0.5rem;
  transition: all 0.2s ease;
  cursor: pointer;
}

.checklist-item:hover {
  background-color: rgba(255, 255, 255, 0.05);
  transform: translateY(-2px);
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.fade-in {
  animation: fadeIn 0.4s ease forwards;
}

/* Markdown specific generated HTML */
blockquote {
  border-left: 4px solid var(--primary);
  padding: 1rem;
  background: var(--surface);
  border-radius: 0 0.5rem 0.5rem 0;
  margin: 1.5rem 0;
  font-style: italic;
}

/* Page Navigation */
.page-navigation {
  display: flex;
  justify-content: space-between;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  gap: 1rem;
}

.nav-btn {
  display: flex;
  flex-direction: column;
  padding: 1rem 1.5rem;
  background-color: var(--surface);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  color: var(--text-primary);
  text-decoration: none;
  min-width: 200px;
  transition: all 0.2s ease;
}

.nav-btn:hover {
  background-color: var(--surface-hover);
  border-color: var(--primary);
  transform: translateY(-2px);
  text-decoration: none;
  color: var(--text-primary);
}

.nav-btn.next {
  text-align: right;
  margin-left: auto;
}

.nav-btn span {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.25rem;
}

.nav-btn strong {
  font-size: 1.1rem;
  color: var(--primary);
}