/* ============================================
   openclaw.ai TUTORIAL WEBSITE - DESIGN SYSTEM
   ============================================ */

/* CSS Custom Properties */
:root {
  /* Colors - Light Theme */
  --color-primary: #6366f1;
  --color-primary-dark: #4f46e5;
  --color-primary-light: #818cf8;
  --color-secondary: #0ea5e9;
  --color-accent: #f59e0b;

  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-info: #3b82f6;

  --color-bg: #ffffff;
  --color-bg-secondary: #f8fafc;
  --color-bg-tertiary: #f1f5f9;
  --color-surface: #ffffff;
  --color-surface-elevated: #ffffff;

  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #94a3b8;
  --color-text-inverse: #ffffff;

  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;

  /* Code Block Colors */
  --color-code-bg: #1e293b;
  --color-code-text: #e2e8f0;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.75;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;

  /* Z-Index */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal: 400;
  --z-tooltip: 500;

  /* Layout */
  --container-max: 1280px;
  --sidebar-width: 280px;
  --header-height: 72px;
}

/* Dark Theme */
[data-theme="dark"] {
  --color-bg: #0f172a;
  --color-bg-secondary: #1e293b;
  --color-bg-tertiary: #334155;
  --color-surface: #1e293b;
  --color-surface-elevated: #334155;

  --color-text: #f1f5f9;
  --color-text-secondary: #cbd5e1;
  --color-text-muted: #64748b;

  --color-border: #334155;
  --color-border-light: #1e293b;

  --color-code-bg: #0f172a;

  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4), 0 2px 4px -2px rgb(0 0 0 / 0.3);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.4), 0 4px 6px -4px rgb(0 0 0 / 0.3);
}

/* ============================================
   BASE RESET & TYPOGRAPHY
   ============================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: var(--leading-tight);
  color: var(--color-text);
}

h1 {
  font-size: var(--text-4xl);
}

h2 {
  font-size: var(--text-3xl);
}

h3 {
  font-size: var(--text-2xl);
}

h4 {
  font-size: var(--text-xl);
}

h5 {
  font-size: var(--text-lg);
}

h6 {
  font-size: var(--text-base);
}

p {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
}

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

a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ============================================
   LAYOUT UTILITIES
   ============================================ */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.section {
  padding: var(--space-16) 0;
}

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.items-center {
  align-items: center;
}

.justify-center {
  justify-content: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-2 {
  gap: var(--space-2);
}

.gap-4 {
  gap: var(--space-4);
}

.gap-6 {
  gap: var(--space-6);
}

.gap-8 {
  gap: var(--space-8);
}

.grid {
  display: grid;
}

.grid-cols-1 {
  grid-template-columns: repeat(1, 1fr);
}

.grid-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-cols-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (min-width: 640px) {
  .sm\:grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 768px) {
  .md\:grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1024px) {
  .lg\:grid-cols-4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ============================================
   HEADER & NAVIGATION
   ============================================ */
.header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
  backdrop-filter: blur(12px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 800;
  font-size: var(--text-lg);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  list-style: none;
}

.nav-link {
  padding: var(--space-2) var(--space-4);
  color: var(--color-text-secondary);
  font-weight: 500;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
  background: var(--color-bg-secondary);
  text-decoration: none;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2) var(--space-4);
  gap: var(--space-2);
  transition: all var(--transition-fast);
}

.search-box:focus-within {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgb(99 102 241 / 0.1);
}

.search-input {
  border: none;
  background: transparent;
  font-size: var(--text-sm);
  color: var(--color-text);
  outline: none;
  width: 200px;
}

.search-input::placeholder {
  color: var(--color-text-muted);
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  background: var(--color-bg-tertiary);
  color: var(--color-text);
}

/* Mobile Menu */
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
  background: transparent;
  border: none;
  cursor: pointer;
}

.mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

@media (max-width: 1023px) {
  .nav-menu {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    flex-direction: column;
    background: var(--color-surface);
    padding: var(--space-6);
    transform: translateX(-100%);
    transition: transform var(--transition-base);
    z-index: var(--z-fixed);
  }

  .nav-menu.active {
    transform: translateX(0);
  }

  .nav-link {
    width: 100%;
    padding: var(--space-4);
  }

  .mobile-toggle {
    display: flex;
  }

  .search-box {
    display: none;
  }
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
  background: linear-gradient(135deg, var(--color-bg-secondary) 0%, var(--color-bg) 100%);
  padding: var(--space-20) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.05) 0%, transparent 50%);
  animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {

  0%,
  100% {
    transform: scale(1);
    opacity: 0.5;
  }

  50% {
    transform: scale(1.1);
    opacity: 0.8;
  }
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: var(--text-5xl);
  margin-bottom: var(--space-6);
  background: linear-gradient(135deg, var(--color-text), var(--color-primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: var(--text-xl);
  color: var(--color-text-secondary);
  max-width: 700px;
  margin: 0 auto var(--space-8);
}

@media (max-width: 768px) {
  .hero h1 {
    font-size: var(--text-3xl);
  }

  .hero-subtitle {
    font-size: var(--text-lg);
  }
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
  font-weight: 600;
  border-radius: var(--radius-lg);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-text-inverse);
  box-shadow: 0 4px 14px rgb(99 102 241 / 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgb(99 102 241 / 0.5);
  text-decoration: none;
  color: var(--color-text-inverse);
}

.btn-secondary {
  background: var(--color-bg-secondary);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-bg-tertiary);
  text-decoration: none;
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-lg);
}

/* ============================================
   TUTORIAL CARDS
   ============================================ */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-6);
}

.tutorial-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  transition: all var(--transition-base);
  display: flex;
  flex-direction: column;
}

.tutorial-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card-header {
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

.card-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-2xl);
  flex-shrink: 0;
}

.card-meta {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.card-title {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
}

.card-badges {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.badge-beginner {
  background: rgb(16 185 129 / 0.15);
  color: var(--color-success);
}

.badge-intermediate {
  background: rgb(245 158 11 / 0.15);
  color: var(--color-warning);
}

.badge-advanced {
  background: rgb(239 68 68 / 0.15);
  color: var(--color-error);
}

.badge-time {
  background: var(--color-bg-secondary);
  color: var(--color-text-muted);
}

.card-description {
  flex: 1;
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
}

.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border-light);
}

.card-link {
  font-weight: 600;
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.card-link:hover {
  gap: var(--space-3);
}

/* ============================================
   FILTER BAR
   ============================================ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-8);
  padding: var(--space-4);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
}

.filter-group {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.filter-label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-muted);
}

.filter-select {
  padding: var(--space-2) var(--space-4);
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--color-text);
  cursor: pointer;
}

/* ============================================
   TUTORIAL PAGE LAYOUT
   ============================================ */
.tutorial-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--space-8) var(--space-6);
}

@media (min-width: 1024px) {
  .tutorial-layout {
    grid-template-columns: var(--sidebar-width) 1fr;
  }
}

/* Sidebar / Table of Contents */
.sidebar {
  display: none;
}

@media (min-width: 1024px) {
  .sidebar {
    display: block;
    position: sticky;
    top: calc(var(--header-height) + var(--space-8));
    height: fit-content;
    max-height: calc(100vh - var(--header-height) - var(--space-16));
    overflow-y: auto;
  }
}

.toc {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}

.toc-title {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: var(--space-4);
}

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

.toc-item {
  margin-bottom: var(--space-2);
}

.toc-link {
  display: block;
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  border-left: 2px solid transparent;
  transition: all var(--transition-fast);
}

.toc-link:hover,
.toc-link.active {
  color: var(--color-primary);
  background: var(--color-bg-secondary);
  border-left-color: var(--color-primary);
  text-decoration: none;
}

.toc-link.depth-2 {
  padding-left: var(--space-6);
  font-size: var(--text-xs);
}

/* Tutorial Content */
.tutorial-content {
  max-width: 800px;
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.breadcrumbs a {
  color: var(--color-text-muted);
}

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

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

/* Tutorial Header */
.tutorial-header {
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-8);
  border-bottom: 1px solid var(--color-border);
}

.tutorial-header h1 {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-4);
}

.tutorial-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.tutorial-meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Progress Indicator */
.progress-bar {
  position: sticky;
  top: var(--header-height);
  z-index: var(--z-sticky);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-3) 0;
}

.progress-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.progress-track {
  flex: 1;
  height: 6px;
  background: var(--color-bg-tertiary);
  border-radius: var(--radius-full);
  margin: 0 var(--space-4);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
}

.progress-text {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-secondary);
  white-space: nowrap;
}

/* ============================================
   CONTENT ELEMENTS
   ============================================ */

/* Prerequisites Checklist */
.prerequisites {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  margin-bottom: var(--space-8);
}

.prerequisites h3 {
  font-size: var(--text-lg);
  margin-bottom: var(--space-4);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.checklist {
  list-style: none;
}

.checklist li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-2) 0;
  color: var(--color-text-secondary);
}

.checklist input[type="checkbox"] {
  width: 20px;
  height: 20px;
  accent-color: var(--color-primary);
  cursor: pointer;
}

/* Step Container */
.step {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  margin-bottom: var(--space-6);
}

.step-header {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

.step-number {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: white;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: var(--text-sm);
  flex-shrink: 0;
}

.step-title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
}

/* Code Blocks */
.code-block {
  position: relative;
  margin: var(--space-4) 0;
  background: var(--color-code-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-2) var(--space-4);
  background: rgba(0, 0, 0, 0.2);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.code-lang {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
}

.copy-btn {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-3);
  background: rgba(255, 255, 255, 0.1);
  border: none;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  color: var(--color-code-text);
}

.copy-btn.copied {
  background: var(--color-success);
  color: white;
}

.code-block pre {
  margin: 0;
  padding: var(--space-4);
  overflow-x: auto;
}

.code-block code {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-code-text);
}

/* Expected Output Box */
.expected-output {
  background: var(--color-bg-secondary);
  border-left: 4px solid var(--color-info);
  padding: var(--space-4);
  margin: var(--space-4) 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.expected-output-title {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-info);
  margin-bottom: var(--space-2);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.expected-output pre {
  background: var(--color-code-bg);
  padding: var(--space-3);
  border-radius: var(--radius-md);
  overflow-x: auto;
  font-size: var(--text-sm);
  color: var(--color-code-text);
}

/* Callout Boxes */
.callout {
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-lg);
  margin: var(--space-4) 0;
  display: flex;
  gap: var(--space-3);
}

.callout-icon {
  font-size: var(--text-xl);
  flex-shrink: 0;
}

.callout-content {
  flex: 1;
}

.callout-title {
  font-weight: 700;
  font-size: var(--text-sm);
  margin-bottom: var(--space-1);
}

.callout-text {
  font-size: var(--text-sm);
  margin: 0;
}

.callout-note {
  background: rgb(59 130 246 / 0.1);
  border: 1px solid rgb(59 130 246 / 0.3);
}

.callout-note .callout-title,
.callout-note .callout-icon {
  color: var(--color-info);
}

.callout-tip {
  background: rgb(16 185 129 / 0.1);
  border: 1px solid rgb(16 185 129 / 0.3);
}

.callout-tip .callout-title,
.callout-tip .callout-icon {
  color: var(--color-success);
}

.callout-warning {
  background: rgb(245 158 11 / 0.1);
  border: 1px solid rgb(245 158 11 / 0.3);
}

.callout-warning .callout-title,
.callout-warning .callout-icon {
  color: var(--color-warning);
}

.callout-danger {
  background: rgb(239 68 68 / 0.1);
  border: 1px solid rgb(239 68 68 / 0.3);
}

.callout-danger .callout-title,
.callout-danger .callout-icon {
  color: var(--color-error);
}

/* Collapsible Sections */
.collapsible {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin: var(--space-4) 0;
  overflow: hidden;
}

.collapsible-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  background: var(--color-bg-secondary);
  cursor: pointer;
  user-select: none;
  transition: background var(--transition-fast);
}

.collapsible-header:hover {
  background: var(--color-bg-tertiary);
}

.collapsible-title {
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.collapsible-icon {
  transition: transform var(--transition-base);
}

.collapsible.open .collapsible-icon {
  transform: rotate(180deg);
}

.collapsible-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.collapsible.open .collapsible-content {
  max-height: 2000px;
}

.collapsible-inner {
  padding: var(--space-4);
}

/* Troubleshooting Items */
.troubleshoot-item {
  padding: var(--space-4);
  border-bottom: 1px solid var(--color-border-light);
}

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

.troubleshoot-error {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  color: var(--color-error);
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.troubleshoot-solution {
  padding-left: var(--space-6);
  color: var(--color-text-secondary);
}

/* FAQ Section */
.faq-item {
  border-bottom: 1px solid var(--color-border-light);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) 0;
  font-weight: 600;
  cursor: pointer;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-base);
}

.faq-item.open .faq-answer {
  max-height: 500px;
}

.faq-answer-inner {
  padding-bottom: var(--space-4);
  color: var(--color-text-secondary);
}

/* Related Tutorials */
.related-tutorials {
  margin-top: var(--space-12);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
}

.related-tutorials h3 {
  margin-bottom: var(--space-6);
}

/* Feedback Section */
.feedback-section {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  margin-top: var(--space-8);
  text-align: center;
}

.feedback-question {
  font-weight: 600;
  margin-bottom: var(--space-4);
}

.feedback-buttons {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
}

.feedback-btn {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.feedback-btn:hover {
  border-color: var(--color-primary);
}

.feedback-btn.active {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--space-16) 0 var(--space-8);
  margin-top: var(--space-16);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-8);
  margin-bottom: var(--space-8);
}

.footer-col h4 {
  font-size: var(--text-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

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

.footer-links li {
  margin-bottom: var(--space-2);
}

.footer-links a {
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
}

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

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
}

.footer-copyright {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

.social-links {
  display: flex;
  gap: var(--space-4);
}

.social-link {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
}

.social-link:hover {
  background: var(--color-primary);
  color: white;
}

/* Newsletter */
.newsletter {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}

.newsletter h4 {
  margin-bottom: var(--space-2);
}

.newsletter p {
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
}

.newsletter-form {
  display: flex;
  gap: var(--space-2);
}

.newsletter-input {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  background: var(--color-bg);
  color: var(--color-text);
}

.newsletter-input:focus {
  outline: none;
  border-color: var(--color-primary);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

.mt-4 {
  margin-top: var(--space-4);
}

.mt-8 {
  margin-top: var(--space-8);
}

.mb-4 {
  margin-bottom: var(--space-4);
}

.mb-8 {
  margin-bottom: var(--space-8);
}

.hidden {
  display: none !important;
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* Scroll to top button */
.scroll-top {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  width: 48px;
  height: 48px;
  background: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  z-index: var(--z-fixed);
  box-shadow: var(--shadow-lg);
}

.scroll-top.visible {
  opacity: 1;
  visibility: visible;
}

.scroll-top:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

/* Platform Icons */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-4);
  margin-top: var(--space-8);
}

.platform-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  text-decoration: none;
  transition: all var(--transition-base);
}

.platform-item:hover {
  border-color: var(--color-primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  text-decoration: none;
}

.platform-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
}

.platform-name {
  font-weight: 600;
  color: var(--color-text);
  font-size: var(--text-sm);
  text-align: center;
}

/* Video placeholder */
.video-placeholder {
  background: var(--color-bg-tertiary);
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-12);
  text-align: center;
  margin: var(--space-6) 0;
}

.video-placeholder-icon {
  font-size: 48px;
  margin-bottom: var(--space-4);
  opacity: 0.5;
}

.video-placeholder-text {
  color: var(--color-text-muted);
}

/* ============================================
   PLATFORM ICONS (SVG)
   ============================================ */
.card-icon img,
.platform-icon img {
  width: 32px;
  height: 32px;
  object-fit: contain;
}

.card-icon.icon-windows {
  background: linear-gradient(135deg, #00a4ef, #0078d4);
}

.card-icon.icon-macos {
  background: linear-gradient(135deg, #555555, #333333);
}

.card-icon.icon-ubuntu {
  background: linear-gradient(135deg, #e95420, #dd4814);
}

.card-icon.icon-fedora {
  background: linear-gradient(135deg, #3c6eb4, #294172);
}

.card-icon.icon-arch {
  background: linear-gradient(135deg, #1793d1, #126a9c);
}

.card-icon.icon-docker {
  background: linear-gradient(135deg, #2496ed, #1a6fc9);
}

.card-icon.icon-raspberry {
  background: linear-gradient(135deg, #c51a4a, #8f1339);
}

.card-icon.icon-recycle {
  background: linear-gradient(135deg, #22c55e, #16a34a);
}

.card-icon.icon-wsl {
  background: linear-gradient(135deg, #00a4ef, #e95420);
}

.card-icon.icon-hostinger {
  background: linear-gradient(135deg, #673de6, #5025d1);
}

.card-icon.icon-digitalocean {
  background: linear-gradient(135deg, #0080ff, #0050cc);
}

.card-icon.icon-aws {
  background: linear-gradient(135deg, #ff9900, #cc7a00);
}

.card-icon.icon-gcp {
  background: linear-gradient(135deg, #4285f4, #ea4335);
}

.card-icon.icon-linode {
  background: linear-gradient(135deg, #00b050, #008040);
}

.card-icon.icon-vultr {
  background: linear-gradient(135deg, #007bfc, #0056b3);
}

.card-icon.icon-ssl {
  background: linear-gradient(135deg, #10b981, #059669);
}

.card-icon.icon-kubernetes {
  background: linear-gradient(135deg, #326ce5, #2454b5);
}

.card-icon.icon-compose {
  background: linear-gradient(135deg, #2496ed, #1a6fc9);
}

.card-icon.icon-airgap {
  background: linear-gradient(135deg, #6366f1, #4f46e5);
}/* ============================================
   TUTORIAL LAYOUT (Restored)
   ============================================ */

.tutorial-layout {
    display: flex;
    flex-direction: row;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-8) var(--space-4);
    gap: var(--space-8);
    position: relative;
    min-height: 80vh;
}

.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    position: sticky;
    top: calc(var(--header-height) + var(--space-4));
    height: calc(100vh - var(--header-height) - var(--space-8));
    overflow-y: auto;
    padding-right: var(--space-4);
    border-right: 1px solid var(--color-border-light);
    display: block;
    /* Ensure it behaves as block */
}

.tutorial-content {
    flex: 1;
    min-width: 0;
    /* Prevent flex overflow with code blocks */
    max-width: 100%;
}

.toc-title {
    font-size: var(--text-sm);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    margin-bottom: var(--space-4);
}

.toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.toc-link {
    display: block;
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    padding: var(--space-2) 0;
    border-left: 2px solid transparent;
    padding-left: var(--space-3);
    transition: all var(--transition-fast);
}

.toc-link:hover,
.toc-link.active {
    color: var(--color-primary);
    border-left-color: var(--color-primary);
    background-color: var(--color-bg-secondary);
}

/* Responsive */
@media (max-width: 1024px) {
    .tutorial-layout {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        position: relative;
        top: 0;
        border-right: none;
        border-bottom: 1px solid var(--color-border);
        padding-bottom: var(--space-6);
        margin-bottom: var(--space-6);
    }

    .toc-list {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: var(--space-2);
    }
}

/* ============================================
   ACCESSIBILITY & UI/UX FIXES
   ============================================ */

/* Focus visible styles for all interactive elements */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn:focus-visible,
.nav-link:focus-visible,
.card-link:focus-visible,
.social-link:focus-visible,
.theme-toggle:focus-visible,
.mobile-toggle:focus-visible,
.scroll-top:focus-visible,
.copy-btn:focus-visible,
.platform-item:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-md);
}

.collapsible-header:focus-visible,
.faq-question:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: -2px;
  border-radius: var(--radius-md);
}

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Better mobile support for small phones */
@media (max-width: 374px) {
  .container {
    padding: 0 var(--space-3);
  }

  .hero h1 {
    font-size: var(--text-2xl);
  }

  .hero-subtitle {
    font-size: var(--text-base);
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .platform-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .filter-bar {
    flex-direction: column;
    gap: var(--space-2);
  }
}

/* Copy button visibility improvement */
.copy-btn {
  background: rgba(255, 255, 255, 0.2);
  font-weight: 500;
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.35);
}

/* Code block horizontal scroll indicator */
.code-block pre::-webkit-scrollbar {
  height: 6px;
}

.code-block pre::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 3px;
}

.code-block pre::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.2);
  border-radius: 3px;
}

/* Quick install highlight on homepage */
.quick-install .code-block {
  border: 1px solid var(--color-primary);
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.15);
}

[data-theme="dark"] .quick-install .code-block {
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.25);
}

/* Hero Badge */
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-5);
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: var(--space-6);
}

/* Features Section */
.features-section {
  padding: var(--space-12) 0;
  border-bottom: 1px solid var(--color-border);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-8);
  text-align: center;
}

.feature-item {
  padding: var(--space-6);
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: var(--space-4);
}

.feature-title {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}

.feature-desc {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: var(--leading-relaxed);
  margin: 0;
}

/* Section Headers */
.section-header {
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-4);
  border-bottom: 2px solid var(--color-border-light);
}

.section-header h2 {
  margin-bottom: var(--space-2);
}

.section-header p {
  color: var(--color-text-secondary);
  font-size: var(--text-lg);
  margin: 0;
}