/* Docker Tutorial - Main Stylesheet */
/* Modern, responsive design with Docker theme */

:root {
  /* Docker Brand Colors */
  --docker-blue: #0db7ed;
  --docker-dark-blue: #066da5;
  --docker-light-blue: #87ceeb;
  --docker-navy: #384d54;
  
  /* UI Colors */
  --primary: #2196f3;
  --primary-dark: #1976d2;
  --primary-light: #64b5f6;
  --secondary: #00bcd4;
  --success: #4caf50;
  --warning: #ff9800;
  --danger: #f44336;
  --info: #03a9f4;
  
  /* Neutral Colors */
  --gray-50: #fafafa;
  --gray-100: #f5f5f5;
  --gray-200: #eeeeee;
  --gray-300: #e0e0e0;
  --gray-400: #bdbdbd;
  --gray-500: #9e9e9e;
  --gray-600: #757575;
  --gray-700: #616161;
  --gray-800: #424242;
  --gray-900: #212121;
  
  /* Text Colors */
  --text-primary: #212121;
  --text-secondary: #757575;
  --text-light: #9e9e9e;
  --text-on-primary: #ffffff;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-xxl: 3rem;
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 8px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 16px rgba(0,0,0,0.15);
  --shadow-xl: 0 12px 24px rgba(0,0,0,0.18);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
}

/* Dark Mode Variables */
[data-theme="dark"] {
  --text-primary: #ffffff;
  --text-secondary: #b0b0b0;
  --text-light: #808080;
  --gray-50: #1a1a1a;
  --gray-100: #2a2a2a;
  --gray-200: #3a3a3a;
  --gray-300: #4a4a4a;
  --gray-800: #e0e0e0;
  --gray-900: #f5f5f5;
}

/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  position: relative;
  transition: background-color var(--transition-base), color var(--transition-base);
}

[data-theme="dark"] body {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
}

/* Container Layouts */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-lg);
}

.content-wrapper {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  margin: var(--spacing-lg);
  transition: background-color var(--transition-base);
}

[data-theme="dark"] .content-wrapper {
  background: var(--gray-100);
  box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}

/* Navigation Bar */
.tutorial-navigation {
  background: linear-gradient(135deg, var(--docker-blue) 0%, var(--docker-dark-blue) 100%);
  padding: var(--spacing-md) var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-md);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: var(--shadow-md);
}

.nav-group {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 1.2rem;
  font-weight: bold;
  color: white;
  text-decoration: none;
}

.nav-brand .docker-logo {
  width: 40px;
  height: 40px;
}

.nav-links {
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

.nav-link {
  color: white;
  text-decoration: none;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  background: rgba(255,255,255,0.1);
  font-size: 0.95rem;
}

.nav-link:hover {
  background: rgba(255,255,255,0.2);
  transform: translateY(-2px);
}

.nav-link.nav-previous::before {
  content: "←";
  font-size: 1.2em;
}

.nav-link.nav-next::after {
  content: "→";
  font-size: 1.2em;
}

.lesson-indicator {
  background: rgba(255,255,255,0.2);
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-lg);
  color: white;
  font-weight: 500;
}

/* Dark Mode Toggle */
.theme-toggle {
  background: rgba(255,255,255,0.2);
  border: 2px solid rgba(255,255,255,0.3);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xs) var(--spacing-sm);
  color: white;
  cursor: pointer;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.theme-toggle:hover {
  background: rgba(255,255,255,0.3);
  transform: scale(1.05);
}

/* Headers */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  margin: var(--spacing-lg) 0 var(--spacing-md) 0;
  color: var(--text-primary);
}

h1 {
  font-size: 2.5rem;
  text-align: center;
  color: var(--docker-dark-blue);
  margin: var(--spacing-xl) 0;
  position: relative;
  padding-bottom: var(--spacing-md);
}

h1::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100px;
  height: 4px;
  background: linear-gradient(90deg, var(--docker-blue), var(--docker-dark-blue));
  border-radius: var(--radius-sm);
}

h2 {
  font-size: 1.8rem;
  color: var(--docker-blue);
  margin-top: var(--spacing-xl);
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--gray-200);
}

h3 {
  font-size: 1.4rem;
  color: var(--text-primary);
  margin-top: var(--spacing-lg);
}

/* Paragraphs and Text */
p {
  margin: var(--spacing-md) 0;
  color: var(--text-secondary);
  line-height: 1.8;
}

main {
  padding: var(--spacing-xl);
}

strong {
  font-weight: 600;
  color: var(--text-primary);
}

/* Links */
a {
  color: var(--docker-blue);
  text-decoration: none;
  transition: color var(--transition-base);
}

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

/* Lists */
ul, ol {
  margin: var(--spacing-md) 0 var(--spacing-md) var(--spacing-xl);
}

ul li, ol li {
  margin: var(--spacing-sm) 0;
  color: var(--text-secondary);
}

/* Code Blocks and Syntax Highlighting */
pre {
  background: #1e1e1e;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
  overflow-x: auto;
  position: relative;
}

[data-theme="dark"] pre {
  background: #0a0a0a;
  border-color: var(--gray-700);
}

code {
  font-family: 'Fira Code', 'Courier New', monospace;
  font-size: 0.9em;
  background: var(--gray-100);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  color: var(--danger);
}

pre code {
  background: none;
  padding: 0;
  color: #f8f8f2;
  display: block;
  line-height: 1.5;
}

/* Copy Button for Code Blocks */
.code-container {
  position: relative;
  margin: var(--spacing-lg) 0;
}

.copy-button {
  position: absolute;
  top: var(--spacing-sm);
  right: var(--spacing-sm);
  background: var(--docker-blue);
  color: white;
  border: none;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.85rem;
  transition: all var(--transition-base);
  z-index: 10;
}

.copy-button:hover {
  background: var(--docker-dark-blue);
  transform: scale(1.05);
}

.copy-button.copied {
  background: var(--success);
}

.copy-button.copied::after {
  content: " ✓";
}

/* Docker Command Syntax Highlighting */
.docker-command {
  color: #50fa7b;
}

.docker-flag {
  color: #ff79c6;
}

.docker-image {
  color: #8be9fd;
}

.docker-container {
  color: #ffb86c;
}

.dockerfile-keyword {
  color: #ff79c6;
  font-weight: bold;
}

.dockerfile-arg {
  color: #50fa7b;
}

/* Responsive Canvas Container */
.canvas-container {
  position: relative;
  width: 100%;
  margin: var(--spacing-lg) 0;
  background: white;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-md);
  padding: var(--spacing-sm);
  overflow: hidden;
}

[data-theme="dark"] .canvas-container {
  background: var(--gray-200);
  border-color: var(--gray-600);
}

.responsive-canvas {
  position: relative;
  width: 100%;
  padding-bottom: 50%; /* 2:1 Aspect Ratio by default */
  height: 0;
  overflow: hidden;
}

.responsive-canvas.square {
  padding-bottom: 100%; /* 1:1 Aspect Ratio */
}

.responsive-canvas.wide {
  padding-bottom: 40%; /* 5:2 Aspect Ratio */
}

.responsive-canvas.tall {
  padding-bottom: 75%; /* 4:3 Aspect Ratio */
}

.responsive-canvas canvas,
.responsive-canvas svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

/* Lesson Cards */
.lessons-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.lesson-card {
  background: linear-gradient(135deg, var(--docker-blue) 0%, var(--docker-dark-blue) 100%);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  color: white;
  text-decoration: none;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
  display: block;
}

.lesson-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(13, 183, 237, 0.3);
  text-decoration: none;
}

.lesson-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(255, 255, 255, 0.1);
  transform: translateX(-100%);
  transition: transform var(--transition-slow);
}

.lesson-card:hover::before {
  transform: translateX(0);
}

.lesson-number {
  background: rgba(255, 255, 255, 0.2);
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-lg);
  font-weight: bold;
  margin-bottom: var(--spacing-sm);
}

.lesson-title {
  font-size: 1.4em;
  font-weight: bold;
  margin-bottom: var(--spacing-sm);
  color: white;
}

.lesson-description {
  font-size: 0.95em;
  opacity: 0.95;
  line-height: 1.5;
  color: white;
}

.lesson-topics {
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.3);
  font-size: 0.85em;
  opacity: 0.9;
  color: white;
}

/* Interactive Terminal */
.terminal-container {
  background: #1e1e1e;
  border-radius: var(--radius-md);
  padding: 0;
  margin: var(--spacing-lg) 0;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.terminal-header {
  background: linear-gradient(90deg, #4a4a4a, #3a3a3a);
  padding: var(--spacing-sm) var(--spacing-md);
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.terminal-button {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #ff5f56;
}

.terminal-button.yellow {
  background: #ffbd2e;
}

.terminal-button.green {
  background: #27c93f;
}

.terminal-title {
  color: #999;
  font-size: 0.85rem;
  margin-left: var(--spacing-md);
  font-family: monospace;
}

.terminal-body {
  padding: var(--spacing-md);
  font-family: 'Fira Code', 'Courier New', monospace;
  color: #f8f8f2;
  min-height: 200px;
  max-height: 500px;
  overflow-y: auto;
}

.terminal-line {
  margin: var(--spacing-xs) 0;
  display: flex;
  align-items: center;
}

.terminal-prompt {
  color: #50fa7b;
  margin-right: var(--spacing-sm);
}

.terminal-input {
  background: transparent;
  border: none;
  color: #f8f8f2;
  outline: none;
  flex: 1;
  font-family: inherit;
  font-size: inherit;
}

.terminal-output {
  color: #8be9fd;
  margin: var(--spacing-sm) 0;
  padding-left: var(--spacing-lg);
}

/* Progress Bar */
.progress-section {
  background: var(--gray-100);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin: var(--spacing-xl) 0;
  text-align: center;
}

[data-theme="dark"] .progress-section {
  background: var(--gray-200);
}

.progress-bar {
  background: var(--gray-300);
  border-radius: var(--radius-md);
  height: 30px;
  overflow: hidden;
  margin: var(--spacing-lg) 0;
}

.progress-fill {
  background: linear-gradient(90deg, var(--docker-blue), var(--docker-dark-blue));
  height: 100%;
  width: 0%;
  transition: width 2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: bold;
}

/* Features Grid */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.feature {
  text-align: center;
  padding: var(--spacing-lg);
  background: var(--gray-100);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

[data-theme="dark"] .feature {
  background: var(--gray-200);
}

.feature:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.feature-icon {
  font-size: 2em;
  margin-bottom: var(--spacing-sm);
}

.feature-title {
  font-weight: bold;
  margin-bottom: var(--spacing-xs);
  color: var(--text-primary);
}

.feature-description {
  font-size: 0.9em;
  color: var(--text-secondary);
}

/* Command List */
.command-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-md);
  margin: var(--spacing-lg) 0;
}

.command {
  background: var(--gray-900);
  color: var(--success);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-sm);
  font-family: 'Fira Code', monospace;
  font-size: 0.9em;
  border-left: 4px solid var(--docker-blue);
  position: relative;
  cursor: pointer;
  transition: all var(--transition-base);
}

.command:hover {
  background: #1a1a1a;
  transform: translateX(5px);
}

/* Mermaid Diagrams */
.mermaid {
  margin: var(--spacing-xl) auto;
  padding: var(--spacing-lg);
  background: white;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-md);
  text-align: center;
  overflow-x: auto;
}

[data-theme="dark"] .mermaid {
  background: var(--gray-100);
  border-color: var(--gray-600);
}

/* Footer */
.footer {
  text-align: center;
  margin-top: var(--spacing-xxl);
  padding-top: var(--spacing-xl);
  border-top: 1px solid var(--gray-300);
  color: var(--text-secondary);
}

.footer a {
  color: var(--docker-blue);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

/* Animations */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-20px); }
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.whale {
  text-align: center;
  font-size: 4em;
  margin: var(--spacing-lg) 0;
  animation: float 3s ease-in-out infinite;
  cursor: pointer;
}

/* Utility Classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

.px-1 { padding-left: var(--spacing-sm); padding-right: var(--spacing-sm); }
.px-2 { padding-left: var(--spacing-md); padding-right: var(--spacing-md); }
.px-3 { padding-left: var(--spacing-lg); padding-right: var(--spacing-lg); }
.px-4 { padding-left: var(--spacing-xl); padding-right: var(--spacing-xl); }

.py-1 { padding-top: var(--spacing-sm); padding-bottom: var(--spacing-sm); }
.py-2 { padding-top: var(--spacing-md); padding-bottom: var(--spacing-md); }
.py-3 { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }
.py-4 { padding-top: var(--spacing-xl); padding-bottom: var(--spacing-xl); }

/* Responsive Design */
@media (max-width: 768px) {
  .tutorial-navigation {
    flex-direction: column;
    text-align: center;
  }
  
  .nav-links {
    flex-direction: column;
    width: 100%;
  }
  
  .nav-link {
    width: 100%;
    justify-content: center;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.5rem;
  }
  
  .lessons-grid {
    grid-template-columns: 1fr;
  }
  
  .command-list {
    grid-template-columns: 1fr;
  }
  
  main {
    padding: var(--spacing-md);
  }
  
  .content-wrapper {
    margin: var(--spacing-sm);
    border-radius: var(--radius-md);
  }
}

@media (max-width: 480px) {
  .features {
    grid-template-columns: 1fr;
  }
  
  h1 {
    font-size: 1.75rem;
  }
  
  .whale {
    font-size: 3em;
  }
}

/* Print Styles */
@media print {
  body {
    background: white;
  }
  
  .tutorial-navigation,
  .theme-toggle,
  .copy-button {
    display: none;
  }
  
  .content-wrapper {
    box-shadow: none;
    margin: 0;
  }
  
  .lesson-card {
    page-break-inside: avoid;
  }
}