/* CSS Variables - Design System */
:root {
  --color-bg: #f5f5f5;
  --color-text: #000000;
  --color-white: #ffffff;
  --color-muted: #6b7280;
  --color-primary: #000000;
  --color-border: #e5e7eb;

  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --container-max: 1200px;
  --container-padding: 1.5rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Skip Link for Accessibility */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: var(--color-white);
  padding: var(--spacing-sm);
  text-decoration: none;
  z-index: 100;
}

.skip-link:focus {
  top: 0;
}

/* Container */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Header */
.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 50;
}

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

.logo {
  height: 40px;
  width: auto;
}

.main-nav ul {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
  align-items: center;
}

.main-nav a {
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

.main-nav a:hover {
  color: var(--color-muted);
}

/* Breadcrumbs */
.breadcrumb {
  padding: var(--spacing-md) 0;
  font-size: 0.875rem;
}

.breadcrumb ol {
  display: flex;
  gap: var(--spacing-xs);
  list-style: none;
  flex-wrap: wrap;
}

.breadcrumb li {
  display: flex;
  align-items: center;
}

.breadcrumb li::after {
  content: "/";
  margin-left: var(--spacing-xs);
  color: var(--color-muted);
}

.breadcrumb li:last-child::after {
  content: "";
}

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

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

.breadcrumb span {
  color: var(--color-muted);
}

/* Main Content */
main {
  padding: var(--spacing-xl) 0;
  min-height: 60vh;
}

/* Tutorial Article */
.tutorial-article {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

/* Hero Section */
.tutorial-hero {
  margin-bottom: var(--spacing-xl);
  text-align: center;
}

.tutorial-hero h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  line-height: 1.2;
}

.tutorial-hero .lead {
  font-size: 1.25rem;
  color: var(--color-muted);
  margin-bottom: var(--spacing-lg);
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.hero-image {
  width: 100%;
  max-width: 800px;
  height: auto;
  border-radius: var(--radius-md);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  margin: 0 auto;
  display: block;
}

/* Table of Contents */
.table-of-contents {
  background: var(--color-bg);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.table-of-contents h2 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
}

.table-of-contents ol {
  list-style: decimal;
  padding-left: var(--spacing-lg);
}

.table-of-contents li {
  margin-bottom: var(--spacing-sm);
}

.table-of-contents a {
  color: var(--color-primary);
  text-decoration: none;
}

.table-of-contents a:hover {
  text-decoration: underline;
}

/* Tutorial Steps */
.tutorial-steps {
  margin-bottom: var(--spacing-xl);
}

.step {
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-xl);
  border-bottom: 1px solid var(--color-border);
}

.step:last-child {
  border-bottom: none;
}

.step h3 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: 50%;
  font-size: 1.25rem;
  font-weight: 700;
  flex-shrink: 0;
}

.step-content {
  margin-bottom: var(--spacing-md);
}

.step-content p {
  margin-bottom: var(--spacing-md);
  font-size: 1.125rem;
}

.step-content ul {
  list-style: disc;
  padding-left: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
}

.step-content li {
  margin-bottom: var(--spacing-xs);
}

.step-image {
  width: 100%;
  max-width: 800px;
  height: auto;
  border-radius: var(--radius-md);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--color-border);
}

/* Tips & Best Practices */
.tips-section,
.issues-section {
  background: var(--color-bg);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.tips-section h2,
.issues-section h2 {
  font-size: 1.75rem;
  margin-bottom: var(--spacing-md);
}

.tips-section ul,
.issues-section ul {
  list-style: disc;
  padding-left: var(--spacing-lg);
}

.tips-section li,
.issues-section li {
  margin-bottom: var(--spacing-md);
  font-size: 1.125rem;
}

.tips-section strong,
.issues-section strong {
  color: var(--color-primary);
}

/* Related Tutorials */
.related-tutorials {
  margin-bottom: var(--spacing-xl);
}

.related-tutorials h2 {
  font-size: 1.75rem;
  margin-bottom: var(--spacing-lg);
  text-align: center;
}

.tutorial-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

.tutorial-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  text-decoration: none;
  color: var(--color-text);
  transition: transform 0.2s, box-shadow 0.2s;
}

.tutorial-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.tutorial-card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.tutorial-card-content {
  padding: var(--spacing-md);
}

.tutorial-card h3 {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-sm);
}

.tutorial-card p {
  color: var(--color-muted);
  font-size: 0.938rem;
}

/* CTA Section */
.cta-section {
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  text-align: center;
}

.cta-section h2 {
  font-size: 2rem;
  margin-bottom: var(--spacing-md);
}

.cta-section p {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-lg);
  opacity: 0.9;
}

.cta-buttons {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--radius-sm);
  font-weight: 600;
  text-decoration: none;
  transition: opacity 0.2s, transform 0.2s;
  font-size: 1.125rem;
}

.btn:hover {
  opacity: 0.9;
  transform: translateY(-2px);
}

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

.btn-secondary {
  background: transparent;
  color: var(--color-white);
  border: 2px solid var(--color-white);
}

/* Footer */
.site-footer {
  background: var(--color-primary);
  color: var(--color-white);
  padding: var(--spacing-xl) 0 var(--spacing-lg) 0;
  margin-top: var(--spacing-2xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
}

.footer-section h3 {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
}

.footer-section ul {
  list-style: none;
}

.footer-section li {
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  transition: color 0.2s;
}

.footer-section a:hover {
  color: var(--color-white);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  color: rgba(255, 255, 255, 0.6);
}

/* Responsive Design */
@media (max-width: 768px) {
  .tutorial-hero h1 {
    font-size: 2rem;
  }

  .tutorial-hero .lead {
    font-size: 1.125rem;
  }

  .main-nav ul {
    gap: var(--spacing-md);
    font-size: 0.875rem;
  }

  .tutorial-article {
    padding: var(--spacing-md);
  }

  .step h3 {
    font-size: 1.5rem;
  }

  .step-number {
    width: 32px;
    height: 32px;
    font-size: 1rem;
  }

  .cta-buttons {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

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