:root {
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-secondary: #10b981;
  --color-accent: #f59e0b;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-bg: #ffffff;
  --color-bg-secondary: #f9fafb;
  --color-bg-tertiary: #f3f4f6;
  --color-border: #e5e7eb;
  --color-code-bg: #1e293b;
  --color-success: #10b981;
  --color-error: #ef4444;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;

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

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

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

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.site-header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  background-color: rgba(255, 255, 255, 0.95);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-lg);
}

.site-branding {
  flex: 1;
}

.site-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
  display: inline-block;
  transition: color 0.2s;
}

.site-title:hover {
  color: var(--color-primary-hover);
}

.site-tagline {
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-top: 0.25rem;
}

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

.nav-link {
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-md);
  transition: all 0.2s;
}

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

.search-toggle {
  background: none;
  border: none;
  color: var(--color-text);
  cursor: pointer;
  padding: var(--spacing-xs);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

.search-toggle:hover {
  background-color: var(--color-bg-tertiary);
  color: var(--color-primary);
}

.search-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  z-index: 1000;
  display: none;
  align-items: flex-start;
  justify-content: center;
  padding-top: 10vh;
  backdrop-filter: blur(4px);
}

.search-overlay.active {
  display: flex;
}

.search-container {
  width: 90%;
  max-width: 600px;
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
}

.search-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
}

.search-input {
  flex: 1;
  border: none;
  font-size: 1.125rem;
  padding: var(--spacing-xs);
  outline: none;
  font-family: var(--font-sans);
}

.search-close {
  background: none;
  border: none;
  color: var(--color-text-light);
  cursor: pointer;
  padding: var(--spacing-xs);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  transition: all 0.2s;
}

.search-close:hover {
  background-color: var(--color-bg-tertiary);
  color: var(--color-text);
}

.search-results {
  max-height: 60vh;
  overflow-y: auto;
  padding: var(--spacing-md);
}

.search-result-item {
  padding: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
  cursor: pointer;
  transition: background-color 0.2s;
}

.search-result-item:hover {
  background-color: var(--color-bg-secondary);
}

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

.search-result-title {
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.search-result-excerpt {
  font-size: 0.875rem;
  color: var(--color-text-light);
  line-height: 1.5;
}

.home-hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: var(--spacing-2xl) 0;
  margin-bottom: var(--spacing-xl);
}

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

.hero-subtitle {
  font-size: 1.25rem;
  opacity: 0.95;
  max-width: 700px;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  color: var(--color-text);
}

.featured-posts {
  margin-bottom: var(--spacing-2xl);
}

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

.post-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all 0.3s;
  height: 100%;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.post-card-content {
  padding: var(--spacing-lg);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.post-categories {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-sm);
}

.category-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background-color: var(--color-bg-tertiary);
  color: var(--color-primary);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.025em;
}

.post-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  line-height: 1.3;
}

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

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

.post-excerpt {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  flex: 1;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  align-items: center;
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
}

.post-meta time {
  display: flex;
  align-items: center;
}

.read-more {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  transition: gap 0.2s;
  gap: 0.25rem;
}

.read-more:hover {
  gap: 0.5rem;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-lg);
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.category-filter {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
}

.filter-btn {
  padding: 0.5rem 1rem;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  transition: all 0.2s;
  color: var(--color-text);
}

.filter-btn:hover {
  background: var(--color-bg-tertiary);
  border-color: var(--color-primary);
}

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

.posts-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.post-item {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  transition: all 0.3s;
}

.post-item:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
}

.post-item.hidden {
  display: none;
}

.post-item-header {
  margin-bottom: var(--spacing-sm);
}

.post {
  margin-bottom: var(--spacing-xl);
}

.post-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: var(--spacing-2xl) 0;
  margin-bottom: var(--spacing-xl);
}

.post-header .post-categories {
  margin-bottom: var(--spacing-md);
}

.post-header .category-badge {
  background-color: rgba(255, 255, 255, 0.2);
  color: white;
}

.post-header .post-title {
  font-size: 2.5rem;
  color: white;
  margin-bottom: var(--spacing-md);
}

.post-meta-detailed {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  align-items: center;
  font-size: 0.875rem;
  opacity: 0.95;
}

.meta-separator {
  opacity: 0.5;
}

.post-content {
  font-size: 1.125rem;
  line-height: 1.75;
  margin-bottom: var(--spacing-xl);
}

.post-content h1,
.post-content h2,
.post-content h3,
.post-content h4,
.post-content h5,
.post-content h6 {
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-md);
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-text);
}

.post-content h1 {
  font-size: 2rem;
}

.post-content h2 {
  font-size: 1.75rem;
}

.post-content h3 {
  font-size: 1.5rem;
}

.post-content h4 {
  font-size: 1.25rem;
}

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

.post-content a {
  color: var(--color-primary);
  text-decoration: underline;
  transition: color 0.2s;
}

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

.post-content ul,
.post-content ol {
  margin-bottom: var(--spacing-md);
  padding-left: var(--spacing-lg);
}

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

.post-content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background-color: var(--color-bg-tertiary);
  padding: 0.125rem 0.375rem;
  border-radius: var(--radius-sm);
  color: var(--color-text);
}

.post-content pre {
  background-color: var(--color-code-bg);
  color: #e2e8f0;
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--spacing-md);
  font-size: 0.875rem;
  line-height: 1.6;
}

.post-content pre code {
  background: none;
  padding: 0;
  color: inherit;
  font-size: inherit;
}

.post-content blockquote {
  border-left: 4px solid var(--color-primary);
  padding-left: var(--spacing-md);
  margin: var(--spacing-lg) 0;
  font-style: italic;
  color: var(--color-text-light);
}

.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  margin: var(--spacing-lg) 0;
}

.post-footer {
  border-top: 2px solid var(--color-border);
  padding-top: var(--spacing-xl);
  margin-top: var(--spacing-xl);
}

.post-share {
  margin-bottom: var(--spacing-xl);
}

.post-share h3 {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-md);
}

.share-buttons {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.share-btn {
  padding: 0.625rem 1.25rem;
  border-radius: var(--radius-md);
  text-decoration: none;
  font-weight: 600;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.share-btn.twitter {
  background-color: #1da1f2;
  color: white;
}

.share-btn.twitter:hover {
  background-color: #0d8cd9;
}

.share-btn.linkedin {
  background-color: #0077b5;
  color: white;
}

.share-btn.linkedin:hover {
  background-color: #006399;
}

.related-posts {
  margin-bottom: var(--spacing-xl);
}

.related-posts h3 {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-md);
}

.related-posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-md);
}

.related-post-card {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.2s;
  display: block;
}

.related-post-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
}

.related-post-title {
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  color: var(--color-text);
}

.related-post-date {
  font-size: 0.875rem;
  color: var(--color-text-light);
}

.comments-section {
  margin-top: var(--spacing-xl);
}

.comments-section h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-lg);
}

.comment-form-wrapper {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.comment-form-wrapper h4 {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
}

.comment-form .form-group {
  margin-bottom: var(--spacing-md);
}

.comment-form label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  font-size: 0.875rem;
}

.comment-form input,
.comment-form textarea {
  width: 100%;
  padding: 0.625rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: 1rem;
  transition: border-color 0.2s;
}

.comment-form input:focus,
.comment-form textarea:focus {
  outline: none;
  border-color: var(--color-primary);
}

.comment-form textarea {
  resize: vertical;
}

.btn-submit {
  background-color: var(--color-primary);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
  font-size: 1rem;
}

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

.btn-submit:disabled {
  background-color: var(--color-text-light);
  cursor: not-allowed;
}

.form-note {
  margin-top: var(--spacing-sm);
  font-size: 0.875rem;
  color: var(--color-text-light);
}

.comment-message {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  display: none;
}

.comment-message.success {
  background-color: #d1fae5;
  color: #065f46;
  display: block;
}

.comment-message.error {
  background-color: #fee2e2;
  color: #991b1b;
  display: block;
}

.comments-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.comment-item {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
}

.comment-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-sm);
}

.comment-author {
  font-weight: 600;
  color: var(--color-text);
}

.comment-date {
  font-size: 0.875rem;
  color: var(--color-text-light);
}

.comment-content {
  color: var(--color-text);
  line-height: 1.6;
}

.loading-spinner {
  text-align: center;
  padding: var(--spacing-lg);
  color: var(--color-text-light);
}

.page-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: var(--spacing-2xl) 0;
  margin-bottom: var(--spacing-xl);
}

.page-title {
  font-size: 2.5rem;
  font-weight: 700;
  color: white;
}

.page-content {
  font-size: 1.125rem;
  line-height: 1.75;
  margin-bottom: var(--spacing-xl);
}

.page-content h1,
.page-content h2,
.page-content h3 {
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  font-weight: 700;
}

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

.page-content a {
  color: var(--color-primary);
  text-decoration: underline;
}

.site-footer {
  background-color: var(--color-text);
  color: white;
  padding: var(--spacing-2xl) 0 var(--spacing-lg);
  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-xl);
}

.footer-section h3 {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
  font-weight: 600;
}

.footer-section p {
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.6;
}

.footer-section a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  display: block;
  margin-bottom: var(--spacing-xs);
  transition: color 0.2s;
}

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

.social-links {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-md);
  text-align: center;
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.875rem;
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .header-content {
    flex-direction: column;
    align-items: flex-start;
  }

  .main-nav {
    width: 100%;
    justify-content: space-between;
  }

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

  .section-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .post-header .post-title {
    font-size: 2rem;
  }

  .related-posts-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.5rem;
  }

  .post-header .post-title {
    font-size: 1.5rem;
  }

  .post-content {
    font-size: 1rem;
  }
}