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

:root {
  --primary-color: #2563eb;
  --text-color: #1f2937;
  --bg-color: #ffffff;
  --secondary-bg: #f3f4f6;
  --border-color: #e5e7eb;
  --max-width: 800px;
  --spacing: 1.5rem;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.7;
  color: var(--text-color);
  background: var(--bg-color);
}

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

/* Navigation */
.navbar {
  background: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.nav-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

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

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

/* Main Content */
.main {
  min-height: calc(100vh - 200px);
  padding: 3rem 0;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  margin-bottom: 1rem;
  color: var(--text-color);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; margin-top: 2rem; }
h3 { font-size: 1.5rem; margin-top: 1.5rem; }

p {
  margin-bottom: 1.5rem;
}

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

a:hover {
  text-decoration: underline;
}

/* Post Styles */
.post-header {
  text-align: center;
  margin-bottom: 3rem;
}

.post-header h1 {
  margin-bottom: 0.5rem;
}

.post-meta {
  color: #6b7280;
  font-size: 0.9rem;
}

.separator {
  margin: 0 0.5rem;
}

.post-tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 1rem;
}

.tag {
  background: var(--secondary-bg);
  padding: 0.5rem 1rem;
  border-radius: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-color);
  text-decoration: none;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}

.tag:hover {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
  text-decoration: none;
}

/* Tag button when it's a button element (for filters) */
button.tag {
  background: var(--secondary-bg);
  border: 2px solid var(--border-color);
  font-family: inherit;
}

button.tag:hover {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
}

button.tag.tag-selected {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
}

.post-content {
  max-width: 720px;
  margin: 0 auto;
}

.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: 0.5rem;
  margin: 2rem 0;
}

.post-content pre {
  background: var(--secondary-bg);
  padding: 1.5rem;
  border-radius: 0.5rem;
  overflow-x: auto;
  margin: 2rem 0;
}

.post-content code {
  font-family: 'Monaco', 'Menlo', monospace;
  font-size: 0.9em;
}

.post-content p code {
  background: var(--secondary-bg);
  padding: 0.2rem 0.4rem;
  border-radius: 0.25rem;
}

.post-content blockquote {
  border-left: 4px solid var(--primary-color);
  padding-left: 1.5rem;
  margin: 2rem 0;
  font-style: italic;
  color: #6b7280;
}

.post-content ul, .post-content ol {
  margin-left: 2rem;
  margin-bottom: 1.5rem;
}

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

/* Post Layout with Sidebar */
.post-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  margin-top: 3rem;
}

@media (min-width: 1024px) {
  .post {
    max-width: none;
  }
  
  .post .container {
    max-width: 1400px;
  }
  
  .post-layout {
    grid-template-columns: minmax(200px, 1fr) minmax(600px, 3fr);
    gap: 4rem;
  }
  
  .post-sidebar {
    order: 1;
  }
  
  .post-main {
    order: 2;
    max-width: 800px;
  }
}

/* Table of Contents */
.post-sidebar .table-of-contents {
  background: var(--secondary-bg);
  padding: 1.5rem;
  border-radius: 0.5rem;
  position: sticky;
  top: 80px;
  max-height: calc(100vh - 100px);
  overflow-y: auto;
}

@media (max-width: 1023px) {
  .post-sidebar .table-of-contents {
    position: static;
    margin-bottom: 2rem;
  }
}

.table-of-contents h2 {
  font-size: 1.1rem;
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.table-of-contents .toc-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.table-of-contents .toc-nav li {
  margin-bottom: 0.5rem;
}

.table-of-contents .toc-level-2 {
  margin-left: 0;
}

.table-of-contents .toc-level-3 {
  margin-left: 1rem;
  font-size: 0.9rem;
}

.table-of-contents .toc-level-4 {
  margin-left: 2rem;
  font-size: 0.85rem;
}

.table-of-contents a {
  color: var(--text-color);
  text-decoration: none;
  display: block;
  padding: 0.25rem 0;
  transition: all 0.2s ease;
  border-left: 2px solid transparent;
  padding-left: 0.5rem;
  margin-left: -0.5rem;
}

.table-of-contents a:hover {
  color: var(--primary-color);
  border-left-color: var(--primary-color);
}

.table-of-contents a.active {
  color: var(--primary-color);
  border-left-color: var(--primary-color);
  font-weight: 600;
}

/* Blog Index */
.page-header {
  text-align: center;
  margin-bottom: 3rem;
}

.page-description {
  color: #6b7280;
  font-size: 1.1rem;
}

.posts-list {
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

.post-preview {
  padding-bottom: 3rem;
  border-bottom: 1px solid var(--border-color);
}

.post-preview:last-child {
  border-bottom: none;
}

.post-preview h2 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.post-preview h2 a {
  color: var(--text-color);
  text-decoration: none;
}

.post-preview h2 a:hover {
  color: var(--primary-color);
}

.post-excerpt {
  color: #6b7280;
  margin: 1rem 0;
}

.read-more {
  color: var(--primary-color);
  font-weight: 600;
}

/* Search */
.search-input {
  width: 100%;
  padding: 1rem;
  font-size: 1.1rem;
  border: 2px solid var(--border-color);
  border-radius: 0.5rem;
  margin-bottom: 1.5rem;
}

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

.tag-filters {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

.search-results {
  margin-top: 2rem;
}

.search-hint {
  text-align: center;
  color: #6b7280;
  font-style: italic;
}

.search-result-item {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--border-color);
}

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

/* Footer */
.footer {
  background: var(--secondary-bg);
  padding: 2rem 0;
  margin-top: 4rem;
  text-align: center;
  color: #6b7280;
}

.social-links {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  margin: 1rem 0;
}

.social-links a {
  color: #6b7280;
}

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

/* Post Navigation (Previous/Next) */
.post-navigation {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 2px solid var(--border-color);
}

.post-nav-prev,
.post-nav-next {
  display: flex;
  flex-direction: column;
  padding: 1.5rem;
  background: var(--secondary-bg);
  border-radius: 0.5rem;
  text-decoration: none;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.post-nav-prev:hover,
.post-nav-next:hover {
  background: var(--bg-color);
  border-color: var(--primary-color);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.post-nav-next {
  text-align: right;
}

.post-nav-label {
  font-size: 0.85rem;
  color: #6b7280;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.post-nav-title {
  color: var(--text-color);
  font-weight: 600;
  font-size: 1rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  text-overflow: ellipsis;
}

.post-nav-prev:hover .post-nav-title,
.post-nav-next:hover .post-nav-title {
  color: var(--primary-color);
}

@media (max-width: 768px) {
  .post-navigation {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .post-nav-next {
    text-align: left;
  }
}

.post-footer {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.share-buttons {
  display: flex;
  gap: 1rem;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

.share-buttons a {
  padding: 0.5rem 1rem;
  background: var(--secondary-bg);
  border-radius: 0.25rem;
  text-decoration: none;
  color: var(--text-color);
  transition: all 0.2s ease;
}

.share-buttons a:hover {
  background: var(--primary-color);
  color: white;
}

/* Copy Button for Code Blocks */
.post-content pre {
  position: relative;
}

.copy-button {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  padding: 0.5rem 0.75rem;
  background: rgba(0, 0, 0, 0.6);
  color: white;
  border: none;
  border-radius: 0.25rem;
  font-size: 0.85rem;
  cursor: pointer;
  opacity: 0;
  transition: all 0.2s ease;
  font-family: inherit;
  font-weight: 500;
}

.post-content pre:hover .copy-button {
  opacity: 1;
}

.copy-button:hover {
  background: rgba(0, 0, 0, 0.8);
  transform: scale(1.05);
}

.copy-button:active {
  transform: scale(0.95);
}

[data-theme="dark"] .copy-button {
  background: rgba(255, 255, 255, 0.2);
}

[data-theme="dark"] .copy-button:hover {
  background: rgba(255, 255, 255, 0.3);
}

/* Responsive */
@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  h3 { font-size: 1.25rem; }
  
  .nav-menu {
    gap: 1rem;
  }
  
  .navbar .container {
    flex-direction: column;
    gap: 1rem;
  }
  
  .post-header {
    text-align: left;
  }
  
  .post-tags {
    justify-content: flex-start;
  }
}


/* Dark Mode */
[data-theme="dark"] {
  --primary-color: #60a5fa;
  --text-color: #e5e7eb;
  --bg-color: #111827;
  --secondary-bg: #1f2937;
  --border-color: #374151;
}

/* Smooth Transitions */
body, .navbar, .nav-menu a, .tag, .post-preview, .nav-brand {
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

/* Dark Mode Toggle */
.dark-mode-toggle {
  background: none;
  border: 2px solid var(--border-color);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  transition: all 0.3s ease;
  margin-left: 1rem;
}

.dark-mode-toggle:hover {
  transform: rotate(20deg) scale(1.1);
  border-color: var(--primary-color);
}

.nav-menu {
  display: flex;
  align-items: center;
}

/* Smooth Scroll */
html {
  scroll-behavior: smooth;
}

/* Fade In Animation */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.post-preview, .page-content > *, .post-content > * {
  animation: fadeIn 0.6s ease-out;
}

/* Hover Effects */
.post-preview {
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.post-preview:hover {
  transform: translateY(-2px);
}

.read-more, .tag {
  transition: all 0.2s ease;
}

.read-more:hover {
  transform: translateX(4px);
}


/* Link Underline Animation */
.post-content a, .page-content a {
  position: relative;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: border-color 0.3s ease;
}

.post-content a:hover, .page-content a:hover {
  border-bottom-color: var(--primary-color);
}

/* Loading State */
body.loading {
  opacity: 0;
}

body {
  opacity: 1;
  transition: opacity 0.3s ease;
}