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

:root {
  /* Colors */
  --primary-color: #007bff;
  --secondary-color: #6c757d;
  --accent-color: #28a745;
  --text-color: #212529;
  --text-light: #6c757d;
  --bg-color: #ffffff;
  --bg-alt: #f8f9fa;
  --border-color: #dee2e6;

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-family-mono: SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  --font-size-base: 16px;
  --line-height-base: 1.6;

  /* Search Styles */
  --search-bg: #ffffff;
  --search-border: #ddd;
  --search-focus: #666;
  
  /* 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: 2px;
  --radius-md: 4px;
  --radius-lg: 6px;
  
  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
}

/* Month Group Styles */
.month-group {
  margin-bottom: 2.5rem;
}

.month-title {
  font-size: 1.25rem;
  color: var(--secondary-color);
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border-color);
}

/* Search Styles */
.post-preview {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-top: 0.5rem;
  margin-bottom: 1rem;
  line-height: 1.4;
}

.search-highlight {
  background-color: #fff3cd;
  padding: 0.1rem 0.2rem;
  border-radius: 2px;
}

.search-container {
  margin-bottom: 2rem;
}

#search-input {
  width: 100%;
  padding: 0.8rem;
  font-size: 1rem;
  border: 2px solid var(--search-border);
  border-radius: var(--radius-md);
  background-color: var(--search-bg);
  transition: border-color 0.3s ease;
}

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

/* Theme support: default light, override with [data-theme="dark"] */
:root[data-theme="dark"], [data-theme="dark"] {
  --primary-color: #4ea8ff;
  --secondary-color: #adb5bd;
  --accent-color: #66d19e;
  --text-color: #e9ecef;
  --text-light: #ced4da;
  --bg-color: #0f1720;
  --bg-alt: #0b1220;
  --border-color: rgba(255,255,255,0.06);
}

html {
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  color: var(--text-color);
  background-color: var(--bg-color);
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 500;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

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

/* Article / post content typography: increase font size for better readability */
.post-content {
  font-size: 1.125rem; /* ~18px assuming base 16px */
  line-height: 1.8;    /* slightly more airy for Chinese text */
}

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

a:hover {
  color: #0056b3;
  text-decoration: underline;
}

/* Layout */
.site-header {
  background: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md) var(--spacing-lg);
}

.nav-brand a {
  font-size: 1.5rem;
  font-weight: 500;
  color: var(--text-color);
  text-decoration: none;
}

.nav-brand a:hover {
  text-decoration: none;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
}

/* Mobile menu styles */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  width: 30px;
  height: 24px;
  position: relative;
  z-index: 1001;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--text-color);
  margin: 5px 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

@media (max-width: 768px) {
  .hamburger {
    display: block;
  }

  .nav-menu {
    display: flex;
    visibility: hidden;
    opacity: 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--bg-color);
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    padding-top: 80px;
    gap: var(--spacing-lg);
    transition: visibility 0.3s ease, opacity 0.3s ease;
  }

  .nav-menu.active {
    visibility: visible;
    opacity: 1;
  }

  .nav-menu .nav-item {
    margin: var(--spacing-sm) 0;
  }

  .nav-menu .nav-link {
    font-size: 1.2rem;
    color: var(--text-color);
    text-decoration: none;
  }
    gap: var(--spacing-lg);
    z-index: 1000;
    padding-top: 80px;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
  }

  .nav-menu.active {
    opacity: 1;
    visibility: visible;
    display: flex;
  }

  .hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .hamburger.active span:nth-child(2) {
    opacity: 0;
  }

  .hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
  }
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 1rem;
}

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

.nav-link {
  color: var(--text-color);
  font-weight: 400;
  text-decoration: none;
}

.nav-link:hover {
  color: var(--primary-color);
  text-decoration: none;
}

.main {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-lg);
  min-height: calc(100vh - 200px);
}

@media (max-width: 768px) {
  .main {
    padding: var(--spacing-md) var(--spacing-md);
  }
  
  .content-wrapper {
    flex-direction: column;
  }

  .content-main {
    width: 100%;
  }

  .wechat-qr-sidebar {
    position: static;
    width: 100%;
    margin-top: var(--spacing-xl);
    padding: var(--spacing-md);
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .post-content {
    font-size: 1rem;
  }
  
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.5rem; }
  h4 { font-size: 1.25rem; }
  h5 { font-size: 1.1rem; }
  h6 { font-size: 1rem; }
}

/* Home Page */
.hero {
  text-align: center;
  padding: var(--spacing-xl) 0;
  margin: 0 0 var(--spacing-xl) 0;
  /* 移除底部边框，解决横线问题 */
}

.hero-title {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
}

.hero-subtitle {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-light);
}

.hero-description {
  font-size: 1rem;
  max-width: 600px;
  margin: 0 auto;
  color: var(--text-light);
}

/* Homepage center message - 修改为更合适的样式 */
.homepage-message {
  text-align: center;
  margin-top: calc(var(--spacing-xl) * -1); /* 抵消.hero的margin-bottom */
  padding: var(--spacing-xxl) 0;
}

.homepage-text {
  font-size: 1.5rem;
  color: var(--text-color);
  max-width: 900px;
  margin: 0 auto;
  font-weight: 500;
}

/* Giscus / comments wrapper styling to integrate with theme */
.post-comments {
  margin-top: var(--spacing-xl);
  padding: var(--spacing-lg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: var(--bg-alt);
}

#giscus-comments,
.giscus-frame {
  width: 100% !important;
}

.recent-posts {
  margin-top: var(--spacing-xxl);
}

.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

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

.post-card:hover {
  box-shadow: var(--shadow-md);
}

.post-title {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-sm);
}

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

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

.post-meta {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: var(--spacing-sm);
}

.post-summary {
  color: var(--text-light);
  line-height: 1.5;
}

.view-all {
  text-align: center;
  margin-top: var(--spacing-xl);
}

.btn {
  display: inline-block;
  background: var(--primary-color);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 400;
  text-decoration: none;
  border: none;
  cursor: pointer;
}

.btn:hover {
  background: #0056b3;
  color: white;
  text-decoration: none;
}

/* Post Page */
.post {
  /* Constrain the article width so content and comments align */
  margin: 0 auto;
  max-width: 760px; /* comfortable readable measure */
  width: 100%;
  box-sizing: border-box;
}

.post-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-lg);
  border-bottom: 1px solid var(--border-color);
}

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

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

.post-meta-primary {
  margin-bottom: var(--spacing-sm);
}

.post-meta-primary time,
.post-meta-primary .post-reading-time,
.post-meta-primary .post-word-count {
  margin-right: var(--spacing-md);
}

.post-meta-secondary {
  border-top: 1px solid var(--border-color);
  padding-top: var(--spacing-sm);
}

.post-categories,
.post-tags {
  margin-right: var(--spacing-md);
}

.post-categories a,
.post-tags a {
  background: var(--bg-alt);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  margin-right: var(--spacing-xs);
  font-size: 0.75rem;
  text-decoration: none;
}

.post-categories a:hover,
.post-tags a:hover {
  background: #e9ecef;
  text-decoration: none;
}

.post-content {
  line-height: 1.7;
}

.post-content h2 {
  margin-top: var(--spacing-xl);
  padding-bottom: var(--spacing-sm);
  border-bottom: 1px solid var(--border-color);
}

.post-content h3 {
  margin-top: var(--spacing-lg);
}

.post-content code {
  background: var(--bg-alt);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-family: var(--font-family-mono);
  font-size: 0.875rem;
}

.post-content pre {
  background: var(--bg-alt);
  padding: var(--spacing-lg);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: var(--spacing-lg) 0;
}

.post-content pre code {
  background: none;
  padding: 0;
}

.post-content blockquote {
  border-left: 3px solid var(--primary-color);
  padding-left: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
  color: var(--text-light);
  font-style: italic;
}

.post-footer {
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--border-color);
}

/* Ensure comments area aligns with the post content and the giscus iframe respects container width */
.post-comments {
  box-sizing: border-box;
  max-width: 100%;
  width: 100%;
  padding: var(--spacing-lg);
}

#giscus-comments,
.post-comments .giscus-frame,
.post-comments iframe {
  width: 100% !important;
  max-width: 100% !important;
  box-sizing: border-box !important;
}

/* Footer */
.site-footer {
  background: var(--bg-alt);
  padding: var(--spacing-xl) var(--spacing-lg);
  text-align: center;
  margin-top: var(--spacing-xxl);
  border-top: 1px solid var(--border-color);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
}

.social-links {
  margin-top: var(--spacing-md);
}

.social-links a {
  margin: 0 var(--spacing-sm);
  color: var(--text-light);
  text-decoration: none;
}

.social-links a:hover {
  color: var(--primary-color);
  text-decoration: none;
}

/* Content Layout with QR Code */
.content-wrapper {
  display: flex;
  gap: var(--spacing-xl);
  align-items: flex-start;
}

.content-main {
  flex: 1;
  min-width: 0; /* Prevent flex item from overflowing */
}

.wechat-qr-sidebar {
  width: 280px;
  flex-shrink: 0;
  position: sticky;
  top: 100px;
}

.qr-container {
  background: var(--bg-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.qr-image {
  width: 100%;
  max-width: 200px;
  height: auto;
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-md);
}

.qr-text {
  color: var(--text-light);
  font-size: 0.875rem;
  margin: 0;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .nav-menu {
    gap: var(--spacing-md);
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1.125rem;
  }
  
  .posts-grid {
    grid-template-columns: 1fr;
  }
  
  .post-title {
    font-size: 1.5rem;
  }
  
  .main {
    padding: var(--spacing-lg) var(--spacing-md);
  }
  
  /* Mobile QR Code Layout */
  .content-wrapper {
    flex-direction: column;
    gap: var(--spacing-lg);
  }
  
  .wechat-qr-sidebar {
    width: 100%;
    position: static;
    order: 2;
  }
  
  .qr-container {
    max-width: 250px;
    margin: 0 auto;
  }
}

/* Code Highlighting */
.highlight {
  border-radius: var(--radius-md);
  margin: var(--spacing-lg) 0;
}

.highlight pre {
  margin: 0;
  padding: var(--spacing-lg);
}

/* Reading Progress */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--border-color);
  z-index: 1001;
}

.reading-progress-bar {
  height: 100%;
  background: var(--primary-color);
  width: 0%;
  transition: width 0.1s ease;
}