/* Import Fonts */
@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');
@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600&display=swap');

/* CSS Variables - Elevated Editorial Design */
:root {
  /* Light Mode - Warm Editorial Palette */
  --bg-primary: #FEFEFE;
  --bg-secondary: #F8F9FA;
  --bg-tertiary: #F1F3F5;

  --text-primary: #1A1A1A;
  --text-secondary: #4A4A4A;
  --text-tertiary: #666666;

  --accent: #FF6B6B;
  --accent-hover: #FF5252;
  --accent-soft: rgba(255, 107, 107, 0.1);

  --border-light: #E8E8E8;
  --border-medium: #D4D4D4;

  --card-bg: #FFFFFF;
  --card-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04), 0 1px 4px rgba(0, 0, 0, 0.04);
  --card-shadow-md: 0 4px 6px rgba(0, 0, 0, 0.05), 0 2px 4px rgba(0, 0, 0, 0.03);
  --card-shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.08), 0 3px 6px rgba(0, 0, 0, 0.04);

  --code-bg: #2E3440;
  --code-text: #D8DEE9;

  --gradient-bar: linear-gradient(90deg, #FF6B6B 0%, #FF8E53 100%);
  --header-bg: rgba(254, 254, 254, 0.85);

  --transition-base: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.dark {
  /* Dark Mode - Deep Slate Palette */
  --bg-primary: #0F1419;
  --bg-secondary: #1A1F29;
  --bg-tertiary: #242B38;

  --text-primary: #F0F0F0;
  --text-secondary: #B8B8B8;
  --text-tertiary: #8A8A8A;

  --accent: #FF8A80;
  --accent-hover: #FFA294;
  --accent-soft: rgba(255, 138, 128, 0.15);

  --border-light: #2A2F3A;
  --border-medium: #3A404D;

  --card-bg: #1A1F29;
  --card-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2), 0 1px 4px rgba(0, 0, 0, 0.2);
  --card-shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3), 0 2px 4px rgba(0, 0, 0, 0.2);
  --card-shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.4), 0 3px 6px rgba(0, 0, 0, 0.3);

  --code-bg: #1E2430;
  --code-text: #D8DEE9;

  --gradient-bar: linear-gradient(90deg, #FF8A80 0%, #FFB380 100%);
  --header-bg: rgba(15, 20, 25, 0.85);
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Gradient Bar */
.gradient-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient-bar);
  z-index: 1001;
}

/* Reading Progress */
.reading-progress {
  position: fixed;
  top: 2px;
  left: 0;
  height: 2px;
  background: var(--accent);
  z-index: 1002;
  width: 0;
  transition: width 0.1s ease-out;
}

/* Header */
.site-header {
  position: sticky;
  top: 2px;
  background: var(--header-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  z-index: 100;
  transition: all var(--transition-base);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 2rem;
}

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

.site-logo {
  font-size: 1.125rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

.site-logo:hover {
  color: var(--accent);
  text-decoration: none;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
  align-items: center;
  margin: 0;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9375rem;
  font-weight: 500;
  transition: color var(--transition-base);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--transition-base);
}

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

.nav-link:hover::after {
  width: 100%;
}

/* Nav Actions */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.search-toggle,
.theme-toggle {
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  transition: all var(--transition-base);
}

.search-toggle:hover,
.theme-toggle:hover {
  color: var(--text-primary);
  background: var(--bg-secondary);
}

.search-toggle:focus-visible,
.theme-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.search-toggle svg,
.theme-toggle svg {
  width: 18px;
  height: 18px;
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text-secondary);
}

.hamburger {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
  transition: all var(--transition-base);
  border-radius: 2px;
}

.mobile-menu-btn.active .hamburger span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

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

.mobile-menu-btn.active .hamburger span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.mobile-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border-light);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: var(--card-shadow-md);
}

.mobile-menu.active {
  display: block;
}

.mobile-nav-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.mobile-nav-link {
  display: block;
  padding: 1rem 2rem;
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: 1px solid var(--border-light);
  font-weight: 500;
  transition: all var(--transition-base);
}

.mobile-nav-link:hover {
  background: var(--bg-secondary);
  color: var(--accent);
  text-decoration: none;
}

.mobile-nav-list li:last-child .mobile-nav-link {
  border-bottom: none;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Hero Section */
.hero {
  padding: 6rem 0 4rem;
  text-align: center;
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 900;
  letter-spacing: -0.04em;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  background: var(--gradient-bar);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1.125rem, 2vw, 1.375rem);
  color: var(--text-secondary);
  max-width: 660px;
  margin: 0 auto;
  font-weight: 400;
  line-height: 1.6;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.25;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; margin-top: 3rem; }
h3 { font-size: 1.5rem; margin-top: 2rem; }
h4 { font-size: 1.25rem; margin-top: 1.5rem; }

p {
  margin-bottom: 1.5rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--accent-hover);
}

/* Section Styles */
.series-section,
.quick-start,
.recent-posts {
  padding: 4rem 0;
  border-top: 1px solid var(--border-light);
}

.section-title {
  font-size: 1.875rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 2rem;
  color: var(--text-primary);
}

/* Series Grid */
.series-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.series-card {
  display: block;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: 12px;
  padding: 2rem;
  text-decoration: none;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.series-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--accent);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--transition-slow);
}

.series-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--card-shadow-lg);
  border-color: var(--border-medium);
  text-decoration: none;
}

.series-card:hover::before {
  transform: scaleY(1);
}

.series-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.series-card-count {
  font-size: 0.9375rem;
  color: var(--text-tertiary);
  font-weight: 500;
}

/* Quick Start Grid */
.quick-start-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.quick-start-card {
  display: block;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: 12px;
  padding: 2rem;
  text-decoration: none;
  transition: all var(--transition-base);
  position: relative;
}

.quick-start-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--accent-soft);
  opacity: 0;
  transition: opacity var(--transition-base);
  border-radius: 12px;
  pointer-events: none;
}

.quick-start-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--card-shadow-lg);
  border-color: var(--accent);
  text-decoration: none;
}

.quick-start-card:hover::after {
  opacity: 1;
}

.quick-start-icon {
  width: 48px;
  height: 48px;
  background: var(--accent-soft);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
  position: relative;
  z-index: 1;
}

.quick-start-icon svg {
  width: 24px;
  height: 24px;
  color: var(--accent);
}

.quick-start-card-title {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  position: relative;
  z-index: 1;
}

.quick-start-card-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0;
  position: relative;
  z-index: 1;
}

/* Post Cards */
.posts-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 2rem;
}

.post-card {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: 12px;
  padding: 2rem;
  transition: all var(--transition-base);
  position: relative;
}

.post-card::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--accent);
  border-radius: 12px 0 0 12px;
  opacity: 0;
  transition: opacity var(--transition-base);
}

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

.post-card:hover::before {
  opacity: 1;
}

.post-card-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.post-card-title a {
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

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

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.875rem;
  color: var(--text-tertiary);
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.post-date {
  font-weight: 500;
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all var(--transition-base);
}

.tag:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
  transform: translateY(-1px);
}

.post-summary {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1rem;
}

.read-more {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.9375rem;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: gap var(--transition-base);
}

.read-more::after {
  content: '→';
  transition: transform var(--transition-base);
}

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

/* View All */
.view-all {
  text-align: center;
  margin-top: 2.5rem;
}

.view-all-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  font-weight: 600;
  text-decoration: none;
  transition: gap var(--transition-base);
}

.view-all-link:hover {
  gap: 0.75rem;
}

/* Single Post Page */
.post-single {
  max-width: 740px;
  margin: 0 auto;
  padding: 4rem 2rem;
}

.post-header {
  margin-bottom: 3rem;
}

.post-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 900;
  letter-spacing: -0.04em;
  line-height: 1.3;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
  word-break: keep-all;
}

.title-main {
  display: block;
}

.title-sub {
  display: block;
  font-size: 0.55em;
  font-weight: 500;
  color: var(--text-secondary);
  margin-top: 0.4rem;
  letter-spacing: -0.01em;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding-bottom: 1.5rem;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-light);
  font-size: 0.9375rem;
  color: var(--text-tertiary);
  font-weight: 500;
}

.reading-time::before {
  content: '•';
  margin-right: 1rem;
}

/* Post Content Prose */
.post-content {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--text-primary);
}

.post-content > * + * {
  margin-top: 1.5rem;
}

.post-content h2 {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-light);
}

.post-content ul,
.post-content ol {
  padding-left: 1.5rem;
}

.post-content li {
  margin-bottom: 0.75rem;
}

.post-content li > ul,
.post-content li > ol {
  margin-top: 0.75rem;
}

.post-content a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: all var(--transition-base);
}

.post-content a:hover {
  color: var(--accent-hover);
  text-decoration-thickness: 2px;
}

/* Table of Contents */
.toc {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 2rem 0 3rem;
}

.toc-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.toc-list {
  list-style: none;
  padding: 0;
}

.toc-list li {
  margin-bottom: 0.5rem;
}

.toc-link {
  display: block;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 0.25rem 0;
  padding-left: 1rem;
  border-left: 2px solid transparent;
  margin-left: -1rem;
  transition: all var(--transition-base);
  font-size: 0.9375rem;
}

.toc-link:hover {
  color: var(--text-primary);
  border-left-color: var(--border-medium);
}

.toc-link.active {
  color: var(--accent);
  border-left-color: var(--accent);
  font-weight: 600;
}

/* Code Blocks */
pre {
  background: var(--code-bg);
  border: 1px solid var(--border-light);
  border-radius: 10px;
  padding: 1.5rem;
  padding-top: 3rem;
  overflow-x: auto;
  position: relative;
  margin: 2rem 0;
  box-shadow: var(--card-shadow-sm);
}

pre::before {
  content: '';
  position: absolute;
  top: 12px;
  left: 16px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #FF5F56;
  box-shadow:
    20px 0 0 #FFBD2E,
    40px 0 0 #27C93F;
}

.code-lang-label {
  position: absolute;
  top: 10px;
  left: 80px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-family: 'JetBrains Mono', monospace;
}

pre code {
  background: transparent;
  border: none;
  padding: 0;
  color: var(--code-text);
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.875rem;
  line-height: 1.7;
}

code {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  padding: 0.2em 0.4em;
  border-radius: 4px;
  font-size: 0.875em;
  font-family: 'JetBrains Mono', monospace;
  color: var(--text-primary);
  font-weight: 500;
}

.copy-code-btn {
  position: absolute;
  top: 10px;
  right: 12px;
  background: var(--accent);
  color: white;
  border: none;
  padding: 0.4rem 0.75rem;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  opacity: 0;
  transition: all var(--transition-base);
}

pre:hover .copy-code-btn {
  opacity: 1;
}

.copy-code-btn:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.copy-code-btn.copied {
  background: #27C93F;
}

/* Blockquote */
blockquote {
  border-left: 3px solid var(--accent);
  background: var(--bg-secondary);
  padding: 1.5rem 2rem;
  margin: 2rem 0;
  border-radius: 0 8px 8px 0;
  color: var(--text-secondary);
  font-style: italic;
}

blockquote p:last-child {
  margin-bottom: 0;
}

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  border: 1px solid var(--border-light);
  border-radius: 8px;
  overflow: hidden;
}

thead {
  background: var(--bg-secondary);
}

th {
  padding: 0.875rem 1rem;
  text-align: left;
  font-weight: 700;
  font-size: 0.9375rem;
  border-bottom: 2px solid var(--border-medium);
}

td {
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--border-light);
}

tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: var(--bg-secondary);
}

/* Images */
article img {
  max-width: 100%;
  height: auto;
  border-radius: 10px;
  margin: 2rem 0;
  box-shadow: var(--card-shadow-md);
}

/* Series Navigation */
.series-nav {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 2rem 0 3rem;
}

.series-nav-title {
  font-size: 0.875rem;
  font-weight: 600;
  margin: 0 0 1.25rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.series-nav-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.series-nav-item {
  position: relative;
  margin-bottom: 0.5rem;
}

.series-nav-link {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 0.5rem 0 0.5rem 1rem;
  border-left: 2px solid transparent;
  transition: all var(--transition-base);
  font-size: 0.9375rem;
  line-height: 1.5;
}

.series-nav-link:hover {
  color: var(--text-primary);
  border-left-color: var(--border-medium);
  background: var(--bg-tertiary);
}

.series-nav-number {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-tertiary);
  min-width: 1.75rem;
  opacity: 0.6;
  transition: opacity var(--transition-base);
}

.series-nav-link:hover .series-nav-number {
  opacity: 0.9;
}

.series-nav-item.current .series-nav-link {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-soft);
  font-weight: 600;
}

.series-nav-item.current .series-nav-number {
  color: var(--accent);
  opacity: 1;
}

/* Post Feedback */
.post-feedback {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin: 3rem 0 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-light);
}

.feedback-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1.4rem;
  border: 1px solid var(--border-light);
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.2s ease;
}

.feedback-link:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

button.feedback-link {
  font-family: inherit;
  background: transparent;
}

/* Print styles for PDF download */
@media print {
  .site-header,
  .gradient-bar,
  .reading-progress,
  .series-nav,
  .toc,
  .post-feedback,
  .post-navigation,
  .site-footer,
  .search-overlay,
  .copy-code-btn,
  .code-lang-label {
    display: none !important;
  }

  :root, .dark {
    --bg-primary: #fff;
    --bg-secondary: #f5f5f5;
    --text-primary: #000;
    --text-secondary: #333;
    --text-tertiary: #555;
    --border-light: #ccc;
    --code-bg: #f5f5f5;
    --code-text: #333;
  }

  body {
    background: white;
    color: black;
    font-size: 12pt;
  }

  .post-single {
    max-width: 100%;
    padding: 0;
  }

  pre {
    white-space: pre-wrap;
    word-wrap: break-word;
    border: 1px solid #ccc;
    box-shadow: none;
  }

  a {
    color: #333;
    text-decoration: underline;
  }
}

/* Post Navigation */
.post-navigation {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  margin-top: 4rem;
  padding-top: 3rem;
  border-top: 1px solid var(--border-light);
}

.nav-prev,
.nav-next {
  display: block;
  padding: 1.5rem;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: 10px;
  text-decoration: none;
  transition: all var(--transition-base);
}

.nav-prev:hover,
.nav-next:hover {
  transform: translateY(-2px);
  box-shadow: var(--card-shadow-md);
  border-color: var(--accent);
  text-decoration: none;
}

.nav-label {
  display: block;
  font-size: 0.8125rem;
  color: var(--text-tertiary);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.nav-title {
  display: block;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  margin-top: 3rem;
}

.pagination a,
.pagination span {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 1rem;
  border: 1px solid var(--border-light);
  border-radius: 8px;
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 500;
  transition: all var(--transition-base);
}

.pagination a:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
  transform: translateY(-2px);
}

.pagination .disabled {
  opacity: 0.4;
  pointer-events: none;
}

/* List Page */
.list-page {
  padding: 3rem 0;
}

.page-header {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-light);
}

.page-title {
  font-size: 2.5rem;
  font-weight: 900;
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}

.page-description {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Terms Page */
.terms-list {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
}

.term-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.625rem 1.25rem;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: 24px;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  transition: all var(--transition-base);
}

.term-badge:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--card-shadow-md);
}

/* Series Detail Page */
.series-detail {
  padding: 3rem 0;
}

.series-description {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.6;
}

.post-item {
  display: block;
  padding: 1.5rem;
  margin-bottom: 1rem;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  text-decoration: none;
  transition: all var(--transition-base);
}

.post-item:hover {
  transform: translateX(4px);
  box-shadow: var(--card-shadow-md);
  border-color: var(--accent);
}

.post-item-title {
  font-size: 1.125rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.post-item-title a {
  color: var(--text-primary);
  text-decoration: none;
}

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

.post-item-meta {
  font-size: 0.875rem;
  color: var(--text-tertiary);
  margin-bottom: 0.5rem;
  font-weight: 500;
}

.post-item-summary {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0;
}

/* 404 Page */
.error-page {
  text-align: center;
  padding: 6rem 0;
}

.error-code {
  font-size: 8rem;
  font-weight: 900;
  letter-spacing: -0.05em;
  background: var(--gradient-bar);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 1rem;
}

.error-message {
  font-size: 1.5rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.error-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  background: var(--accent);
  color: white;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  transition: all var(--transition-base);
}

.error-link:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--card-shadow-md);
}

/* Footer */
.site-footer {
  margin-top: 6rem;
  padding: 3rem 0;
  border-top: 1px solid var(--border-light);
  text-align: center;
}

.gradient-line {
  width: 120px;
  height: 3px;
  background: var(--gradient-bar);
  margin: 0 auto 2rem;
  border-radius: 2px;
}

.footer-content {
  color: var(--text-tertiary);
  font-size: 0.9375rem;
}

.footer-content p {
  margin-bottom: 0.5rem;
}

.footer-content a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-base);
}

.footer-content a:hover {
  color: var(--accent);
}

/* Search Overlay */
.search-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 200;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}

.search-overlay.active {
  display: flex;
  animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.search-modal {
  background: var(--card-bg);
  width: 100%;
  max-width: 600px;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-medium);
  animation: slideUp 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.search-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-light);
}

.search-icon {
  color: var(--text-tertiary);
  flex-shrink: 0;
}

.search-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-size: 1.125rem;
  color: var(--text-primary);
  font-family: inherit;
}

.search-input::placeholder {
  color: var(--text-tertiary);
}

.search-kbd {
  padding: 0.25rem 0.5rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-tertiary);
  font-family: 'JetBrains Mono', monospace;
}

.search-close {
  background: transparent;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 6px;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.search-results {
  max-height: 400px;
  overflow-y: auto;
}

.search-result-item {
  display: block;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-light);
  text-decoration: none;
  transition: background var(--transition-base);
}

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

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

.search-result-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.search-result-date {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
  margin-bottom: 0.5rem;
}

.search-result-snippet {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.search-result-snippet mark {
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
  padding: 0 2px;
}

.search-hint,
.search-no-results {
  padding: 2rem;
  text-align: center;
  color: var(--text-tertiary);
  font-size: 0.9375rem;
}

/* Selection */
::selection {
  background: var(--accent);
  color: white;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 12px;
  height: 12px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-medium);
  border-radius: 6px;
  border: 2px solid var(--bg-primary);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}

/* Responsive Design */
@media (max-width: 1024px) {
  .container {
    padding: 0 1.5rem;
  }

  .post-single {
    padding: 3rem 1.5rem;
  }
}

@media (max-width: 768px) {
  .nav-container {
    padding: 1rem 1.5rem;
  }

  .nav-menu {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .hero {
    padding: 4rem 0 3rem;
  }

  .series-section,
  .quick-start,
  .recent-posts {
    padding: 3rem 0;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .series-grid,
  .quick-start-grid {
    grid-template-columns: 1fr;
  }

  .post-card {
    padding: 1.5rem;
  }

  .post-single {
    padding: 2rem 1rem;
  }

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

  .post-navigation {
    grid-template-columns: 1fr;
  }

  pre {
    padding: 1rem;
    padding-top: 3rem;
    font-size: 0.8125rem;
  }

  .container {
    padding: 0 1rem;
  }

  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.375rem; }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  .search-modal {
    border-radius: 12px;
  }

  .search-kbd {
    display: none;
  }
}