/* ========================================
   CSS Custom Properties (Design Tokens)
   ======================================== */
:root {
  /* Primary Blue */
  --color-primary-50: #f0f5ff;
  --color-primary-100: #e0eaff;
  --color-primary-200: #c7d9fe;
  --color-primary-300: #a4bffc;
  --color-primary-400: #7c9cf8;
  --color-primary-500: #5b7cf2;
  --color-primary-600: #4361e6;
  --color-primary-700: #364dd3;
  --color-primary-800: #2f41ab;
  --color-primary-900: #2c3a87;
  --color-primary-950: #1e2659;

  /* Accent Green */
  --color-accent-500: #10b981;
  --color-accent-600: #059669;
  --color-accent-700: #047857;

  /* Gray Scale */
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-gray-900: #111827;
  --color-gray-950: #030712;

  /* Semantic */
  --bg-primary: #ffffff;
  --bg-secondary: var(--color-gray-50);
  --bg-header: rgba(255, 255, 255, 0.9);
  --text-primary: var(--color-gray-800);
  --text-secondary: var(--color-gray-600);
  --text-muted: var(--color-gray-500);
  --border-color: var(--color-gray-200);
  --border-color-alpha: rgba(229, 231, 235, 0.8);
  --link-color: var(--color-primary-600);
  --link-hover: var(--color-primary-700);
  --code-bg: var(--color-gray-100);
  --code-text: var(--color-primary-700);
  --selection-bg: var(--color-primary-200);
  --selection-text: var(--color-primary-900);
}

.dark {
  --bg-primary: var(--color-gray-950);
  --bg-secondary: var(--color-gray-900);
  --bg-header: rgba(3, 7, 18, 0.9);
  --text-primary: var(--color-gray-200);
  --text-secondary: var(--color-gray-400);
  --text-muted: var(--color-gray-500);
  --border-color: var(--color-gray-800);
  --border-color-alpha: rgba(31, 41, 55, 0.8);
  --link-color: var(--color-primary-400);
  --link-hover: var(--color-primary-300);
  --code-bg: var(--color-gray-800);
  --code-text: var(--color-primary-300);
  --selection-bg: var(--color-primary-800);
  --selection-text: var(--color-primary-100);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  font-feature-settings: "palt";
  line-height: 1.8;
  letter-spacing: 0.02em;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.2s, color 0.2s;
}

::selection {
  background-color: var(--selection-bg);
  color: var(--selection-text);
}

a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover {
  color: var(--link-hover);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ========================================
   Layout
   ======================================== */
.site-container {
  flex: 1;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1rem;
}

@media (min-width: 640px) {
  .container { padding: 0 1.5rem; }
}
@media (min-width: 1024px) {
  .container { padding: 0 2rem; }
}

.content-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  padding: 2rem 0;
}

@media (min-width: 1024px) {
  .content-layout {
    grid-template-columns: 1fr 320px;
    padding: 3rem 0;
  }
}

/* ========================================
   Header
   ======================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid var(--border-color-alpha);
  background-color: var(--bg-header);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-primary);
}

.site-logo-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  background-color: var(--color-primary-600);
  color: #fff;
  border-radius: 0.5rem;
  font-weight: 700;
  font-size: 0.875rem;
}

.site-logo-text {
  font-size: 1rem;
  font-weight: 700;
}

.site-logo-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-left: 0.25rem;
}

/* Desktop Nav */
.nav-desktop {
  display: none;
  align-items: center;
  gap: 0.25rem;
}

@media (min-width: 768px) {
  .nav-desktop { display: flex; }
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: background-color 0.2s, color 0.2s;
}

.nav-link:hover {
  background-color: var(--color-gray-100);
  color: var(--text-primary);
}
.dark .nav-link:hover {
  background-color: var(--color-gray-800);
}

.nav-link.active {
  background-color: var(--color-primary-50);
  color: var(--color-primary-600);
}
.dark .nav-link.active {
  background-color: rgba(67, 97, 230, 0.1);
  color: var(--color-primary-400);
}

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

/* Theme Toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 0.5rem;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: background-color 0.2s, color 0.2s;
}
.theme-toggle:hover {
  background-color: var(--color-gray-100);
  color: var(--text-primary);
}
.dark .theme-toggle:hover {
  background-color: var(--color-gray-800);
}
.theme-toggle svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* Mobile Menu Button */
.mobile-menu-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 0.5rem;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: background-color 0.2s;
}
.mobile-menu-btn:hover {
  background-color: var(--color-gray-100);
}
.dark .mobile-menu-btn:hover {
  background-color: var(--color-gray-800);
}
.mobile-menu-btn svg {
  width: 1.5rem;
  height: 1.5rem;
}

@media (min-width: 768px) {
  .mobile-menu-btn { display: none; }
}

/* Mobile Navigation */
.nav-mobile {
  display: none;
  border-top: 1px solid var(--border-color);
  padding: 0.75rem 0;
}
.nav-mobile.is-open {
  display: block;
}

@media (min-width: 768px) {
  .nav-mobile { display: none !important; }
}

.nav-mobile .nav-link {
  display: block;
  padding: 0.625rem 1rem;
  border-radius: 0.5rem;
}

/* ========================================
   Footer
   ======================================== */
.site-footer {
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  padding: 3rem 0 2rem;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.footer-section h3 {
  font-size: 0.875rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-links a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ========================================
   Cards
   ======================================== */
.card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  overflow: hidden;
  transition: box-shadow 0.2s, transform 0.15s;
}
.card:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}
.dark .card:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.card-thumbnail {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-gray-100);
  border-bottom: 1px solid var(--border-color);
}
.dark .card-thumbnail {
  background-color: var(--color-gray-800);
}
.card-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}
.card:hover .card-thumbnail img {
  transform: scale(1.03);
}
/* サムネイルがない場合のプレースホルダ */
.card-thumbnail:empty {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-gray-300);
}

.card-body {
  padding: 1.25rem;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  flex-wrap: wrap;
}

.card-updated {
  font-size: 0.6875rem;
  color: var(--color-accent-600);
}
.dark .card-updated {
  color: var(--color-accent-500);
}

.card-category {
  display: inline-block;
  padding: 0.125rem 0.5rem;
  border-radius: 9999px;
  font-size: 0.6875rem;
  font-weight: 700;
  background-color: var(--color-primary-50);
  color: var(--color-primary-600);
  text-decoration: none;
  transition: background-color 0.2s;
}
.dark .card-category {
  background-color: rgba(67, 97, 230, 0.1);
  color: var(--color-primary-400);
}
.card-category:hover {
  background-color: var(--color-primary-100);
  color: var(--color-primary-700);
}
.dark .card-category:hover {
  background-color: rgba(67, 97, 230, 0.2);
}

.card-title {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.5;
  margin-bottom: 0.5rem;
}
.card-title a {
  color: var(--text-primary);
  text-decoration: none;
}
.card-title a:hover {
  color: var(--color-primary-600);
}
.dark .card-title a:hover {
  color: var(--color-primary-400);
}

.card-excerpt {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* Featured card (large) */
.card-featured {
  grid-column: 1 / -1;
  margin-bottom: 1.5rem;
}
.card-featured .card-thumbnail {
  aspect-ratio: 2 / 1;
}
.card-featured .card-body {
  padding: 1.5rem;
}
.card-featured .card-title {
  font-size: 1.125rem;
}

@media (min-width: 768px) {
  .card-featured {
    display: grid;
    grid-template-columns: 3fr 2fr;
  }
  .card-featured .card-thumbnail {
    aspect-ratio: auto;
    min-height: 280px;
    border-bottom: none;
    border-right: 1px solid var(--border-color);
  }
  .card-featured .card-body {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 2rem;
  }
  .card-featured .card-title {
    font-size: 1.375rem;
  }
  .card-featured .card-excerpt {
    -webkit-line-clamp: 4;
  }
}

/* Post grid */
.post-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .post-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .post-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ========================================
   Category Navigation
   ======================================== */
.category-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 1.5rem 0;
}

.category-nav a {
  display: inline-flex;
  align-items: center;
  padding: 0.375rem 1rem;
  border-radius: 9999px;
  font-size: 0.8125rem;
  font-weight: 500;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}
.category-nav a:hover,
.category-nav a.active {
  background-color: var(--color-primary-600);
  border-color: var(--color-primary-600);
  color: #fff;
}
.dark .category-nav a:hover,
.dark .category-nav a.active {
  background-color: var(--color-primary-700);
  border-color: var(--color-primary-700);
}

/* ========================================
   Sidebar
   ======================================== */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.sidebar-widget {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  padding: 1.5rem;
}

.sidebar-widget h3 {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--color-primary-600);
  color: var(--text-primary);
}

.sidebar-widget .widget-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.sidebar-widget .widget-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 0.75rem;
  border-radius: 0.375rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.15s;
}
.sidebar-widget .widget-list a:hover {
  background-color: var(--color-gray-50);
  color: var(--text-primary);
}
.dark .sidebar-widget .widget-list a:hover {
  background-color: var(--color-gray-800);
}

.widget-count {
  font-size: 0.75rem;
  color: var(--text-muted);
  background-color: var(--color-gray-100);
  padding: 0.125rem 0.5rem;
  border-radius: 9999px;
}
.dark .widget-count {
  background-color: var(--color-gray-800);
}

/* Popular posts widget */
.popular-post-item {
  display: flex;
  gap: 0.75rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border-color);
}
.popular-post-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}
.popular-post-item:first-child {
  padding-top: 0;
}

.popular-post-thumb {
  width: 5rem;
  min-width: 5rem;
  aspect-ratio: 1;
  border-radius: 0.5rem;
  overflow: hidden;
  background-color: var(--color-gray-100);
}
.dark .popular-post-thumb {
  background-color: var(--color-gray-800);
}
.popular-post-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.popular-post-info {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.25rem;
}
.popular-post-info .post-title {
  font-size: 0.8125rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--text-primary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.popular-post-info .post-title:hover {
  color: var(--color-primary-600);
}
.dark .popular-post-info .post-title:hover {
  color: var(--color-primary-400);
}
.popular-post-info .post-date {
  font-size: 0.6875rem;
  color: var(--text-muted);
}

/* CTA Banner */
.cta-banner {
  display: block;
  background: linear-gradient(135deg, var(--color-primary-600), var(--color-primary-800));
  color: #fff;
  padding: 1.5rem;
  border-radius: 0.75rem;
  text-decoration: none;
  transition: opacity 0.2s, transform 0.15s;
}
.cta-banner:hover {
  opacity: 0.95;
  transform: translateY(-1px);
  color: #fff;
}
.cta-banner-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.cta-banner-desc {
  font-size: 0.8125rem;
  opacity: 0.9;
  line-height: 1.6;
  margin-bottom: 1rem;
}
.cta-banner-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 1.25rem;
  background-color: #fff;
  color: var(--color-primary-700);
  font-size: 0.8125rem;
  font-weight: 700;
  border-radius: 0.375rem;
  transition: background-color 0.2s;
}
.cta-banner:hover .cta-banner-btn {
  background-color: var(--color-primary-50);
}

/* ========================================
   Single Post
   ======================================== */
.post-header {
  padding: 2rem 0;
}

.post-breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}
.post-breadcrumb a {
  color: var(--text-muted);
  text-decoration: none;
}
.post-breadcrumb a:hover {
  color: var(--link-color);
}
.post-breadcrumb .separator {
  color: var(--color-gray-300);
}
.dark .post-breadcrumb .separator {
  color: var(--color-gray-700);
}

.post-header .card-category {
  margin-bottom: 0.75rem;
}

.post-title {
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

@media (min-width: 640px) {
  .post-title { font-size: 2rem; }
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.post-meta-item {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.post-meta-item svg {
  width: 1rem;
  height: 1rem;
}

.post-featured-image {
  margin: 1.5rem 0;
  border-radius: 0.75rem;
  overflow: hidden;
}
.post-featured-image img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* Table of Contents */
.toc {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  padding: 1.5rem;
  margin: 2rem 0;
}

.toc-title {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  color: var(--text-primary);
  background: none;
  border: none;
  padding: 0;
  font-family: inherit;
  width: 100%;
  text-align: left;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}
.toc-list a {
  display: block;
  padding: 0.375rem 0.75rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: 0.375rem;
  transition: all 0.15s;
  border-left: 2px solid transparent;
}
.toc-list a:hover {
  background-color: var(--color-primary-50);
  color: var(--color-primary-600);
  border-left-color: var(--color-primary-600);
}
.dark .toc-list a:hover {
  background-color: rgba(67, 97, 230, 0.1);
  color: var(--color-primary-400);
  border-left-color: var(--color-primary-400);
}
.toc-list .toc-h3 {
  padding-left: 1.5rem;
  font-size: 0.8125rem;
}

/* Post Content */
.post-content {
  padding-bottom: 2rem;
}

.post-content h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin: 2.5rem 0 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
  line-height: 1.4;
}

.post-content h3 {
  font-size: 1.125rem;
  font-weight: 700;
  margin: 2rem 0 1rem;
  color: var(--text-primary);
  line-height: 1.5;
}

.post-content h4 {
  font-size: 1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
  color: var(--text-primary);
}

.post-content p {
  margin: 1.25rem 0;
  line-height: 1.85;
  color: var(--text-secondary);
}

.post-content ul,
.post-content ol {
  margin: 1.25rem 0;
  padding-left: 1.5rem;
}

.post-content ul { list-style: disc; }
.post-content ol { list-style: decimal; }

.post-content li {
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.post-content blockquote {
  margin: 1.5rem 0;
  padding: 0.25rem 1.25rem;
  border-left: 4px solid var(--color-primary-300);
  background-color: var(--color-primary-50);
  border-radius: 0 0.5rem 0.5rem 0;
  color: var(--text-secondary);
  font-style: italic;
}
.dark .post-content blockquote {
  border-left-color: var(--color-primary-600);
  background-color: rgba(30, 38, 89, 0.2);
}

.post-content a {
  color: var(--link-color);
  text-decoration: underline;
  text-decoration-color: var(--color-primary-300);
  text-underline-offset: 2px;
  font-weight: 500;
  transition: color 0.2s, text-decoration-color 0.2s;
}
.dark .post-content a {
  text-decoration-color: var(--color-primary-700);
}
.post-content a:hover {
  text-decoration-color: var(--color-primary-500);
}

.post-content strong {
  font-weight: 700;
  color: var(--text-primary);
}

.post-content img {
  margin: 1.5rem 0;
  border-radius: 0.75rem;
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}

.post-content table {
  width: 100%;
  margin: 1.5rem 0;
  font-size: 0.875rem;
  border-collapse: collapse;
}
.post-content thead {
  background-color: var(--bg-secondary);
}
.post-content th,
.post-content td {
  border: 1px solid var(--border-color);
  padding: 0.75rem 1rem;
  text-align: left;
}
.post-content th {
  font-weight: 600;
  color: var(--text-primary);
}
.post-content td {
  color: var(--text-secondary);
}

.post-content hr {
  margin: 2.5rem 0;
  border: none;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--color-gray-300), transparent);
}
.dark .post-content hr {
  background: linear-gradient(to right, transparent, var(--color-gray-700), transparent);
}

/* Inline code */
.post-content :not(pre) > code {
  background-color: var(--code-bg);
  color: var(--code-text);
  padding: 0.125rem 0.375rem;
  border-radius: 0.375rem;
  font-size: 0.9em;
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Consolas, "Liberation Mono", "Courier New", monospace;
  border: 1px solid var(--border-color);
}

/* Code blocks */
.post-content pre {
  margin: 1.5rem 0;
  padding: 1.25rem;
  background-color: #1e1e2e;
  border: 1px solid var(--color-gray-800);
  border-radius: 0.75rem;
  overflow-x: auto;
  font-size: 0.875rem;
  line-height: 1.6;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}
.dark .post-content pre {
  background-color: #181825;
}

.post-content pre code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.875rem;
  background: none;
  border: none;
  padding: 0;
  color: #cdd6f4;
}

/* WordPress specific blocks */
.wp-block-code {
  margin: 1.5rem 0;
}

.wp-block-image {
  margin: 1.5rem 0;
}
.wp-block-image img {
  border-radius: 0.75rem;
}

.wp-block-quote {
  margin: 1.5rem 0;
  padding: 0.25rem 1.25rem;
  border-left: 4px solid var(--color-primary-300);
  background-color: var(--color-primary-50);
  border-radius: 0 0.5rem 0.5rem 0;
}
.dark .wp-block-quote {
  border-left-color: var(--color-primary-600);
  background-color: rgba(30, 38, 89, 0.2);
}

.wp-block-table {
  overflow-x: auto;
}

/* ========================================
   Chapter CTA
   ======================================== */
.chapter-cta {
  display: block;
  margin: 2rem 0;
  padding: 1.5rem;
  background: linear-gradient(135deg, var(--color-primary-50), var(--color-primary-100));
  border: 1px solid var(--color-primary-200);
  border-radius: 0.75rem;
  text-decoration: none;
  transition: transform 0.15s, box-shadow 0.2s;
}
.dark .chapter-cta {
  background: linear-gradient(135deg, rgba(30, 38, 89, 0.3), rgba(47, 65, 171, 0.2));
  border-color: var(--color-primary-800);
}
.chapter-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(67, 97, 230, 0.15);
}
.chapter-cta-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-primary-600);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.25rem;
}
.dark .chapter-cta-label {
  color: var(--color-primary-400);
}
.chapter-cta-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* ========================================
   Post Navigation
   ======================================== */
.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  padding: 2rem 0;
  border-top: 1px solid var(--border-color);
}

.post-nav-item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  text-decoration: none;
  transition: border-color 0.2s, background-color 0.2s;
}
.post-nav-item:hover {
  border-color: var(--color-primary-300);
  background-color: var(--color-primary-50);
}
.dark .post-nav-item:hover {
  border-color: var(--color-primary-700);
  background-color: rgba(67, 97, 230, 0.05);
}

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

.post-nav-label {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.post-nav-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-primary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ========================================
   Share Buttons
   ======================================== */
.share-buttons {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1.5rem 0;
}

.share-buttons span {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
}

.share-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 9999px;
  border: none;
  cursor: pointer;
  color: #fff;
  text-decoration: none;
  transition: opacity 0.2s, transform 0.15s;
}
.share-btn:hover {
  opacity: 0.85;
  transform: scale(1.05);
  color: #fff;
}
.share-btn svg {
  width: 1.125rem;
  height: 1.125rem;
}
.share-btn.twitter { background-color: #000; }
.share-btn.facebook { background-color: #1877f2; }
.share-btn.hatena { background-color: #00a4de; }
.share-btn.line { background-color: #06c755; }
.share-btn.copy-link {
  background-color: var(--color-gray-400);
}

/* ========================================
   Related Posts
   ======================================== */
.related-posts {
  padding: 2rem 0;
  border-top: 1px solid var(--border-color);
}
.related-posts h2 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

/* ========================================
   Pagination
   ======================================== */
.pagination {
  padding: 2rem 0;
}

.pagination .nav-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  flex-wrap: wrap;
}

.pagination .nav-links a,
.pagination .nav-links span,
.pagination a,
.pagination span {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 2.5rem;
  height: 2.5rem;
  padding: 0 0.5rem;
  border-radius: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.15s;
}

.pagination a,
.pagination .nav-links a.page-numbers {
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}
.pagination a:hover,
.pagination .nav-links a.page-numbers:hover {
  background-color: var(--color-primary-50);
  border-color: var(--color-primary-300);
  color: var(--color-primary-600);
}
.dark .pagination a:hover,
.dark .pagination .nav-links a.page-numbers:hover {
  background-color: rgba(67, 97, 230, 0.1);
  border-color: var(--color-primary-700);
  color: var(--color-primary-400);
}

.pagination .current,
.pagination .nav-links span.page-numbers.current {
  background-color: var(--color-primary-600);
  color: #fff;
  border: 1px solid var(--color-primary-600);
}

/* ========================================
   Page Header (Archive / Category)
   ======================================== */
.page-header {
  padding: 2rem 0 1rem;
}
.page-header h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}
.page-header .description {
  font-size: 0.9375rem;
  color: var(--text-secondary);
}

/* ========================================
   Search
   ======================================== */
.search-form {
  display: flex;
  gap: 0.5rem;
}
.search-form input[type="search"] {
  flex: 1;
  padding: 0.625rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 0.875rem;
  outline: none;
  transition: border-color 0.2s;
}
.search-form input[type="search"]:focus {
  border-color: var(--color-primary-400);
  box-shadow: 0 0 0 3px rgba(67, 97, 230, 0.1);
}
.search-form button {
  padding: 0.625rem 1.25rem;
  background-color: var(--color-primary-600);
  color: #fff;
  border: none;
  border-radius: 0.5rem;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
}
.search-form button:hover {
  background-color: var(--color-primary-700);
}

/* ========================================
   404 Page
   ======================================== */
.error-404 {
  text-align: center;
  padding: 6rem 1rem;
}
.error-404 h1 {
  font-size: 5rem;
  font-weight: 700;
  color: var(--color-primary-600);
  margin-bottom: 1rem;
}
.error-404 p {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}
.error-404 a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  background-color: var(--color-primary-600);
  color: #fff;
  border-radius: 0.5rem;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.2s;
}
.error-404 a:hover {
  background-color: var(--color-primary-700);
  color: #fff;
}

/* ========================================
   Comments
   ======================================== */
.comments-area {
  padding: 2rem 0;
  border-top: 1px solid var(--border-color);
}
.comments-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}
.comment-list {
  list-style: none;
}
.comment {
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border-color);
}
.comment-author {
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--text-primary);
}
.comment-date {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-left: 0.5rem;
}
.comment-body p {
  margin: 0.5rem 0;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.comment-respond .comment-form label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--text-primary);
}
.comment-respond .comment-form input,
.comment-respond .comment-form textarea {
  width: 100%;
  padding: 0.625rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 0.875rem;
  margin-bottom: 1rem;
  font-family: inherit;
}
.comment-respond .comment-form input:focus,
.comment-respond .comment-form textarea:focus {
  outline: none;
  border-color: var(--color-primary-400);
  box-shadow: 0 0 0 3px rgba(67, 97, 230, 0.1);
}
.comment-respond .comment-form .submit {
  width: auto;
  padding: 0.625rem 1.5rem;
  background-color: var(--color-primary-600);
  color: #fff;
  border: none;
  border-radius: 0.5rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
}
.comment-respond .comment-form .submit:hover {
  background-color: var(--color-primary-700);
}

/* ========================================
   Utility
   ======================================== */
.screen-reader-text {
  clip: rect(1px, 1px, 1px, 1px);
  height: 1px;
  overflow: hidden;
  position: absolute;
  width: 1px;
  word-wrap: normal;
}

/* スキップナビゲーション: フォーカス時に表示 */
a.skip-link.screen-reader-text:focus {
  clip: auto;
  height: auto;
  width: auto;
  overflow: visible;
  position: fixed;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 100;
  padding: 0.75rem 1.5rem;
  background-color: var(--color-primary-600);
  color: #fff;
  font-size: 0.875rem;
  font-weight: 700;
  border-radius: 0.5rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  text-decoration: none;
}

/* グローバル フォーカスリング */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--color-primary-500);
  outline-offset: 2px;
}

.text-center { text-align: center; }
.mt-0 { margin-top: 0; }

/* ========================================
   Gutenberg alignment support
   ======================================== */
.alignwide {
  margin-left: -1rem;
  margin-right: -1rem;
  max-width: calc(100% + 2rem);
}
.alignfull {
  margin-left: calc(-50vw + 50%);
  margin-right: calc(-50vw + 50%);
  max-width: 100vw;
  width: 100vw;
}
.aligncenter {
  display: block;
  margin-left: auto;
  margin-right: auto;
}
.alignleft {
  float: left;
  margin-right: 1.5rem;
  margin-bottom: 1rem;
}
.alignright {
  float: right;
  margin-left: 1.5rem;
  margin-bottom: 1rem;
}

/* ========================================
   Author Box（監修者情報）
   ======================================== */
.author-box {
  margin: 2.5rem 0;
  padding: 1.5rem;
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  background-color: var(--bg-secondary);
}
.author-box-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.75rem;
}
.author-box-avatar {
  width: 3.5rem;
  height: 3.5rem;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--border-color);
}
.author-box-label {
  display: block;
  font-size: 0.6875rem;
  font-weight: 700;
  color: var(--color-primary-600);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.dark .author-box-label {
  color: var(--color-primary-400);
}
.author-box-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
}
.author-box-desc {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin: 0 0 0.75rem;
}
.author-box-link {
  display: inline-block;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-primary-600);
  text-decoration: none;
}
.dark .author-box-link {
  color: var(--color-primary-400);
}
.author-box-link:hover {
  text-decoration: underline;
}

/* Sidebar author */
.sidebar-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}
.sidebar-author-avatar {
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--border-color);
}
.sidebar-author-name {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--text-primary);
}
.sidebar-author-desc {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin: 0;
}

/* ========================================
   Post Intro（導入文 - post-contentと同じスタイル）
   ======================================== */
.post-intro p {
  margin: 1.25rem 0;
  line-height: 1.85;
  color: var(--text-secondary);
}
.post-intro a {
  color: var(--link-color);
  text-decoration: underline;
  text-underline-offset: 2px;
  font-weight: 500;
}
.post-intro strong {
  font-weight: 700;
  color: var(--text-primary);
}

/* ========================================
   Responsive adjustments
   ======================================== */
@media (max-width: 767px) {
  .post-title {
    font-size: 1.375rem;
  }
  .post-nav {
    grid-template-columns: 1fr;
  }
  .share-buttons {
    flex-wrap: wrap;
  }
}