:root {
  --color-primary: #1a1a2e;
  --color-primary-light: #16213e;
  --color-secondary: #0f3460;
  --color-accent: #e94560;
  --color-accent-warm: #f59e0b;
  --color-bg: #fafbfc;
  --color-bg-white: #ffffff;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-text-lighter: #9ca3af;
  --color-border: #e5e7eb;
  --color-border-light: #f3f4f6;
  --color-link: #3b82f6;
  --color-link-hover: #2563eb;
  --font-sans: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
  --shadow-sm: 0 1px 2px 0 rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --max-width: 1200px;
  --header-height: 70px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--color-link); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--color-link-hover); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }

/* ========== HEADER ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(26, 26, 46, 0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  height: var(--header-height);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  font-size: 18px;
}

.logo-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-warm));
  border-radius: var(--radius-sm);
  font-size: 20px;
  font-weight: 900;
  color: #fff;
}

.logo-text { letter-spacing: 0.02em; }

.global-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  color: rgba(255,255,255,0.75);
  font-size: 13px;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: #fff;
  background: rgba(255,255,255,0.1);
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.mobile-menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: all 0.3s;
}

.mobile-menu-btn.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-menu-btn.active span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

@media (max-width: 900px) {
  .mobile-menu-btn { display: flex; }
  .global-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(26, 26, 46, 0.98);
    flex-direction: column;
    padding: 24px;
    gap: 8px;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    overflow-y: auto;
  }
  .global-nav.open { transform: translateX(0); }
  .nav-link {
    font-size: 16px;
    padding: 14px 20px;
    width: 100%;
    border-radius: var(--radius-md);
  }
}

/* ========== HERO ========== */
.hero {
  position: relative;
  min-height: 480px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-gradient {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 30%, #0f3460 60%, #1a1a2e 100%);
}

.hero-pattern {
  position: absolute;
  inset: 0;
  opacity: 0.03;
  background-image:
    radial-gradient(circle at 20% 50%, #fff 1px, transparent 1px),
    radial-gradient(circle at 80% 20%, #fff 1px, transparent 1px),
    radial-gradient(circle at 60% 80%, #fff 1px, transparent 1px);
  background-size: 60px 60px, 80px 80px, 100px 100px;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 120px;
  background: linear-gradient(to top, var(--color-bg), transparent);
  z-index: 1;
}

.hero-inner {
  position: relative;
  z-index: 2;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 80px 24px 60px;
  width: 100%;
}

.hero-slides { position: relative; min-height: 280px; }

.hero-slide {
  display: none;
  animation: fadeSlide 0.6s ease;
}

.hero-slide.active { display: block; }

@keyframes fadeSlide {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-category {
  display: inline-block;
  background: var(--color-accent);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}

.hero-title {
  font-size: 32px;
  font-weight: 900;
  color: #fff;
  line-height: 1.4;
  margin-bottom: 16px;
  max-width: 700px;
}

.hero-title a { color: #fff; }
.hero-title a:hover { color: var(--color-accent-warm); }

.hero-meta {
  color: rgba(255,255,255,0.6);
  font-size: 14px;
  margin-bottom: 24px;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-accent-warm);
  color: var(--color-primary);
  font-weight: 700;
  font-size: 14px;
  padding: 12px 28px;
  border-radius: 30px;
  transition: all 0.3s;
}

.hero-cta:hover {
  background: #fff;
  color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(245, 158, 11, 0.3);
}

.hero-dots {
  display: flex;
  gap: 8px;
  margin-top: 32px;
}

.hero-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid rgba(255,255,255,0.3);
  background: transparent;
  cursor: pointer;
  transition: all 0.3s;
  padding: 0;
}

.hero-dot.active {
  background: var(--color-accent-warm);
  border-color: var(--color-accent-warm);
  width: 28px;
  border-radius: 10px;
}

@media (max-width: 768px) {
  .hero { min-height: 400px; }
  .hero-inner { padding: 60px 20px 50px; }
  .hero-title { font-size: 22px; }
  .hero-slides { min-height: 220px; }
}

/* ========== SECTIONS ========== */
.section {
  padding: 64px 0;
}

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-title {
  font-size: 28px;
  font-weight: 900;
  color: var(--color-primary);
  margin-bottom: 8px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-warm));
  border-radius: 3px;
}

.section-subtitle {
  color: var(--color-text-light);
  font-size: 15px;
  margin-top: 16px;
}

/* ========== CATEGORY GRID ========== */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 16px;
}

.category-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 24px 16px;
  background: var(--color-bg-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-light);
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.3s;
}

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

.category-card-icon {
  width: 40px;
  height: 40px;
  color: var(--color-secondary);
}

.category-card-icon svg { width: 100%; height: 100%; }

.category-card h3 {
  font-size: 14px;
  font-weight: 700;
  text-align: center;
}

.category-card-count {
  font-size: 12px;
  color: var(--color-text-lighter);
}

/* ========== ARTICLE GRID ========== */
.article-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.article-grid.mini-grid {
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
}

.article-card {
  background: var(--color-bg-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border-light);
  transition: all 0.3s;
}

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

.article-card-link {
  display: block;
  color: var(--color-text);
  text-decoration: none;
}

.article-card-link:hover { color: var(--color-text); }

.article-card-image {
  height: 180px;
  overflow: hidden;
  position: relative;
}

.article-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s;
}

.article-card:hover .article-card-image img { transform: scale(1.05); }

.article-card-image.placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #e8eaf6, #f5f5f5);
}

.article-card-image.placeholder svg { width: 60px; height: 60px; opacity: 0.5; }

.article-card-body { padding: 20px; }

.article-card-category {
  display: inline-block;
  font-size: 11px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 8px;
  letter-spacing: 0.03em;
}

.article-card-title {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.5;
  margin-bottom: 10px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-date {
  font-size: 12px;
  color: var(--color-text-lighter);
}

.article-card.mini .article-card-title {
  font-size: 14px;
  -webkit-line-clamp: 2;
}

/* ========== BREADCRUMB ========== */
.breadcrumb {
  background: var(--color-bg-white);
  border-bottom: 1px solid var(--color-border-light);
}

.breadcrumb ol {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.breadcrumb li {
  font-size: 13px;
  color: var(--color-text-light);
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb li + li::before {
  content: '›';
  color: var(--color-text-lighter);
  font-size: 14px;
}

.breadcrumb a { color: var(--color-text-light); }
.breadcrumb a:hover { color: var(--color-link); }
.breadcrumb [aria-current="page"] { color: var(--color-text); font-weight: 500; }

/* ========== ARTICLE PAGE ========== */
.article-page {
  padding: 40px 0 64px;
}

.article-page-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 40px;
}

.article-main { flex: 1; min-width: 0; }

.article-header { margin-bottom: 36px; }

.article-category-tag {
  display: inline-block;
  margin-bottom: 12px;
}

.article-category-tag a {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--color-accent);
  background: rgba(233, 69, 96, 0.08);
  padding: 4px 14px;
  border-radius: 20px;
  transition: all 0.2s;
}

.article-category-tag a:hover {
  background: var(--color-accent);
  color: #fff;
}

.article-title {
  font-size: 30px;
  font-weight: 900;
  line-height: 1.45;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.article-meta {
  display: flex;
  gap: 20px;
  font-size: 13px;
  color: var(--color-text-light);
}

.article-eyecatch {
  margin-top: 24px;
  border-radius: var(--radius-md);
  overflow: hidden;
}

.article-eyecatch img {
  width: 100%;
  border-radius: var(--radius-md);
}

/* TOC Sidebar */
.toc-sidebar {
  width: 260px;
  flex-shrink: 0;
  order: 2;
}

.toc-inner {
  position: sticky;
  top: calc(var(--header-height) + 24px);
  background: var(--color-bg-white);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: 20px;
  max-height: calc(100vh - var(--header-height) - 48px);
  overflow-y: auto;
}

.toc-title {
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--color-primary);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-accent);
}

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

.toc a {
  display: block;
  font-size: 13px;
  color: var(--color-text-light);
  padding: 4px 0;
  line-height: 1.5;
  transition: color 0.2s;
}

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

.toc ul ul { padding-left: 14px; }
.toc ul ul a { font-size: 12px; }

/* Article body prose */
.prose { line-height: 1.9; }

.prose h1 {
  font-size: 26px;
  font-weight: 900;
  color: var(--color-primary);
  margin: 48px 0 20px;
  padding-bottom: 12px;
  border-bottom: 3px solid var(--color-accent);
}

.prose h2 {
  font-size: 22px;
  font-weight: 800;
  color: var(--color-primary);
  margin: 40px 0 16px;
  padding-left: 16px;
  border-left: 4px solid var(--color-accent);
}

.prose h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-secondary);
  margin: 32px 0 12px;
}

.prose h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-text);
  margin: 24px 0 8px;
}

.prose p { margin-bottom: 16px; }

.prose a {
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.prose ul, .prose ol {
  margin: 16px 0;
  padding-left: 24px;
}

.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: 6px; }

.prose blockquote {
  margin: 24px 0;
  padding: 16px 20px;
  background: #fefce8;
  border-left: 4px solid var(--color-accent-warm);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--color-text);
}

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

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 14px;
}

.prose th, .prose td {
  padding: 12px 16px;
  border: 1px solid var(--color-border);
  text-align: left;
}

.prose th {
  background: var(--color-primary);
  color: #fff;
  font-weight: 700;
}

.prose tr:nth-child(even) { background: var(--color-border-light); }

.prose hr {
  border: none;
  height: 2px;
  background: var(--color-border);
  margin: 40px 0;
}

.prose strong { font-weight: 700; color: var(--color-primary); }

.prose img {
  border-radius: var(--radius-md);
  margin: 20px 0;
}

.prose code {
  background: #f1f5f9;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
}

.prose .headerlink {
  font-size: 0.6em;
  opacity: 0;
  margin-left: 6px;
  transition: opacity 0.2s;
  text-decoration: none;
}

.prose h1:hover .headerlink,
.prose h2:hover .headerlink,
.prose h3:hover .headerlink,
.prose h4:hover .headerlink { opacity: 0.5; }

@media (max-width: 900px) {
  .article-page-inner {
    flex-direction: column;
  }
  .toc-sidebar {
    width: 100%;
    order: 0;
    margin-bottom: 24px;
  }
  .toc-inner {
    position: static;
    max-height: 300px;
  }
  .article-title { font-size: 22px; }
}

/* ========== RELATED SECTION ========== */
.related-section {
  background: var(--color-border-light);
}

/* ========== CATEGORY PAGE ========== */
.category-page {
  padding: 40px 0 64px;
}

.category-page-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 40px;
}

.category-main { flex: 1; min-width: 0; }

.category-header {
  margin-bottom: 32px;
  padding-bottom: 20px;
  border-bottom: 2px solid var(--color-border);
}

.category-header h1 {
  font-size: 28px;
  font-weight: 900;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.category-desc {
  color: var(--color-text-light);
  font-size: 14px;
}

.category-sidebar {
  width: 260px;
  flex-shrink: 0;
}

.sidebar-widget {
  position: sticky;
  top: calc(var(--header-height) + 24px);
  background: var(--color-bg-white);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sidebar-title {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-accent);
  color: var(--color-primary);
}

.sidebar-cat-list li + li { border-top: 1px solid var(--color-border-light); }

.sidebar-cat-link {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
  font-size: 13px;
  color: var(--color-text);
  transition: color 0.2s;
}

.sidebar-cat-link:hover { color: var(--color-accent); }

.sidebar-cat-count {
  font-size: 11px;
  color: var(--color-text-lighter);
}

@media (max-width: 900px) {
  .category-page-inner { flex-direction: column; }
  .category-sidebar { width: 100%; }
  .sidebar-widget { position: static; }
}

/* ========== CATEGORY INDEX ========== */
.category-index-section { background: var(--color-bg); }

.category-index-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}

.category-index-card {
  display: block;
  background: var(--color-bg-white);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  color: var(--color-text);
  text-decoration: none;
  transition: all 0.3s;
}

.category-index-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-accent);
  color: var(--color-text);
}

.category-index-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.category-index-count {
  font-size: 12px;
  color: var(--color-text-lighter);
  display: block;
  margin-bottom: 12px;
}

.category-index-articles {
  margin-bottom: 12px;
}

.category-index-articles li {
  font-size: 13px;
  color: var(--color-text-light);
  padding: 4px 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.category-index-link {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-accent);
}

/* ========== CTA ========== */
.cta-section { background: var(--color-primary); }

.cta-box {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.cta-box h2 {
  font-size: 28px;
  font-weight: 900;
  color: #fff;
  margin-bottom: 12px;
}

.cta-box p {
  color: rgba(255,255,255,0.7);
  font-size: 15px;
  margin-bottom: 28px;
}

.cta-buttons {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 30px;
  font-size: 15px;
  font-weight: 700;
  transition: all 0.3s;
  border: none;
  cursor: pointer;
  text-decoration: none;
}

.btn-primary {
  background: var(--color-accent-warm);
  color: var(--color-primary);
}

.btn-primary:hover {
  background: #fff;
  color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(255,255,255,0.2);
  text-decoration: none;
}

.btn-secondary {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,0.3);
}

.btn-secondary:hover {
  border-color: #fff;
  text-decoration: none;
}

/* ========== FOOTER ========== */
.site-footer {
  background: var(--color-primary);
  color: rgba(255,255,255,0.6);
  padding: 48px 0 0;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-brand .logo { margin-bottom: 12px; }
.footer-desc { font-size: 14px; line-height: 1.7; }

.footer-links h4 {
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 16px;
}

.footer-links ul li + li { margin-top: 8px; }

.footer-links a {
  color: rgba(255,255,255,0.6);
  font-size: 13px;
  transition: color 0.2s;
}

.footer-links a:hover { color: var(--color-accent-warm); text-decoration: none; }

.footer-bottom {
  padding: 20px 0;
  text-align: center;
  font-size: 12px;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

/* ========== UTILITIES ========== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========== SCROLLBAR ========== */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--color-bg); }
::-webkit-scrollbar-thumb {
  background: var(--color-text-lighter);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover { background: var(--color-text-light); }