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

:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-bg: #ffffff;
  --color-bg-gray: #f9fafb;
  --color-border: #e5e7eb;
  --max-width: 1100px;
  --content-width: 740px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.8;
}

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

a:hover {
  text-decoration: underline;
}

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

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

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

.site-logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
}

.site-logo:hover {
  text-decoration: none;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
}

.site-nav a {
  color: var(--color-text-light);
  font-size: 0.9rem;
}

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

/* Hero */
.hero {
  text-align: center;
  padding: 4rem 0 3rem;
}

.hero h1 {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

.hero p {
  color: var(--color-text-light);
  font-size: 1.1rem;
}

/* Article List */
.latest-articles,
.categories-section {
  padding: 2rem 0;
}

.latest-articles h2,
.categories-section h2 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
}

.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.article-card {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  overflow: hidden;
  transition: box-shadow 0.2s;
}

.article-card:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.article-card__thumb {
  width: 100%;
  height: 180px;
  object-fit: cover;
  background: var(--color-bg-gray);
}

.article-card__body {
  padding: 1.25rem;
}

.article-card__title {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

.article-card__title a {
  color: var(--color-text);
}

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

.article-card__desc {
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-bottom: 0.75rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card__meta {
  font-size: 0.8rem;
  color: var(--color-text-light);
  display: flex;
  gap: 0.75rem;
  align-items: center;
}

.article-card__category {
  background: var(--color-bg-gray);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  font-size: 0.75rem;
}

.section-more {
  text-align: center;
  margin-top: 2rem;
}

/* Category badges */
.category-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.category-badge {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: var(--color-bg-gray);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  color: var(--color-text);
  font-size: 0.9rem;
}

.category-badge:hover {
  background: var(--color-primary);
  color: #fff;
  text-decoration: none;
  border-color: var(--color-primary);
}

/* Single Article */
.article {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 2rem 0 4rem;
}

.article__header {
  margin-bottom: 2rem;
}

.article__title {
  font-size: 1.75rem;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

.article__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.85rem;
  color: var(--color-text-light);
}

.article__category {
  background: var(--color-primary);
  color: #fff;
  padding: 0.15rem 0.6rem;
  border-radius: 4px;
  font-size: 0.8rem;
}

.article__category:hover {
  text-decoration: none;
  background: var(--color-primary-dark);
}

.article__tag {
  color: var(--color-text-light);
  font-size: 0.85rem;
}

.article__thumbnail {
  width: 100%;
  border-radius: 8px;
  margin-bottom: 2rem;
}

/* TOC */
.article__toc {
  background: var(--color-bg-gray);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
}

.article__toc h2 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
}

.article__toc nav ul {
  list-style: none;
  padding-left: 0;
}

.article__toc nav ul li {
  margin-bottom: 0.35rem;
}

.article__toc nav ul ul {
  padding-left: 1.25rem;
}

.article__toc a {
  font-size: 0.9rem;
  color: var(--color-text);
}

/* Article Content */
.article__content {
  font-size: 1rem;
  line-height: 1.9;
}

.article__content h2 {
  font-size: 1.4rem;
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--color-primary);
}

.article__content h3 {
  font-size: 1.15rem;
  margin: 2rem 0 0.75rem;
}

.article__content p {
  margin-bottom: 1.25rem;
}

.article__content ul,
.article__content ol {
  margin-bottom: 1.25rem;
  padding-left: 1.5rem;
}

.article__content li {
  margin-bottom: 0.35rem;
}

.article__content blockquote {
  border-left: 4px solid var(--color-primary);
  padding: 0.75rem 1rem;
  margin: 1.5rem 0;
  background: var(--color-bg-gray);
  color: var(--color-text-light);
}

.article__content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
}

.article__content th,
.article__content td {
  border: 1px solid var(--color-border);
  padding: 0.6rem 0.8rem;
  text-align: left;
}

.article__content th {
  background: var(--color-bg-gray);
  font-weight: 600;
}

/* CTA */
.article__cta {
  margin: 3rem 0 2rem;
  text-align: center;
}

.cta-button {
  display: inline-block;
  background: var(--color-primary);
  color: #fff;
  padding: 0.9rem 2.5rem;
  border-radius: 6px;
  font-size: 1.05rem;
  font-weight: 600;
  transition: background 0.2s;
}

.cta-button:hover {
  background: var(--color-primary-dark);
  text-decoration: none;
  color: #fff;
}

/* Article Navigation */
.article__footer {
  display: flex;
  justify-content: space-between;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
  gap: 1rem;
}

.article__nav {
  font-size: 0.9rem;
  max-width: 45%;
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  margin: 2rem 0;
  list-style: none;
  padding: 0;
}

.page-item a,
.page-item span {
  display: inline-block;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: 0.9rem;
}

.page-item.active span {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 0;
  text-align: center;
  color: var(--color-text-light);
  font-size: 0.85rem;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1rem;
}

.footer-nav a {
  color: var(--color-text-light);
  font-size: 0.85rem;
}

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

/* Static Pages (Privacy / Media) */
.page {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 2rem 0 4rem;
}

.page__header {
  margin-bottom: 2rem;
}

.page__title {
  font-size: 1.75rem;
  line-height: 1.4;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-primary);
}

.page__toc {
  background: var(--color-bg-gray);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
}

.page__toc h2 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
}

.page__toc nav ul {
  list-style: none;
  padding-left: 0;
}

.page__toc nav ul li {
  margin-bottom: 0.35rem;
}

.page__toc nav ul ul {
  padding-left: 1.25rem;
}

.page__toc a {
  font-size: 0.9rem;
  color: var(--color-text);
}

.page__content {
  font-size: 1rem;
  line-height: 1.9;
}

.page__content h2 {
  font-size: 1.4rem;
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--color-primary);
}

.page__content h3 {
  font-size: 1.15rem;
  margin: 2rem 0 0.75rem;
}

.page__content p {
  margin-bottom: 1.25rem;
}

.page__content ul,
.page__content ol {
  margin-bottom: 1.25rem;
  padding-left: 1.5rem;
}

.page__content li {
  margin-bottom: 0.35rem;
}

.page__content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
}

.page__content th,
.page__content td {
  border: 1px solid var(--color-border);
  padding: 0.75rem 1rem;
  text-align: left;
}

.page__content th {
  background: var(--color-bg-gray);
  font-weight: 600;
  white-space: nowrap;
  width: 30%;
}

.page__content strong {
  color: var(--color-text);
}

/* Responsive */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 1.5rem;
  }

  .article-list {
    grid-template-columns: 1fr;
  }

  .article__title {
    font-size: 1.4rem;
  }

  .site-header .container {
    flex-direction: column;
    gap: 0.75rem;
  }

  .article__footer {
    flex-direction: column;
  }

  .article__nav {
    max-width: 100%;
  }
}