:root {
  --color-text: #3f4854;
  --color-heading: #303a45;
  --color-muted: #727b86;
  --color-line: #e4e8ec;
  --color-soft: #f7fafb;
  --color-paper: #ffffff;
  --color-blue: #a9d8ea;
  --color-mint: #bee5d6;
  --color-yellow: #f2df9a;
  --color-gray-accent: #d6dde5;
  --layout-width: 1120px;
  --content-width: 760px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--color-paper);
  color: var(--color-text);
  font-family: "Noto Sans JP", "BIZ UDPGothic", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Meiryo", sans-serif;
  line-height: 1.78;
}

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

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  color: #386f87;
}

a:focus-visible,
button:focus-visible {
  outline: 3px solid rgba(56, 111, 135, 0.35);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: 12px;
  z-index: 20;
  transform: translateY(-160%);
  padding: 8px 12px;
  background: var(--color-heading);
  color: #ffffff;
  font-size: 14px;
  font-weight: 700;
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(var(--layout-width), calc(100% - 40px));
  margin-inline: auto;
}

.narrow-container {
  width: min(var(--content-width), calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  background: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid var(--color-line);
}

.site-header__inner {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  flex: 0 0 auto;
}

.brand__mark {
  width: 31px;
  height: 31px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 3px;
  padding: 4px;
  border: 1px solid #cfd7de;
  background: var(--color-paper);
}

.brand__mark span:nth-child(1) {
  background: var(--color-blue);
}

.brand__mark span:nth-child(2) {
  background: var(--color-line);
}

.brand__mark span:nth-child(3) {
  background: var(--color-mint);
}

.brand__mark span:nth-child(4) {
  background: var(--color-yellow);
}

.brand__body {
  display: grid;
  gap: 1px;
}

.brand__name {
  color: var(--color-heading);
  font-size: 21px;
  font-weight: 750;
  line-height: 1.3;
  letter-spacing: 0;
}

.brand__sub {
  color: var(--color-muted);
  font-size: 11px;
  line-height: 1.3;
}

.global-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 17px;
  color: var(--color-muted);
  font-size: 14px;
  font-weight: 700;
}

.global-nav a[aria-current="page"] {
  color: var(--color-heading);
  text-decoration: underline;
  text-decoration-color: var(--color-blue);
  text-decoration-thickness: 4px;
  text-underline-offset: 7px;
}

.breadcrumbs {
  margin: 0 0 20px;
  color: var(--color-muted);
  font-size: 13px;
}

.breadcrumbs a {
  text-decoration: underline;
  text-decoration-color: var(--color-line);
  text-underline-offset: 4px;
}

.hero {
  padding: 36px 0;
  border-bottom: 1px solid var(--color-line);
}

.hero__inner {
  display: grid;
  grid-template-columns: minmax(320px, 0.82fr) minmax(0, 1.18fr);
  gap: 34px;
  align-items: center;
}

.kicker,
.section-heading p,
.post-meta,
.page-kicker,
.side-block__label {
  color: var(--color-muted);
  font-size: 12px;
  font-weight: 800;
}

.kicker,
.page-kicker {
  width: fit-content;
  margin: 0 0 12px;
  padding: 2px 0 5px;
  border-bottom: 5px solid var(--color-blue);
}

.hero h1,
.page-header h1,
.article-header h1 {
  margin: 0 0 14px;
  color: var(--color-heading);
  font-size: clamp(28px, 3.4vw, 36px);
  line-height: 1.38;
  letter-spacing: 0;
}

.hero__copy > p:last-child,
.page-header__lead,
.article-header__lead {
  margin: 0;
  color: var(--color-muted);
  font-size: 16px;
}

.hero__figure {
  margin: 0;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--color-line);
  background: var(--color-soft);
}

.hero__figure img {
  height: 100%;
  object-fit: cover;
}

.topic-strip {
  border-bottom: 1px solid var(--color-line);
}

.topic-strip__inner {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--color-line);
  border-left: 1px solid var(--color-line);
  border-right: 1px solid var(--color-line);
}

.topic {
  min-height: 58px;
  display: grid;
  place-items: center;
  background: var(--color-paper);
  color: var(--color-heading);
  font-size: 14px;
  font-weight: 800;
  border-top: 4px solid var(--color-gray-accent);
}

.topic--blue,
.category-card--blue {
  border-top-color: var(--color-blue);
}

.topic--mint,
.category-card--mint {
  border-top-color: var(--color-mint);
}

.topic--yellow,
.category-card--yellow {
  border-top-color: var(--color-yellow);
}

.topic--gray,
.category-card--gray {
  border-top-color: var(--color-gray-accent);
}

.section {
  padding: 42px 0;
}

.section--main {
  padding-top: 20px;
}

.section-heading {
  position: relative;
  margin-bottom: 22px;
  padding-bottom: 11px;
  border-bottom: 1px solid var(--color-line);
}

.section-heading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 82px;
  height: 3px;
  background: var(--color-blue);
}

.section-heading p,
.post-meta,
.side-block__label {
  margin: 0;
}

.section-heading h2 {
  margin: 2px 0 0;
  color: var(--color-heading);
  font-size: 24px;
  line-height: 1.4;
  letter-spacing: 0;
}

.featured-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.82fr);
  gap: 28px;
  align-items: center;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--color-line);
}

.featured-card__image,
.post-row__image,
.article-card__image {
  overflow: hidden;
  border: 1px solid var(--color-line);
  background: var(--color-soft);
}

.featured-card__image {
  aspect-ratio: 16 / 9;
}

.post-row__image,
.article-card__image {
  aspect-ratio: 4 / 3;
}

.featured-card__image img,
.post-row__image img,
.article-card__image img {
  height: 100%;
  object-fit: cover;
  transition: transform 0.35s ease;
}

.featured-card__image:hover img,
.post-row__image:hover img,
.article-card__image:hover img {
  transform: scale(1.025);
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 9px 12px;
}

.category-label {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 0 9px;
  color: var(--color-heading);
  background: var(--color-gray-accent);
  font-size: 12px;
  font-weight: 800;
}

.category-label--blue {
  background: var(--color-blue);
}

.category-label--mint {
  background: var(--color-mint);
}

.category-label--yellow {
  background: var(--color-yellow);
}

.category-label--gray {
  background: var(--color-gray-accent);
}

.featured-card h3 {
  margin: 10px 0 12px;
  color: var(--color-heading);
  font-size: 27px;
  line-height: 1.48;
}

.featured-card p:last-child,
.post-row p:last-child,
.side-block p,
.article-card p {
  margin: 0;
  color: var(--color-muted);
}

.content-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 304px;
  gap: 36px;
  align-items: start;
}

.post-list {
  display: grid;
  gap: 22px;
}

.post-row {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: 18px;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--color-line);
}

.post-row h3 {
  margin: 7px 0 7px;
  color: var(--color-heading);
  font-size: 20px;
  line-height: 1.52;
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 26px 22px;
}

.article-card {
  display: grid;
  gap: 12px;
  min-width: 0;
}

.article-card h2,
.article-card h3 {
  margin: 0;
  color: var(--color-heading);
  font-size: 20px;
  line-height: 1.52;
}

.sidebar {
  display: grid;
  gap: 18px;
  padding-top: 20px;
}

.side-block {
  padding: 19px;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
}

.side-block--start {
  background: linear-gradient(180deg, #f9fcfd, var(--color-paper));
  border-top: 5px solid var(--color-blue);
}

.side-block__label {
  width: fit-content;
  margin-bottom: 9px;
  padding-bottom: 4px;
  border-bottom: 4px solid var(--color-blue);
}

.side-block__label--mint {
  border-bottom-color: var(--color-mint);
}

.side-block__label--yellow {
  border-bottom-color: var(--color-yellow);
}

.side-block h2 {
  margin: 0 0 10px;
  color: var(--color-heading);
  font-size: 18px;
  line-height: 1.4;
}

.side-list,
.ranking-list,
.link-list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--color-muted);
  font-size: 14px;
  font-weight: 700;
}

.ranking-list {
  counter-reset: ranking;
}

.ranking-list li {
  counter-increment: ranking;
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 8px;
  align-items: start;
}

.ranking-list li::before {
  content: counter(ranking);
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  background: var(--color-yellow);
  color: var(--color-heading);
  font-size: 12px;
  font-weight: 800;
}

.category-section {
  background: var(--color-soft);
  border-top: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--color-line);
  border: 1px solid var(--color-line);
}

.category-card {
  min-height: 132px;
  display: grid;
  align-content: start;
  gap: 8px;
  padding: 20px;
  background: var(--color-paper);
  border-top: 5px solid var(--color-gray-accent);
}

.category-card span {
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 800;
}

.category-card strong {
  color: var(--color-heading);
  font-size: 18px;
  line-height: 1.5;
}

.page-header,
.article-header {
  padding: 34px 0 28px;
  border-bottom: 1px solid var(--color-line);
}

.page-content,
.article-body {
  padding: 36px 0 56px;
}

.article-hero-image {
  margin: 0 0 28px;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--color-line);
  background: var(--color-soft);
}

.article-hero-image img {
  height: 100%;
  object-fit: cover;
}

.article-photo {
  max-width: 680px;
  margin: 30px auto;
  overflow: hidden;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
}

.article-photo figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--color-line);
  background: var(--color-soft);
  color: var(--color-muted);
  font-size: 13px;
  line-height: 1.6;
}

.prose {
  max-width: var(--content-width);
}

.prose h2 {
  margin: 34px 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-line);
  color: var(--color-heading);
  font-size: 24px;
  line-height: 1.45;
}

.prose h3 {
  margin: 26px 0 10px;
  color: var(--color-heading);
  font-size: 19px;
  line-height: 1.5;
}

.prose p,
.prose li {
  font-size: 17px;
}

.prose p {
  margin: 0 0 18px;
}

.prose ul,
.prose ol {
  margin: 0 0 22px;
  padding-left: 1.4em;
}

.notice {
  margin: 0 0 24px;
  padding: 14px 16px;
  border: 1px solid var(--color-line);
  border-left: 5px solid var(--color-yellow);
  background: #fffdf4;
  color: var(--color-muted);
  font-size: 14px;
}

.data-table {
  margin: 24px 0 28px;
  overflow-x: auto;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
}

.data-table table {
  width: 100%;
  min-width: 460px;
  border-collapse: collapse;
}

.data-table caption {
  padding: 14px 16px;
  border-bottom: 1px solid var(--color-line);
  background: var(--color-soft);
  color: var(--color-heading);
  font-size: 15px;
  font-weight: 800;
  text-align: left;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--color-line);
  font-size: 15px;
  line-height: 1.5;
  text-align: left;
}

.data-table th {
  background: #f7faf8;
  color: var(--color-heading);
  font-weight: 800;
}

.data-table tr:last-child td {
  border-bottom: 0;
}

.data-table td:last-child,
.data-table th:last-child {
  text-align: right;
  white-space: nowrap;
}

.table-note {
  margin-top: -14px;
  color: var(--color-muted);
  font-size: 13px;
}

.code-diagram {
  max-width: 520px;
  margin: 24px auto 28px;
  padding: 18px;
  border: 1px solid var(--color-line);
  border-left: 5px solid var(--color-blue);
  background: var(--color-soft);
}

.code-diagram__caption {
  margin: 0 0 14px;
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 800;
}

.code-tree,
.code-tree ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.code-tree li {
  position: relative;
  margin: 0;
  padding: 0 0 0 24px;
}

.code-tree > li {
  padding-left: 0;
}

.code-tree ul {
  margin-top: 10px;
  margin-left: 16px;
  padding-left: 22px;
  border-left: 1px solid #cdd8df;
}

.code-tree ul li::before {
  content: "";
  position: absolute;
  top: 17px;
  left: 0;
  width: 16px;
  border-top: 1px solid #cdd8df;
}

.code-tree__node {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 5px;
  align-items: center;
  max-width: 100%;
  padding: 8px 10px;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
  color: var(--color-heading);
  font-family: "Consolas", "Monaco", monospace;
  font-size: 14px;
  line-height: 1.4;
}

.code-tree__tag {
  font-weight: 800;
}

.code-tree__class {
  color: #386f87;
}

.affiliate-box {
  margin: 34px 0 28px;
  padding: 20px;
  border: 1px solid var(--color-line);
  border-top: 5px solid var(--color-mint);
  background: var(--color-soft);
}

.affiliate-box--blue {
  border-top-color: var(--color-blue);
}

.affiliate-box--yellow {
  border-top-color: var(--color-yellow);
}

.affiliate-box__label {
  width: fit-content;
  margin: 0 0 8px;
  padding-bottom: 4px;
  border-bottom: 4px solid var(--color-mint);
  color: var(--color-muted);
  font-size: 12px;
  font-weight: 800;
}

.affiliate-box--blue .affiliate-box__label {
  border-bottom-color: var(--color-blue);
}

.affiliate-box--yellow .affiliate-box__label {
  border-bottom-color: var(--color-yellow);
}

.affiliate-box h2 {
  margin-top: 0;
}

.affiliate-list {
  display: grid;
  gap: 12px;
  margin: 18px 0 0;
}

.affiliate-item {
  display: grid;
  gap: 6px;
  padding: 15px;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
}

.affiliate-item strong {
  color: var(--color-heading);
  font-size: 17px;
  line-height: 1.5;
}

.affiliate-item p {
  margin: 0;
  color: var(--color-muted);
  font-size: 15px;
}

.affiliate-link {
  width: fit-content;
  margin-top: 4px;
  color: #386f87;
  font-size: 14px;
  font-weight: 800;
  text-decoration: underline;
  text-decoration-color: var(--color-blue);
  text-underline-offset: 4px;
}

.affiliate-link--pending {
  color: var(--color-muted);
  text-decoration-color: var(--color-line);
}

.affiliate-note {
  margin: 16px 0 0;
  color: var(--color-muted);
  font-size: 13px;
}

.reading-order {
  display: grid;
  gap: 14px;
  margin: 24px 0;
  padding: 0;
  list-style: none;
  counter-reset: steps;
}

.reading-order li {
  counter-increment: steps;
  display: grid;
  grid-template-columns: 36px minmax(0, 1fr);
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--color-line);
  background: var(--color-paper);
}

.reading-order li::before {
  content: counter(steps);
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  background: var(--color-blue);
  color: var(--color-heading);
  font-weight: 800;
}

.site-footer {
  padding: 32px 0;
  background: #f1f4f6;
  border-top: 1px solid var(--color-line);
}

.site-footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 700;
}

.site-footer p {
  margin: 0;
  color: var(--color-heading);
  font-weight: 750;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

@media (max-width: 900px) {
  .site-header__inner,
  .site-footer__inner {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    padding: 18px 0;
  }

  .global-nav {
    justify-content: flex-start;
  }

  .hero__inner,
  .featured-card,
  .content-layout {
    grid-template-columns: 1fr;
  }

  .topic-strip__inner,
  .category-grid,
  .article-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .prose p,
  .prose li {
    font-size: 16px;
  }
}

@media (max-width: 560px) {
  .container,
  .narrow-container {
    width: min(100% - 28px, var(--layout-width));
  }

  .brand__name {
    font-size: 18px;
  }

  .brand__sub {
    display: none;
  }

  .hero {
    padding: 28px 0 34px;
  }

  .hero__inner {
    gap: 22px;
  }

  .hero h1,
  .page-header h1,
  .article-header h1 {
    font-size: 27px;
  }

  .featured-card h3 {
    font-size: 22px;
  }

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

  .topic-strip__inner,
  .category-grid,
  .article-grid {
    grid-template-columns: 1fr;
  }

  .category-card {
    min-height: 104px;
  }
}

/* --- WordPressテーマ用の補完スタイル（元サイトに無い要素） --- */
.pagination { margin-top: 2rem; }
.pagination .nav-links { display: flex; flex-wrap: wrap; gap: .5rem; justify-content: center; }
.pagination .page-numbers {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 2.4rem; padding: .4rem .7rem; border: 1px solid var(--color-line);
  border-radius: 8px; color: var(--color-heading); text-decoration: none; background: var(--color-paper);
}
.pagination .page-numbers.current { background: var(--color-blue); border-color: var(--color-blue); }
.pagination .page-numbers:hover { background: var(--color-soft); }
.wp-caption, figure.wp-caption { max-width: 100%; }
.screen-reader-text { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(1px,1px,1px,1px); white-space: nowrap; }