:root {
  --paper: #fffef9;      /* 温かい紙色の背景 */
  --ink: #37332C;        /* 本文 */
  --ink-soft: #6E675B;   /* 補足テキスト */
  --line: #E9E2CF;       /* 罫線 */
  --cream: #F8F4E6;      /* パネル背景 */
  --sage: #8FA37E;       /* アクセント（セージ） */
  --sage-soft: #EFF2E6;  /* アクセント淡 */
  --link: #47708C;       /* テキストリンク */
}
html {
  scroll-behavior: smooth;
}
body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.8;
  color: var(--ink);
  background: var(--paper);
  padding: 1rem;
  margin: 0;
}
ul,li {
  list-style: none;
}
img {
  max-width: 100%;
  height: auto;
}
.article {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 2rem;
  @media screen and (max-width: 768px) {
    padding: 0;
  }
}
.article__header {
  display: flex;
  justify-content: center;
  max-width: 720px;
  margin: 0 auto;
  background: #fff;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: 12px;
}
.article__site-title {
  display: flex;
  width: 280px;
}
.article__meta-date {
  font-size: 0.9rem;
  color: var(--ink-soft);
}
.article__title {
  font-size: 1.8rem;
  margin-bottom: 1rem;
  line-height: 1.5;
  text-wrap: pretty;
}
@media screen and (max-width: 768px) {
  .article__site-title {
    width: 220px;
  }
  .article__title {
    margin-top: 1.5rem;
    font-size: 1.4rem;
    line-height: 1.5;
  }
}
.article__lead {
  font-weight: bold;
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.article__date,
.article__note {
  font-size: 0.85rem;
  color: var(--ink-soft);
  margin-bottom: 1rem;
}
.article__toc a {
  color: var(--link);
  /* text-decoration: none; */
  transition: all 0.3s ease;
}

.article__toc a:hover {
  opacity: 0.8;
  text-decoration: underline;
}
.article__section {
  margin-bottom: 2rem;
}
.article__paragraph {
  margin-bottom: 1.2rem;
}
.article__subheading {
  position: relative;
  font-size: 1.4rem;
  margin-top: 2rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.4rem;
}
.article__subheading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 48px;
  height: 2px;
  border-radius: 2px;
  background: var(--sage);
}

.article__list {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.article__list li {
  margin-bottom: 0.5rem;
  list-style-type: disc;
}
/* 番号付きリスト（ordered list） */
.article__list--number {
  padding-left: 1rem;
  margin: 1.5rem 0;
  counter-reset: step-counter;
  list-style: none;
}

.article__list--number li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: 0.75rem;
  line-height: 1.6;
  margin-bottom: 0.5rem;
}

.article__list--number li::before {
  content: counter(step-counter) ".";
  counter-increment: step-counter;
  position: absolute;
  left: 0;
  top: 0;
  font-weight: bold;
  color: #555;
}

iframe {
  max-width: 100%;
  height: auto;
  margin: 1rem 0;
}

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

/* YouTube iframe レスポンシブ対応 */
.article__video-list {
  list-style: none;
  margin: 0;
  padding: 0; 
}
.article__video-list .article__paragraph {
  margin-bottom: 0; 
  text-wrap: pretty;
  text-align: justify;
}
.article__video-wrapper {
  position: relative;
  width: 100%;
  /* max-width: 800px; */
  padding-bottom: 56.25%; /* 16:9比率 */
  height: 0;
  margin-bottom: 2.5rem;
}

.article__video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}
.article__image-block {
  margin: 2rem 0;
  text-align: center;
}
.article__image-block.align-left {
  justify-content: flex-start;
}
.article__image {
  width: 100%;
  height: auto;
  border-radius: 6px;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
  max-width: 100%;
}

/* 小サイズ：600pxまで */
.article__image--small .article__image {
  max-width: 380px;
}

/* 中サイズ：800pxまで（デフォルト相当） */
.article__image--medium .article__image {
  max-width: 500px;
}

/* 大サイズ：1000pxまで */
.article__image--large .article__image {
  max-width: 800px;
}
/* === モバイルサイズ調整（～768px） === */
@media screen and (max-width: 768px) {
  .article__image--small-sp .article__image {
    max-width: 75%;  /* 小：画面幅の90% */
  }
}
.article__caption {
  font-size: 0.85rem;
  color: #666;
  margin-top: 0.5rem;
}

.article__caption a {
  color: #666;
  text-decoration: underline;
}
@media screen and (max-width: 768px) {
  .article__subheading {
    font-size: 1.3rem;
  }
}
.twitter-tweet-block {
  max-width: 340px;
}
@media screen and (max-width: 768px) {
  .twitter-tweet-block {
    width: 95%;
    max-width: 400px;
    margin: 0 auto;
  }
}
/* 紹介アイテムセクション */
.recommended-items {
  margin-top: 3rem;
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 12px;
}

.recommended-items__title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 1.2rem;
  text-align: center;
  color: #333;
}

.recommended-items__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1.5rem;
}

.recommended-item {
  display: flex;
  flex-direction: column;
  background: #fff;
  border-radius: 6px;
  overflow: hidden;
  text-decoration: none;
  color: #333;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.recommended-item:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.recommended-item__image {
  height: 160px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fff;
  padding: 1rem;
}

.recommended-item__image img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.recommended-item__name {
  padding: 0.8rem 1rem;
  font-size: 0.9rem;
  line-height: 1.4;
  flex-grow: 1;
}

.recommended-item__button {
  background: #6B7F5C;
  color: white;
  text-align: center;
  padding: 0.6rem;
  font-size: 0.85rem;
  font-weight: 500;
  transition: background 0.2s ease;
}

.recommended-item:hover .recommended-item__button {
  background: #56684A;
}

/* レスポンシブ対応 */
@media (max-width: 600px) {
  .recommended-items__grid {
    grid-template-columns: 1fr;
  }
  
  .recommended-item__image {
    height: 140px;
  }
}
.related-links {
  margin-top: 2rem;
  margin-bottom: 2rem;
  padding: 1rem 1.25rem;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
}

.related-links__title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.8rem;
}

.related-links__list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  list-style: none;
  padding: 0;
  margin: 0;
}

.related-links__item {

}
.related-links__item a {
  color: var(--ink);
  text-decoration: underline;
  font-size: 0.95rem;
  transition: opacity 0.2s ease;
}
.related-links__item a:hover {
  opacity: 0.7;
}
.author-box {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
  padding: 1rem;
  border-top: 1px solid var(--line);
  font-size: 0.95rem;
  color: var(--ink-soft);
  flex-direction: column;
}
.author-box__heading {
  font-size: 1rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
  color: #333;
}

.author-box__content {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}
.author-box__image {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  object-fit: cover;
  @media (min-width: 467px) {
      width: 84px;
      height: 84px;
    }
}

.author-box__name {
  font-weight: bold;
  margin-top: 0;
  margin-bottom: 0.25rem;
  line-height: 1.5;
}
.author-box__bio {
  margin: 0.25rem 0;
  font-size: 0.85rem;
}
.author-box__link {
  color: #0077cc;
  text-decoration: underline;
  font-size: 0.9rem;
}
.category-links {
  margin: 2rem auto;
  border-radius: 12px;
  max-width: 960px;
  text-align: center;
}
.category-links__list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  justify-content: center;
  gap: 0.5rem;
  list-style: none;
  padding: 0;
  font-size: 0.9rem;
}
@media (min-width: 467px) {
  .category-links__list {
    grid-template-columns: 1fr 1fr 1fr 1fr;
  }
}
.category-links__list li a {
  display: block;
  padding: 0.8rem 1rem;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  text-decoration: none;
  color: var(--ink);
  font-weight: 500;
  transition: 0.2s;
}
.category-links__list li:last-child {
  letter-spacing: -0.03rem;
}
.category-links__list li a:hover {
  background: var(--sage-soft);
  border-color: var(--sage);
}
@media (min-width: 467px) {
  .category-links__list:last-child {
    letter-spacing: 0;
  }
}
/* フッター */
.footer {
  text-align: center;
  padding: 2rem 1rem 1rem;
  font-size: 0.8rem;
  color: var(--ink-soft);
  border-top: 1px solid var(--line);
}
.footer__policy {
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.footer__policy a {
  color: var(--ink-soft);
  text-decoration: underline;
}
.footer__sns {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  align-items: center;
  margin-bottom: 0.5rem;
  list-style: none;
  padding-left: 0;
}

.footer__sns-item a {
  color: #555;
  text-decoration: none;
  font-size: 0.9rem;
  transition: opacity 0.2s ease;

  &:hover {
    opacity: 0.75;
    text-decoration: underline;
    img {
      opacity: 0.75;
    }
  }
}
.footer__sns-icon {
  display: block;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}