:root {
  --text: #222;
  --muted: #555;
  --link: #1a6ed8;
  --line: #e5e5e5;
  --bg: #fff;
  --bg-soft: #f6f8fa;
  --width: 1120px;
  --narrow: 840px;
}

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

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

body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font-family: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  font-size: 15px;
  line-height: 1.8;
  overflow-wrap: anywhere;
}

a {
  color: var(--link);
}

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

h1,
h2,
h3 {
  font-weight: 900;
  line-height: 1.4;
}

/* ---- ヘッダー ---- */
.site-header {
  border-bottom: 1px solid var(--line);
  background: #fff;
}

.site-header__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding: 16px 20px;
}

.site-title {
  color: var(--text);
  font-size: 18px;
  font-weight: 900;
  letter-spacing: 0.04em;
  text-decoration: none;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 20px;
}

.site-nav a {
  color: var(--text);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* ---- 本文 ---- */
main {
  padding-bottom: 80px;
}

.container {
  max-width: var(--width);
  margin: 0 auto;
  padding: 48px 20px 0;
}

.container.narrow {
  max-width: var(--narrow);
}

.page-heading {
  margin: 0 0 32px;
  font-size: 32px;
}

.lead-heading {
  margin: 0 0 32px;
  font-size: 34px;
}

.section-heading {
  margin: 0 0 20px;
  font-size: 28px;
}

.container h2 {
  margin: 40px 0 12px;
  font-size: 22px;
}

.container h2.small-heading {
  margin: 24px 0 4px;
  font-size: 15px;
}

.container h3 {
  margin: 28px 0 8px;
  font-size: 17px;
}

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

.figure {
  text-align: center;
}

/* ---- トップのヒーロー ---- */
.hero {
  background: url("/images/hero-bg.webp") center / cover no-repeat;
}

.hero img {
  display: block;
  width: 100%;
  max-width: 1600px;
  margin: 0 auto;
}

/* ---- お知らせ一覧 ---- */
.news-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.news-list a {
  display: block;
  padding: 20px 56px 20px 24px;
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: 0 2px 6px rgb(0 0 0 / 8%);
  color: var(--text);
  text-decoration: none;
  position: relative;
}

.news-list a::after {
  content: "→";
  position: absolute;
  right: 24px;
  bottom: 16px;
  font-size: 20px;
}

.news-list a:hover {
  background: var(--bg-soft);
}

.news-list time {
  display: block;
  font-size: 13px;
  font-weight: 700;
}

.news-list span {
  display: block;
  font-size: 19px;
  font-weight: 900;
  line-height: 1.5;
}

/* ---- お知らせ記事 ---- */
.article-header {
  margin-bottom: 32px;
}

.article-header h1 {
  margin: 0 0 16px;
  font-size: 30px;
}

.article-subtitle {
  margin: 0 0 16px;
  font-size: 19px;
  text-align: center;
}

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

.article-issuer {
  margin: 16px 0 0;
  font-size: 13px;
  font-weight: 700;
  text-align: right;
}

.article blockquote {
  margin: 24px 0;
  padding: 4px 20px;
  border-left: 4px solid var(--line);
}

.back-to-list {
  margin-top: 48px;
}

/* ---- リンク・ボタン ---- */
.link-list {
  margin: 24px 0;
  padding: 0;
  list-style: none;
}

.link-list li {
  margin: 6px 0;
}

.button {
  display: inline-block;
  padding: 12px 32px;
  border-radius: 999px;
  background: var(--link);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
}

.link-guide {
  max-width: 720px;
  margin: 56px auto 0;
  padding: 16px 24px;
  border: 1px solid #999;
  font-size: 14px;
}

.link-guide__url {
  font-size: 15px;
}

.link-guide__url strong {
  font-size: 20px;
  text-decoration: underline;
}

.contact-box {
  margin: 24px 0;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: 0 2px 6px rgb(0 0 0 / 8%);
  text-align: center;
}

.contact-box p {
  margin: 0;
}

.contact-box__mail {
  font-size: 22px;
  font-weight: 700;
}

/* ---- フッター ---- */
.site-footer {
  border-top: 1px solid var(--line);
}

.site-footer__inner {
  max-width: var(--width);
  margin: 0 auto;
  padding: 40px 20px 64px;
  font-size: 14px;
}

.footer-heading {
  margin: 24px 0 8px;
  font-size: 15px;
  font-weight: 900;
}

.sponsors {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 40px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.sponsors img {
  display: block;
  width: 200px;
}

.partners {
  display: flex;
  flex-wrap: wrap;
  margin: 0;
  padding: 0;
  list-style: none;
  font-weight: 700;
}

.partners li + li::before {
  content: "｜";
  margin: 0 8px;
}

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

.contact-address {
  margin-top: 24px;
  font-style: normal;
}

.footer-links {
  margin-top: 16px;
  font-size: 13px;
}

@media (max-width: 768px) {
  body {
    font-size: 14px;
  }

  .site-header__inner {
    padding: 12px 16px;
  }

  .site-nav {
    gap: 4px 14px;
  }

  .container {
    padding: 32px 16px 0;
  }

  .page-heading,
  .article-header h1 {
    font-size: 24px;
  }

  .lead-heading {
    font-size: 24px;
  }

  .section-heading {
    font-size: 22px;
  }

  .container h2 {
    font-size: 19px;
  }

  .news-list span {
    font-size: 16px;
  }

  .link-guide {
    padding: 12px 16px;
  }

  .site-footer__inner {
    padding: 32px 16px 48px;
  }

  .sponsors img {
    width: 160px;
  }
}