/* =========================================================
   base.css — 全ページ共通（案B）
   設計値／リセット／スキップリンク／ヘッダー／メニュー／フッター／表示アニメ
   ヘッダーとフッターの HTML は全ページ同じ雛形（リンク先の階層と aria-current だけが違う）
   ========================================================= */

:root {
  /* 色：墨・生成り・紙白＋文字色 */
  --ink: #111110;
  --kinari: #f3f1ea;
  --paper-white: #fff;
  --text: #2b2a27;
  --sub: #5c5a54;
  --rule: #d9d6cc;
  --on-ink: rgba(243, 241, 234, .82);
  --on-ink-sub: rgba(243, 241, 234, .66);
  --on-ink-line: rgba(243, 241, 234, .2);

  /* 書体 */
  --mincho: "Zen Old Mincho", "Yu Mincho", "YuMincho", "Hiragino Mincho ProN", serif;
  --sans: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  --bodoni: "Bodoni Moda", "Didot", "Bodoni 72", Georgia, serif;
  --logo: Arial, "Helvetica Neue", sans-serif;

  /* グリッド：外側余白 --gx、内容幅の上限 1312px（82rem）。左右の余白は全セクション --wrap */
  --gx: clamp(1.25rem, 4.45vw, 4rem);
  --cg: 1.5rem;
  --wrap: max(var(--gx), calc((100% - 82rem) / 2));
  --header-h: 4rem;

  /* 折り線（一点鎖線）：background-size 19px で使う */
  --fold: linear-gradient(to right, var(--ink) 0 46%, transparent 46% 66%, var(--ink) 66% 72%, transparent 72%);
  --fold-v: linear-gradient(to bottom, var(--ink) 0 46%, transparent 46% 66%, var(--ink) 66% 72%, transparent 72%);
}

/* ---------- リセット ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; background: var(--kinari); }

body {
  margin: 0;
  color: var(--ink);
  background: var(--kinari);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
p, h1, h2, h3, figure { margin-top: 0; }
button { font: inherit; }

/* ---------- スキップリンク（フォーカス時だけ表示） ---------- */
.skip-link {
  position: fixed;
  z-index: 1000;
  top: .5rem;
  left: .5rem;
  padding: .75rem 1rem;
  color: var(--ink);
  background: var(--paper-white);
  outline: 2px solid var(--ink);
  white-space: nowrap;
  clip-path: inset(50%);
}

.skip-link:focus { clip-path: none; }

/* ---------- 画面には出さず、読み上げだけに使う文字（カルーセルの「01 / 04」など） ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- ロゴ（ヘッダー・フッター共通） ---------- */
.logo {
  display: inline-flex;
  align-items: center;
  gap: .42rem;
  font-family: var(--logo);
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -.07em;
  white-space: nowrap;
}

.logo__mark {
  display: inline-block;
  padding: .27em .16em .22em;
  color: var(--ink);
  background: var(--paper-white);
  letter-spacing: -.05em;
}

/* ---------- ヘッダー ---------- */
.site-header {
  position: fixed;
  z-index: 100;
  inset: 0 0 auto;
  height: var(--header-h);
  color: var(--paper-white);
  background: var(--ink);
  transition: height .25s ease;
}

.site-header.is-scrolled { height: 3.5rem; }

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  padding-inline: var(--wrap);
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.5vw, 2.8rem);
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav__link {
  position: relative;
  display: block;
  padding: .5rem 0;
  font-size: .8125rem;
  font-weight: 500;
  letter-spacing: .06em;
}

.site-nav__link::after {
  position: absolute;
  right: 0;
  bottom: .18rem;
  left: 0;
  height: 1px;
  background: currentColor;
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform .25s ease;
}

.site-nav__link:hover::after,
.site-nav__link:focus-visible::after,
.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  transform-origin: left;
}

.menu-toggle {
  display: none;
  width: 2.5rem;
  height: 2.5rem;
  padding: .65rem .35rem;
  border: 0;
  color: inherit;
  background: transparent;
  cursor: pointer;
}

.menu-toggle i {
  display: block;
  height: 1px;
  margin: .38rem 0;
  background: currentColor;
  transition: transform .25s ease;
}

.menu-toggle[aria-expanded="true"] i:first-child { transform: translateY(.22rem) rotate(45deg); }
.menu-toggle[aria-expanded="true"] i:last-child { transform: translateY(-.22rem) rotate(-45deg); }

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

.site-footer__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem 2.5rem;
  padding: 3rem var(--wrap) 1.5rem;
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1.25rem;
}

.site-footer .logo { font-size: 1.5rem; }

.site-footer__sns {
  display: inline-flex;
  align-items: center;
  gap: .65rem;
  font-size: .8125rem;
  letter-spacing: .08em;
}

.site-footer__sns img { width: 1.15rem; height: 1.15rem; object-fit: contain; }

.site-footer__nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.site-footer__label {
  margin: 0 0 1.1rem;
  color: var(--on-ink-sub);
  font-family: var(--bodoni);
  font-size: .75rem;
  font-weight: 500;
  letter-spacing: .2em;
}

.site-footer__list {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: .5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-footer__list li { line-height: 0; }
.site-footer__list a { display: inline-block; font-size: .875rem; line-height: 1.6; }
.site-footer__list a:hover { opacity: .6; }

.site-footer__copy {
  grid-column: 1 / -1;
  margin: .5rem 0 0;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(243, 241, 234, .14);
  color: var(--on-ink-sub);
  font-size: .75rem;
  letter-spacing: .12em;
}

/* ---------- 表示アニメ ---------- */
.reveal { opacity: 0; transform: translateY(1.5rem); transition: opacity .7s ease, transform .7s ease; }
.reveal.is-visible { opacity: 1; transform: none; }

/* ---------- ≤900：メニュー ---------- */
@media (max-width: 900px) {
  .site-header.is-scrolled { height: var(--header-h); }
  .menu-toggle { display: block; }

  .site-nav {
    position: fixed;
    inset: var(--header-h) 0 0;
    padding: 3rem var(--wrap);
    background: var(--ink);
    visibility: hidden;
    opacity: 0;
    transition: opacity .2s ease, visibility .2s ease;
  }

  .site-nav.is-open { visibility: visible; opacity: 1; }
  .site-nav__list { flex-direction: column; align-items: stretch; gap: 0; }

  .site-nav__link {
    padding: 1.15rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, .18);
    font-size: 1rem;
    letter-spacing: .04em;
  }

  .site-nav__link::after { content: none; }
  html.menu-open { overflow: hidden; }

  .site-footer__inner { grid-template-columns: 1fr; }
}

/* ---------- ≤620：フッター ---------- */
@media (max-width: 620px) {
  .site-footer__inner { gap: 1.75rem; padding-top: 2.5rem; }
  .site-footer__brand { flex-direction: row; align-items: center; justify-content: space-between; }
  .site-footer__nav { gap: 1rem; }
  .site-footer__copy { margin-top: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}