/* ============================================================
   Project NOVA 文庫 — storefront.css （index 専用）
   ============================================================ */

/* ---- hero（レーベルの主張＝thesis） ---- */
.hero {
  position: relative;
  padding-block: clamp(3.4rem, 9vw, 7rem) clamp(2.6rem, 6vw, 4.4rem);
  overflow: clip;
}
.hero__glow {
  position: absolute; z-index: -1; pointer-events: none;
  width: 46rem; height: 46rem; top: -22rem; right: -14rem;
  background: radial-gradient(closest-side, var(--accent-faint), transparent 72%);
}
.hero__star {
  position: absolute; z-index: -1; pointer-events: none;
  width: clamp(11rem, 30vw, 22rem); height: auto; top: 6%; right: -2rem;
  color: var(--accent); opacity: .07;
  animation: nova-drift 26s var(--ease) infinite alternate;
}
@keyframes nova-drift {
  from { transform: translateY(0) rotate(0deg); }
  to   { transform: translateY(2.2rem) rotate(8deg); }
}
.hero__eyebrow { margin-bottom: 1.5rem; }
.hero h1 {
  font-size: clamp(2.1rem, 1.2rem + 4.4vw, 4.1rem);
  line-height: 1.32; letter-spacing: .04em;
  max-width: 20ch; text-wrap: balance;
}
.hero h1 .accent { color: var(--accent); }
.hero__lead {
  margin-top: 1.6rem; max-width: 38rem;
  font-size: clamp(1.02rem, .5vw + .95rem, 1.22rem);
  color: var(--text-muted); line-height: 2;
}
.hero__meta {
  margin-top: 2rem; display: flex; flex-wrap: wrap; gap: .5rem 1.4rem;
  font-family: var(--font-sans); font-size: .82rem; letter-spacing: .12em;
  color: var(--text-muted);
}
.hero__meta b { color: var(--text); font-weight: 700; }

/* ---- section head ---- */
.section-head {
  display: flex; align-items: baseline; justify-content: space-between; gap: 1rem;
  border-top: 1px solid var(--hairline);
  padding-top: 1.5rem; margin-bottom: clamp(1.8rem, 4vw, 2.8rem);
}
.section-head h2 {
  font-size: clamp(1.25rem, .6vw + 1.1rem, 1.6rem); letter-spacing: .08em;
}
.section-head .latin { color: var(--text-muted); font-size: .82rem; }

/* ---- catalog grid ---- */
.catalog {
  display: grid; gap: clamp(1.4rem, 3.5vw, 2.6rem) clamp(1rem, 3vw, 2rem);
  /* スマホで自然に2列、画面が広がるほど列が増える（メディアクエリ不要・堅牢） */
  grid-template-columns: repeat(auto-fill, minmax(min(47%, 15rem), 1fr));
  padding-bottom: clamp(3rem, 7vw, 5rem);
}

/* ---- book card ---- */
.book-card {
  display: flex; flex-direction: column;
  color: inherit;
}
.book-card__art {
  position: relative; aspect-ratio: 1600 / 2560; border-radius: var(--radius-sm);
  overflow: hidden; background: var(--surface-2);
  box-shadow: var(--shadow);
  transition: transform .4s var(--ease), box-shadow .4s var(--ease);
}
.book-card__art img { width: 100%; height: 100%; object-fit: cover; }
.book-card__art .keyart { width: 100%; height: 100%; border-radius: 0; }
.book-card__art::after {                /* アクセントの下罫（フォーカス/ホバーで伸びる） */
  content: ""; position: absolute; left: 0; bottom: 0; height: 3px; width: 0;
  background: var(--accent); transition: width .45s var(--ease);
}
.book-card:hover .book-card__art,
.book-card:focus-visible .book-card__art { transform: translateY(-6px); box-shadow: var(--shadow-lift); }
.book-card:hover .book-card__art::after,
.book-card:focus-visible .book-card__art::after { width: 100%; }
.book-card:focus-visible { outline: none; }
.book-card:focus-visible .book-card__art { outline: 2px solid var(--accent); outline-offset: 4px; }

.book-card__body { padding-top: 1.1rem; }
.book-card__num {
  font-family: var(--font-sans); font-weight: 500; font-size: .72rem;
  letter-spacing: .22em; color: var(--accent); display: block; margin-bottom: .5rem;
}
.book-card__title {
  font-size: clamp(1.15rem, .5vw + 1.05rem, 1.4rem); line-height: 1.4;
  letter-spacing: .04em; margin-bottom: .4rem;
}
.book-card__genre {
  font-family: var(--font-sans); font-size: .76rem; letter-spacing: .08em;
  color: var(--text-muted); margin-bottom: .7rem;
}
.book-card__hook { font-size: .95rem; line-height: 1.85; color: var(--text); }
.book-card__more {
  margin-top: .85rem; font-family: var(--font-sans); font-size: .82rem;
  letter-spacing: .08em; color: var(--accent);
  display: inline-flex; align-items: center; gap: .4em;
}
.book-card__more svg { width: .9em; height: .9em; transition: transform .3s var(--ease); }
.book-card:hover .book-card__more svg { transform: translateX(.25em); }

/* ---- 余白の散文（レーベルの言葉・閉じ） ---- */
.creed {
  border-top: 1px solid var(--hairline);
  padding-block: clamp(3rem, 7vw, 5rem);
  display: grid; gap: 1.4rem; max-width: var(--reading);
}
.creed p { font-size: clamp(1.05rem, .5vw + .98rem, 1.25rem); line-height: 2.1; }
.creed .lead-in { color: var(--accent); font-family: var(--font-sans); font-size: .78rem; letter-spacing: .22em; }