:root {
  --ink: #241711;
  --muted: #6f625d;
  --line: #eadfd9;
  --soft: #fff8f3;
  --red: #bf0000;
  --red-dark: #930000;
  --orange: #f36f21;
  --cream: #fff2e7;
  --white: #fff;
  --shadow: 0 18px 48px rgba(83, 42, 20, 0.1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--white); font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", Meiryo, sans-serif; line-height: 1.75; }
a { color: var(--red-dark); text-underline-offset: .18em; }
.pr-bar { padding: 12px 20px; border-bottom: 1px solid #f0d0c7; background: #fff1ed; color: #633025; font-size: .92rem; }
.site-nav { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid var(--line); background: rgba(255,255,255,.96); backdrop-filter: blur(12px); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; width: min(1180px, calc(100% - 40px)); min-height: 60px; margin: 0 auto; gap: 24px; }
.brand { color: var(--ink); font-weight: 900; text-decoration: none; white-space: nowrap; }
.nav-links { display: flex; gap: 20px; overflow-x: auto; white-space: nowrap; font-size: .9rem; }
.nav-links a { color: #4c3e38; text-decoration: none; }
.nav-links a[aria-current="page"] { color: var(--red); font-weight: 800; }
.rakuten-hero { overflow: hidden; border-bottom: 1px solid var(--line); background: radial-gradient(circle at 85% 20%, rgba(243,111,33,.2), transparent 28%), linear-gradient(135deg, #fff 0%, #fff5ee 58%, #ffe4d2 100%); }
.hero-inner, .section-inner { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.hero-inner { padding: 76px 0 62px; }
.eyebrow { margin: 0 0 12px; color: var(--red); font-size: .82rem; font-weight: 900; letter-spacing: .12em; text-transform: uppercase; }
h1, h2, h3 { margin-top: 0; line-height: 1.35; }
h1 { max-width: 820px; margin-bottom: 18px; font-size: clamp(2.3rem, 5vw, 4.5rem); letter-spacing: -.03em; }
h1 span { color: var(--red); }
.lead { max-width: 760px; color: #594943; font-size: 1.1rem; }
.hero-stats { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.hero-stats div { min-width: 130px; padding: 14px 18px; border: 1px solid #f0d0c0; border-radius: 14px; background: rgba(255,255,255,.78); }
.hero-stats strong, .hero-stats span { display: block; }
.hero-stats strong { color: var(--red); font-size: 1.5rem; }
.hero-stats span, .updated-at { color: var(--muted); font-size: .88rem; }
.updated-at { margin-top: 18px; }
main section { padding: 68px 0; }
.intro-section, .ranking-section { background: var(--soft); }
.important-note { padding: 26px 28px; border: 1px solid #f0d3c3; border-left: 6px solid var(--orange); border-radius: 14px; background: var(--white); box-shadow: var(--shadow); }
.important-note h2 { margin-bottom: 8px; }
.important-note p:last-child { margin-bottom: 0; }
.section-heading { max-width: 720px; margin-bottom: 28px; }
.section-heading h2, .source-grid h2 { margin-bottom: 10px; font-size: clamp(1.6rem, 3vw, 2.25rem); }
.featured-grid, .product-grid { display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); gap: 18px; }
.product-card { display: flex; min-width: 0; flex-direction: column; padding: 20px; border: 1px solid var(--line); border-radius: 16px; background: var(--white); box-shadow: 0 8px 26px rgba(83,42,20,.06); }
.featured-card { border-color: #efbd9f; box-shadow: var(--shadow); }
.product-card__top { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-bottom: 16px; }
.rank-badge { display: inline-flex; align-items: baseline; gap: 2px; color: var(--red); font-size: 1.7rem; font-weight: 900; }
.rank-badge small { font-size: .78rem; }
.category-badge { overflow: hidden; max-width: 70%; padding: 4px 9px; border-radius: 999px; background: var(--cream); color: #8a3a18; font-size: .72rem; font-weight: 800; text-overflow: ellipsis; white-space: nowrap; }
.product-card h3 { margin-bottom: 8px; font-size: 1.05rem; }
.shop-name { margin: 0 0 6px; color: var(--muted); font-size: .82rem; }
.product-price { margin: 0 0 14px; color: var(--red); font-size: 1.15rem; font-weight: 900; }
.product-card > p:not(.shop-name):not(.product-price) { color: #584943; font-size: .9rem; }
.use-case { margin: auto 0 16px; padding: 12px; border-radius: 10px; background: var(--soft); font-size: .84rem; }
.use-case strong, .use-case span { display: block; }
.use-case strong { color: #8a3a18; }
.rakuten-button { display: block; padding: 11px 14px; border-radius: 10px; background: var(--red); color: var(--white); font-weight: 800; text-align: center; text-decoration: none; }
.rakuten-button:hover { background: var(--red-dark); }
.ranking-tools { display: grid; gap: 18px; margin-bottom: 18px; padding: 20px; border: 1px solid var(--line); border-radius: 14px; background: var(--white); }
.search-box span { display: block; margin-bottom: 6px; font-size: .86rem; font-weight: 800; }
.search-box input { width: 100%; min-height: 48px; padding: 10px 14px; border: 1px solid #d8c8c0; border-radius: 10px; font: inherit; }
.filter-buttons { display: flex; flex-wrap: wrap; gap: 8px; }
.filter-button { padding: 7px 12px; border: 1px solid #dfc9bd; border-radius: 999px; background: var(--white); color: #6a4031; cursor: pointer; }
.filter-button.active { border-color: var(--red); background: var(--red); color: var(--white); }
.result-count { color: var(--muted); font-size: .9rem; }
.product-card.is-hidden { display: none; }
.load-more { display: block; min-width: 240px; margin: 28px auto 0; padding: 13px 20px; border: 1px solid var(--red); border-radius: 10px; background: var(--white); color: var(--red); font: inherit; font-weight: 800; cursor: pointer; }
.source-section { border-top: 1px solid var(--line); }
.source-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 32px; }
footer { padding: 34px 20px; background: #2b1912; color: #eadbd3; text-align: center; font-size: .9rem; }
footer a { color: #ffd0b2; }

@media (max-width: 980px) { .featured-grid, .product-grid { grid-template-columns: repeat(2,minmax(0,1fr)); } }
@media (max-width: 620px) {
  .nav-inner { min-height: auto; align-items: flex-start; flex-direction: column; gap: 6px; padding: 10px 0; }
  .nav-links { width: 100%; }
  .hero-inner, .section-inner { width: calc(100% - 28px); }
  .hero-inner { padding: 52px 0 44px; }
  main section { padding: 48px 0; }
  .featured-grid, .product-grid, .source-grid { grid-template-columns: 1fr; }
  .important-note { padding: 20px; }
}