/* 基本設定：サイト全体の読みやすさを整えます */
:root {
  --color-text: #2f261d;
  --color-muted: #7a6a5d;
  --color-border: #e2e2e2;
  --color-border-soft: #eeeeee;
  --color-bg: #ffffff;
  --color-soft: #f5f5f5;
  --color-accent: #f28c28;
  --color-accent-dark: #d86500;
  --color-title-bg: #ffffff;
  --color-nav-bar: #F4E511;
  --color-panel: #f6f6f6;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: #ffffff;
  color: var(--color-text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.7;
}

img {
  display: block;
  max-width: 100%;
}

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

a:hover,
a:focus {
  text-decoration: underline;
}

.container {
  width: min(1040px, calc(100% - 40px));
  margin: 0 auto;
}

/* ヘッダーとナビゲーション */
.site-header {
  background: var(--color-title-bg);
  text-align: center;
}

.site-header .container {
  padding: 38px 0 26px;
}

.site-title {
  display: inline-block;
  color: #d96f12;
  font-size: clamp(2.35rem, 6vw, 4.4rem);
  font-weight: 900;
  letter-spacing: 0;
  line-height: 1.2;
}

.site-title:hover {
  text-decoration: none;
}

.site-tagline {
  margin: 10px 0 0;
  color: var(--color-muted);
  font-size: 1.02rem;
}

.global-nav {
  position: sticky;
  top: 0;
  z-index: 10;
  border-top: 0;
  border-bottom: 0;
  background: var(--color-nav-bar);
}

.nav-inner {
  display: flex;
  justify-content: center;
  gap: 0;
  overflow-x: auto;
  padding: 0;
  scrollbar-width: thin;
}

.nav-inner a {
  flex: 0 0 auto;
  border-left: 1px solid rgba(47, 38, 29, 0.18);
  border-radius: 0;
  color: var(--color-text);
  font-weight: 700;
  min-width: 132px;
  padding: 14px 18px;
  text-align: center;
}

.nav-inner a:last-child {
  border-right: 1px solid rgba(47, 38, 29, 0.18);
}

.nav-inner a:hover,
.nav-inner a:focus,
.nav-inner a[aria-current="page"] {
  background: #ffffff;
  color: var(--color-accent-dark);
  text-decoration: none;
}

.nav-inner a[aria-current="page"] {
  font-weight: 900;
}

.nav-inner a:hover,
.nav-inner a:focus {
  background: #fff0df;
  color: var(--color-accent-dark);
  text-decoration: none;
}

.nav-inner a[aria-current="page"]:hover,
.nav-inner a[aria-current="page"]:focus {
  background: #ffffff;
}

/* ページ共通レイアウト */
.page-layout {
  padding: 24px 0 64px;
}

.section-heading {
  display: flex;
  align-items: baseline;
  justify-content: flex-start;
  gap: 16px;
  margin-bottom: 18px;
}

.section-heading > a {
  flex: 0 0 auto;
  font-size: 0.92rem;
  font-weight: 800;
}

.section-heading h1,
.section-heading h2,
.page-head h1 {
  margin: 0;
  font-size: 1.45rem;
  line-height: 1.35;
}

.page-head {
  border-bottom: 1px solid var(--color-border-soft);
  margin-bottom: 24px;
  padding-bottom: 18px;
}

.page-head p {
  margin: 8px 0 0;
  color: var(--color-muted);
}

.price-note {
  margin: 0 0 12px;
  color: var(--color-muted);
  font-size: 0.88rem;
}

/* セール一覧ボックス */
.sale-box {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-panel);
  margin-bottom: 18px;
  padding: 16px 24px 18px;
}

.sale-box .section-heading,
.book-showcase .section-heading {
  margin-bottom: 10px;
}

.sale-list {
  display: grid;
  gap: 4px;
  margin: 0;
  padding-left: 1.35em;
  font-size: 1.05rem;
  line-height: 1.45;
}

.sale-list a {
  font-weight: 700;
}

.sale-list-period {
  margin-left: 6px;
}

/* 横スクロールの表紙カード */
.book-showcase {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-panel);
  margin-bottom: 24px;
  padding: 16px 24px 8px;
}

.book-scroll {
  display: grid;
  grid-auto-columns: minmax(150px, 174px);
  grid-auto-flow: column;
  gap: 16px;
  overflow-x: auto;
  padding: 2px 2px 14px;
  scroll-snap-type: x proximity;
  scrollbar-width: thin;
}

.cover-only-scroll {
  grid-auto-columns: minmax(116px, 132px);
  gap: 12px;
}

.book-card,
.cover-only-card {
  display: flex;
  flex-direction: column;
  min-height: 100%;
  border: 1px solid var(--color-border-soft);
  border-radius: 8px;
  background: #ffffff;
  overflow: hidden;
  scroll-snap-align: start;
}

.cover-only-card {
  aspect-ratio: 3 / 4;
}

.cover-only-card:hover,
.cover-only-card:focus {
  border-color: var(--color-accent);
  text-decoration: none;
  transform: translateY(-2px);
}

.cover-only-card .cover-wrap {
  height: 100%;
}

.cover-wrap {
  display: grid;
  place-items: center;
  aspect-ratio: 3 / 4;
  background: #ffffff;
}

.cover-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.placeholder-cover {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  padding: 16px;
  color: var(--color-muted);
  font-weight: 800;
  font-size: 1.12rem;
  text-align: center;
}

.book-body {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 6px;
  padding: 12px;
}

.book-title {
  margin: 0;
  font-size: 0.98rem;
  line-height: 1.45;
}

.book-author,
.book-price {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.86rem;
}

.book-price strong {
  color: var(--color-text);
}

.amazon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  border-radius: 6px;
  background: var(--color-accent);
  color: #ffffff;
  font-weight: 800;
  margin-top: auto;
  padding: 8px 12px;
}

.amazon-button:hover,
.amazon-button:focus {
  background: var(--color-accent-dark);
  color: #ffffff;
  text-decoration: none;
}

/* 記事一覧とサイドバー */
.content-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 34px;
  align-items: start;
}

.main-column {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-panel);
  padding: 28px;
}

.article-heading {
  align-items: flex-start;
  justify-content: space-between;
}

.article-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
}

.article-tabs button {
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: #ffffff;
  color: var(--color-accent-dark);
  cursor: pointer;
  font: inherit;
  font-size: 0.9rem;
  font-weight: 800;
  line-height: 1;
  padding: 9px 14px;
}

.article-tabs button:hover,
.article-tabs button:focus,
.article-tabs button.is-active {
  background: var(--color-accent-dark);
  color: #ffffff;
}

.article-list {
  display: grid;
  gap: 22px;
}

.article-card {
  min-height: 154px;
  border: 1px solid var(--color-border-soft);
  border-radius: 8px;
  background: #ffffff;
  padding: 28px 30px;
}

.article-card h3 {
  margin: 0 0 10px;
  font-size: 1.38rem;
  line-height: 1.35;
}

.article-meta {
  margin: 0 0 6px;
  color: var(--color-muted);
  font-size: 0.84rem;
}

.article-card p {
  margin: 0;
}

.sidebar {
  display: grid;
  gap: 28px;
}

.sidebar-box {
  min-height: 168px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-panel);
  padding: 24px;
}

.sidebar-box h2 {
  margin: 0 0 12px;
  font-size: 1.18rem;
}

.sidebar-box p {
  margin: 0;
  color: var(--color-muted);
}

.about-panel {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-panel);
  padding: 28px;
}

.about-panel h2 {
  margin: 0 0 10px;
  font-size: 1.2rem;
}

.about-panel p {
  margin: 0 0 22px;
}

.about-panel p:last-child {
  margin-bottom: 0;
}

.sidebar-popular {
  min-height: 0;
  padding-bottom: 24px;
}

.sidebar-heading {
  margin-bottom: 14px;
}

.sidebar-heading h2 {
  margin: 0;
}

.popular-mini-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.sidebar-popular .cover-only-card {
  min-height: auto;
  border-color: var(--color-border);
}

.sale-calendar-box {
  min-height: 0;
}

.calendar-controls {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr) 28px;
  gap: 6px;
  margin-bottom: 10px;
}

.calendar-move {
  min-height: 34px;
  border: 0;
  background: transparent;
  color: var(--color-text);
  cursor: pointer;
  font: inherit;
  font-weight: 900;
  padding: 0;
}

.calendar-picker {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  min-width: 0;
  color: var(--color-text);
  font-weight: 800;
}

.calendar-year,
.calendar-month {
  min-height: 34px;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: #ffffff;
  color: var(--color-text);
  cursor: pointer;
  font: inherit;
  font-weight: 800;
}

.calendar-year {
  width: 74px;
}

.calendar-month {
  width: 54px;
}

.calendar-year,
.calendar-month {
  padding: 0 6px;
  text-align: center;
  text-align-last: center;
}

.calendar-move:hover,
.calendar-move:focus {
  color: var(--color-accent);
}

.calendar-year:hover,
.calendar-year:focus,
.calendar-month:hover,
.calendar-month:focus {
  border-color: var(--color-accent);
}

.calendar-move:disabled {
  color: var(--color-border);
  cursor: default;
}

.calendar-move:disabled:hover,
.calendar-move:disabled:focus {
  color: var(--color-border);
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  border-top: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  background: #ffffff;
}

.calendar-weekday,
.calendar-day {
  display: grid;
  place-items: center;
  min-height: 32px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  font-size: 0.78rem;
}

.calendar-weekday {
  color: var(--color-muted);
  font-weight: 800;
}

.calendar-day {
  background: #ffffff;
}

.calendar-day.is-today {
  box-shadow: inset 0 0 0 2px #000000;
}

.calendar-day.is-sale {
  background: #ffd58f;
  color: var(--color-text);
  font-weight: 900;
}

.calendar-day.is-empty {
  background: #fafafa;
  color: transparent;
}

.calendar-sale-list {
  display: grid;
  gap: 6px;
  margin: 12px 0 0;
  font-size: 0.84rem;
  line-height: 1.45;
}

.calendar-empty {
  color: var(--color-muted);
  margin: 0;
}

.calendar-sale-item {
  display: grid;
  grid-template-columns: 16px minmax(0, 1fr);
  gap: 6px;
  align-items: start;
}

.calendar-sale-item input {
  appearance: none;
  display: grid;
  place-items: center;
  width: 13px;
  height: 13px;
  border: 1px solid var(--color-text);
  background: #ffffff;
  margin: 3px 0 0;
}

.calendar-sale-item input:checked::before {
  content: "✓";
  color: var(--color-text);
  font-size: 0.72rem;
  font-weight: 900;
  line-height: 1;
}

.text-link {
  display: inline-block;
  font-weight: 800;
  margin-top: 10px;
}

.tab-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tab-links a {
  border: 1px solid var(--color-border-soft);
  border-radius: 6px;
  color: var(--color-text);
  font-size: 0.88rem;
  padding: 6px 10px;
}

.tab-links a:hover,
.tab-links a:focus {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

.compact-list {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 1.1em;
}

/* 一覧ページ */
.sale-card-grid,
.book-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 18px;
}

.sale-card {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: #ffffff;
  padding: 18px;
}

.sale-card h2 {
  margin: 0 0 8px;
  font-size: 1.08rem;
}

.sale-card p {
  margin: 0 0 10px;
  color: var(--color-muted);
}

.sale-period {
  display: inline-block;
  border-radius: 6px;
  background: var(--color-soft);
  color: var(--color-text);
  font-size: 0.84rem;
  font-weight: 700;
  margin-bottom: 12px;
  padding: 4px 8px;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  background: #ffffff;
  color: var(--color-muted);
  padding: 22px 0;
  text-align: center;
}

.site-footer p {
  margin: 4px 0;
}

/* スマホ表示：1カラムにして横幅を使いやすくします */
@media (max-width: 760px) {
  .container {
    width: min(100% - 24px, 1040px);
  }

  .site-header .container {
    padding: 28px 0 20px;
  }

  .nav-inner {
    justify-content: flex-start;
  }

  .content-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .section-heading {
    align-items: baseline;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 8px 12px;
  }

  .article-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .article-tabs {
    justify-content: flex-start;
  }

  .book-scroll {
    grid-auto-columns: minmax(148px, 64vw);
  }

  .cover-only-scroll {
    grid-auto-columns: minmax(104px, 38vw);
    gap: 10px;
  }

  .sale-box,
  .book-showcase,
  .main-column,
  .article-card,
  .sidebar-box {
    padding: 20px;
  }
}