/* ==========================================================================
   WHYBUY Legal — Light Editorial
   見出し: Schibsted Grotesk (欧文) + Zen Kaku Gothic New (和文)
   配色:   アプリ本体の Warm Neutral + 紺碧 (#0689B1)
   ========================================================================== */

:root {
  --bg: #FAF9F7;
  --bg-tint: #F3F1ED;
  --surface: #FFFFFF;
  --ink: #1C1917;
  --ink-soft: #57534E;
  --ink-mute: #857F7A;
  --heading: #1C1917;
  --accent: #0689B1;
  --accent-deep: #056A8B;
  --accent-tint: #E6F3F8;
  --line: #E7E5E4;
  --line-soft: #F1EFED;
  --line-strong: #D6D3D1;
  --header: #16233F;

  --shadow-sm: 0 1px 2px rgba(28, 25, 23, .05), 0 1px 1px rgba(28, 25, 23, .03);
  --shadow-md: 0 6px 22px -6px rgba(28, 25, 23, .10), 0 2px 8px -3px rgba(28, 25, 23, .06);
  --shadow-lg: 0 22px 56px -16px rgba(28, 25, 23, .18);

  --radius: 16px;
  --radius-sm: 10px;
  --maxw: 1180px;
  --readw: 720px;

  --font-display: "Schibsted Grotesk", "Zen Kaku Gothic New", -apple-system, sans-serif;
  --font-body: "Zen Kaku Gothic New", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
}

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

html {
  -webkit-text-size-adjust: 100%;
  font-size: 17px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.75;
  font-feature-settings: "palt" 1;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-wrap: break-word;
  word-break: normal;
  line-break: strict;
}

::selection { background: rgba(6, 137, 177, .16); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* --- reading progress ---------------------------------------------------- */
.reading-progress {
  position: fixed;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), #38BDF8);
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 60;
  will-change: transform;
}

/* --- site header --------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(22, 35, 63, .92);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}

.site-header__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: .7em 1.5em;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1em;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: .55em;
  text-decoration: none;
  color: #fff;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.02rem;
  letter-spacing: .09em;
}

.brand__logo { height: 26px; width: 26px; display: block; }

/* nav */
.nav { display: flex; align-items: center; gap: 1em; flex-wrap: wrap; }

.nav__group--docs {
  display: flex;
  background: rgba(255, 255, 255, .08);
  border-radius: 999px;
  padding: 3px;
  gap: 2px;
}

.nav__tab {
  padding: .42em .95em;
  border-radius: 999px;
  text-decoration: none;
  color: rgba(255, 255, 255, .62);
  font-size: .85rem;
  font-weight: 500;
  transition: color .2s, background .2s;
  white-space: nowrap;
}
.nav__tab.is-active { background: rgba(255, 255, 255, .95); color: var(--heading); }
.nav__tab:hover:not(.is-active) { color: #fff; }

.nav__back { color: rgba(255, 255, 255, .72); text-decoration: none; font-size: .88rem; transition: color .2s; }
.nav__back:hover { color: #5FCDEA; }

/* --- layout -------------------------------------------------------------- */
.layout {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(2em, 5vw, 4em) 1.5em 2em;
}

@media (min-width: 1080px) {
  .layout {
    display: grid;
    grid-template-columns: 248px minmax(0, 1fr);
    gap: clamp(2.5em, 5vw, 5em);
  }
}

.doc-main { min-width: 0; }
.doc-article { max-width: var(--readw); }

/* --- table of contents --------------------------------------------------- */
.toc { display: none; }

@media (min-width: 1080px) {
  .toc {
    display: block;
    position: sticky;
    top: 92px;
    align-self: start;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    overscroll-behavior: contain;
    padding: 0 .5em 1em 0;
  }
  .toc.is-empty { display: none; }
}

.toc__title {
  font-size: .7rem;
  letter-spacing: .15em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin: 0 0 1.1em;
  font-weight: 600;
}

.toc__nav { display: flex; flex-direction: column; border-left: 1px solid var(--line); }

.toc__link {
  display: flex;
  gap: .7em;
  align-items: baseline;
  padding: .5em .9em;
  margin-left: -1px;
  border-left: 2px solid transparent;
  text-decoration: none;
  color: var(--ink-soft);
  font-size: .85rem;
  line-height: 1.45;
  transition: color .2s, border-color .2s;
}
.toc__link:hover { color: var(--heading); }
.toc__link.is-current { color: var(--accent); border-left-color: var(--accent); font-weight: 500; }

.toc__num {
  font-family: var(--font-display);
  font-size: .72rem;
  color: var(--ink-mute);
  font-weight: 600;
  min-width: 2.2em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.toc--wide .toc__num { min-width: 3.4em; }
.toc__text { min-width: 0; }
.toc__link.is-current .toc__num { color: var(--accent); }

/* --- document head ------------------------------------------------------- */
.doc-head { margin-bottom: 2.6em; }

.doc-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .55em;
  font-size: .76rem;
  letter-spacing: .17em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
  margin: 0 0 1.3em;
}
.doc-eyebrow__dot {
  width: 7px; height: 7px;
  background: var(--accent);
  transform: rotate(45deg);
  border-radius: 1px;
}

.doc-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(2.1rem, 1.55rem + 2.4vw, 3rem);
  line-height: 1.13;
  letter-spacing: -.01em;
  color: var(--heading);
  margin: 0 0 .35em;
}

.doc-subtitle {
  font-size: 1.12rem;
  color: var(--ink-soft);
  line-height: 1.65;
  margin: 0 0 1.6em;
  max-width: 36em;
  font-weight: 400;
}

.doc-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4em 2.6em;
  padding-top: 1.4em;
  border-top: 1px solid var(--line);
}
.doc-meta__item { display: flex; flex-direction: column; gap: .3em; }
.doc-meta__label {
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.doc-meta__value {
  font-size: .95rem;
  color: var(--heading);
  font-weight: 500;
  font-family: var(--font-display);
  font-variant-numeric: tabular-nums;
}
.doc-meta__link { color: var(--accent); text-decoration: none; }
.doc-meta__link:hover { text-decoration: underline; }

/* --- document body ------------------------------------------------------- */
.doc-body > :first-child { margin-top: 0; }

.doc-body h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.4rem, 1.15rem + 1vw, 1.75rem);
  line-height: 1.3;
  color: var(--heading);
  margin: 3em 0 .9em;
  padding-top: 1.8em;
  border-top: 1px solid var(--line);
  scroll-margin-top: 92px;
}
.doc-body h2:first-of-type { padding-top: 0; border-top: none; margin-top: 1.2em; }

/* 見出し自身が持つ番号 (第1条 / 1.) を小さなラベルとして上に出す (JSが付与) */
.doc-body h2 .h-num {
  display: block;
  font-family: var(--font-display);
  font-size: .82rem;
  font-weight: 600;
  letter-spacing: .18em;
  color: var(--accent);
  margin-bottom: .5em;
}

.doc-body h3 {
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 1.08rem;
  color: var(--heading);
  margin: 2.1em 0 .6em;
  scroll-margin-top: 92px;
}

.doc-body p {
  margin: 1em 0;
  color: var(--ink);
  line-height: 1.95;
}

.doc-body a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color .2s, text-decoration-thickness .2s;
}
.doc-body a:hover { color: var(--accent-deep); text-decoration-thickness: 2px; }

.doc-body strong { font-weight: 700; color: var(--heading); }

/* lists */
.doc-body ul { list-style: none; padding-left: .2em; margin: 1.1em 0; }
.doc-body ul li {
  position: relative;
  padding-left: 1.6em;
  margin: .55em 0;
  line-height: 1.85;
}
.doc-body ul li::before {
  content: "";
  position: absolute;
  left: .25em;
  top: .72em;
  width: 6px; height: 6px;
  background: var(--accent);
  border-radius: 1px;
  transform: rotate(45deg);
}
.doc-body ol { padding-left: 1.4em; margin: 1.1em 0; }
.doc-body ol li { margin: .55em 0; line-height: 1.85; padding-left: .3em; }
.doc-body li > ul, .doc-body li > ol { margin: .4em 0; }

/* callout (blockquote) */
.doc-body blockquote {
  margin: 1.7em 0;
  padding: 1.1em 1.4em 1.1em 1.5em;
  background: var(--accent-tint);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  color: #1D2A2F;
  font-size: .96rem;
}
.doc-body blockquote p { margin: .35em 0; line-height: 1.8; }
.doc-body blockquote p:first-child { margin-top: 0; }
.doc-body blockquote p:last-child { margin-bottom: 0; }
.doc-body blockquote strong { color: var(--accent-deep); }
.doc-body blockquote a { color: var(--accent-deep); }

/* tables */
.table-wrap {
  margin: 1.7em 0;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  -webkit-overflow-scrolling: touch;
}
.doc-body table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-size: .94rem;
  line-height: 1.65;
}
.doc-body :where(table) :where(th, td) {
  padding: .8em 1.1em;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line-soft);
}
.doc-body thead th {
  background: var(--bg-tint);
  color: var(--heading);
  font-weight: 700;
  font-size: .8rem;
  letter-spacing: .03em;
  white-space: nowrap;
}
.doc-body tbody tr:last-child td { border-bottom: none; }
.doc-body tbody tr { transition: background .15s; }
.doc-body tbody tr:hover { background: rgba(6, 137, 177, .035); }
.doc-body td:first-child { color: var(--heading); font-weight: 500; white-space: nowrap; }

/* hr */
.doc-body hr {
  border: none;
  height: 1px;
  background: var(--line);
  margin: 2.6em 0;
}
.doc-body h1 { display: none; } /* md先頭のH1はレイアウト側で描画するため隠す */

/* code (稀) */
.doc-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .88em;
  background: var(--bg-tint);
  padding: .12em .4em;
  border-radius: 5px;
}

/* --- footer -------------------------------------------------------------- */
.site-footer {
  max-width: var(--readw);
  margin: 4em 0 0;
  padding: 2.6em 0 1em;
  border-top: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 1.1em;
}
.site-footer__brand {
  display: flex;
  align-items: center;
  gap: .5em;
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--heading);
  font-size: .95rem;
  letter-spacing: .06em;
}
.site-footer__logo { height: 18px; width: 18px; display: block; }
.site-footer__links { display: flex; flex-wrap: wrap; gap: 1.3em; }
.site-footer__links a { color: var(--ink-soft); text-decoration: none; font-size: .88rem; transition: color .2s; }
.site-footer__links a:hover { color: var(--accent); }
.site-footer__legal { font-size: .8rem; color: var(--ink-mute); margin: 0; }

/* --- page layout (目次なしの素のページ) ------------------------------------ */
.layout--narrow { display: block; }
.layout--narrow .doc-article { margin: 0 auto; }

/* --- home / landing ------------------------------------------------------ */
.home {
  max-width: 940px;
  margin: 0 auto;
  padding: clamp(3em, 9vw, 6.5em) 1.5em 3em;
}

.hero { text-align: center; margin-bottom: clamp(2.5em, 6vw, 4.2em); }
.hero__logo {
  height: 68px;
  width: 68px;
  display: inline-block;
  margin: 0 auto 1.6em;
}
.hero__eyebrow {
  font-size: .8rem;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
  margin: 0 0 1.3em;
}
.hero__title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.8rem, 1.35rem + 2vw, 2.5rem);
  line-height: 1.2;
  letter-spacing: -.015em;
  color: var(--heading);
  margin: 0 0 .55em;
}
.hero__lead { font-size: 1.1rem; color: var(--ink-soft); line-height: 1.75; margin: 0; }
.hero__lead-sub { color: var(--ink-mute); font-size: .92rem; letter-spacing: .01em; }

.doc-cards { display: grid; gap: 1.4em; grid-template-columns: 1fr; }
@media (min-width: 680px) { .doc-cards { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1000px) { .doc-cards { grid-template-columns: repeat(3, 1fr); } }

.doc-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 2.1em 1.9em;
  box-shadow: var(--shadow-sm);
  transition: transform .25s, box-shadow .25s, border-color .25s;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-decoration: none;
  color: inherit;
}
.doc-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); border-color: rgba(6, 137, 177, .3); }
.doc-card__icon {
  width: 48px; height: 48px;
  display: grid;
  place-items: center;
  border-radius: 13px;
  background: var(--accent-tint);
  color: var(--accent);
  margin-bottom: 1.3em;
}
.doc-card__icon svg { width: 25px; height: 25px; }
.doc-card__title { font-family: var(--font-display); font-weight: 600; font-size: 1.18rem; line-height: 1.45; color: var(--heading); margin: 0 0 .2em; }
.doc-card__title-en {
  font-size: .8rem;
  letter-spacing: .08em;
  color: var(--accent);
  text-transform: uppercase;
  font-weight: 600;
  margin: 0 0 1.1em;
}
.doc-card__desc { font-size: .92rem; color: var(--ink-soft); line-height: 1.65; margin: 0 0 1.7em; }
.doc-card__more {
  margin-top: auto;
  display: inline-flex;
  align-items: center;
  gap: .45em;
  font-size: .88rem;
  font-weight: 600;
  color: var(--accent);
}
.doc-card__more::after { content: "→"; transition: transform .2s; }
.doc-card:hover .doc-card__more::after { transform: translateX(3px); }

.home-note {
  text-align: center;
  margin: 2.8em auto 0;
  max-width: 44em;
  font-size: .88rem;
  color: var(--ink-mute);
  line-height: 1.8;
}
.home-note a { color: var(--accent); text-decoration: none; }
.home-note a:hover { text-decoration: underline; }

.site-footer--home {
  max-width: none;
  text-align: center;
  border-top: 1px solid var(--line);
  margin: 0;
  padding: 2.2em 1.5em;
  align-items: center;
}

/* --- motion -------------------------------------------------------------- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: none; }
}

.doc-eyebrow, .doc-title, .doc-subtitle, .doc-meta { animation: fadeUp .65s cubic-bezier(.16, .84, .44, 1) both; }
.doc-title { animation-delay: .05s; }
.doc-subtitle { animation-delay: .11s; }
.doc-meta { animation-delay: .17s; }

.hero__logo { animation: fadeUp .6s cubic-bezier(.16, .84, .44, 1) both; }
.hero__title { animation: fadeUp .7s cubic-bezier(.16, .84, .44, 1) .07s both; }
.hero__lead { animation: fadeUp .7s cubic-bezier(.16, .84, .44, 1) .15s both; }
.doc-card { animation: fadeUp .7s cubic-bezier(.16, .84, .44, 1) both; }
.doc-card:nth-child(2) { animation-delay: .08s; }
.doc-card:nth-child(3) { animation-delay: .16s; }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}

/* --- print --------------------------------------------------------------- */
@media print {
  .site-header, .toc, .reading-progress, .site-footer__links { display: none !important; }
  body { background: #fff; }
  .layout { display: block; max-width: none; padding: 0; }
  .doc-article, .site-footer { max-width: none; }
  .doc-body a { color: var(--ink); text-decoration: none; }
  .table-wrap { box-shadow: none; }
  .doc-body h2 { break-after: avoid; }
}