/* =========================================================================
   Inkubus — site design system (Phase 1)
   文芸誌(editorial / literary press)系。クリーム紙 × 明朝見出し × インクブルー。
   アプリのライトテーマを土台に、夜/三日月/黒猫の世界観を控えめに。
   相対パス前提・file:// でも動く静的サイト。
   ========================================================================= */

/* --- design tokens ------------------------------------------------------ */
:root {
  /* palette: アプリ light テーマ踏襲 + 文芸トーン */
  --paper: #f6f3ec;        /* クリーム紙 */
  --paper-2: #efe9dc;      /* 一段沈めた紙 */
  --ink: #1c1c1c;          /* 本文 */
  --ink-deep: #14131a;     /* 見出し(やや冷たい墨) */
  --card: #ffffff;
  --card-hover: #f0ece3;
  --line: #d7d3c9;         /* 罫 */
  --line-soft: #e6e1d6;
  --accent: #3a5dc6;       /* インクブルー */
  --accent-deep: #2c47a0;
  --gold: #b8893f;         /* 装飾(三日月・約物) */
  --muted: #6b6b6b;
  --error: #c73a50;
  --success: #4d8540;

  /* type */
  --serif-jp: 'Shippori Mincho B1', 'Yu Mincho', 'YuMincho', 'Hiragino Mincho ProN', 'Noto Serif JP', serif;
  --serif-latin: 'Cormorant Garamond', 'Shippori Mincho B1', Georgia, serif;
  --sans-jp: 'Zen Kaku Gothic New', 'Hiragino Kaku Gothic ProN', 'Yu Gothic', 'Meiryo', system-ui, sans-serif;
  --mono: ui-monospace, 'SFMono-Regular', 'DM Mono', 'Menlo', monospace;

  /* layout */
  --maxw: 1120px;
  --readw: 760px;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(20, 19, 26, 0.04), 0 8px 30px rgba(20, 19, 26, 0.06);
  --shadow-lift: 0 4px 12px rgba(20, 19, 26, 0.08), 0 20px 50px rgba(20, 19, 26, 0.10);
}

/* --- reset -------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans-jp);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* ごく薄い紙のざらつき(オフラインでも効く data-uri) */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  opacity: 0.5;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.035'/%3E%3C/svg%3E");
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-deep); }

/* --- typography --------------------------------------------------------- */
h1, h2, h3, h4 {
  font-family: var(--serif-jp);
  color: var(--ink-deep);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: 0.02em;
}
.latin { font-family: var(--serif-latin); font-weight: 500; letter-spacing: 0.01em; }
.muted { color: var(--muted); }

/* --- shared chrome: header / nav --------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: saturate(1.1) blur(10px);
  border-bottom: 1px solid var(--line-soft);
}
.site-header__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0.85rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--ink-deep);
}
.brand__mark { width: 30px; height: 30px; flex-shrink: 0; border-radius: 7px; object-fit: cover; }
.brand__name {
  font-family: var(--serif-latin);
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}
.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 1.4rem;
}
.site-nav a {
  color: var(--ink);
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  padding: 0.25rem 0;
  border-bottom: 1.5px solid transparent;
  transition: border-color 0.2s, color 0.2s;
}
.site-nav a:hover { color: var(--accent); border-bottom-color: var(--accent); }
.site-nav a[aria-current='page'] { color: var(--accent); border-bottom-color: var(--accent); }
.site-nav .nav-cta {
  border: 1px solid var(--accent);
  border-radius: 999px;
  padding: 0.35rem 0.95rem;
  color: var(--accent);
  font-weight: 600;
}
.site-nav .nav-cta:hover { background: var(--accent); color: #fff; border-bottom-color: transparent; }

/* --- buttons ------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--sans-jp);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  padding: 0.7rem 1.5rem;
  border-radius: 999px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.2s, background 0.2s, color 0.2s;
}
.btn--primary { background: var(--accent); color: #fff; box-shadow: 0 6px 18px rgba(58, 93, 198, 0.25); }
.btn--primary:hover { background: var(--accent-deep); color: #fff; transform: translateY(-1px); box-shadow: 0 10px 26px rgba(58, 93, 198, 0.3); }
.btn--ghost { background: transparent; color: var(--ink-deep); border-color: var(--line); }
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-1px); }

/* --- containers --------------------------------------------------------- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem; position: relative; z-index: 1; }
.section { padding: 5.5rem 0; position: relative; z-index: 1; }
.section--tight { padding: 3.5rem 0; }
.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--gold);
  margin: 0 0 0.9rem;
}
.section__title { font-size: clamp(1.6rem, 3vw, 2.2rem); margin: 0 0 0.6rem; }
.section__lead { color: var(--muted); max-width: 56ch; margin: 0; }

/* =========================================================================
   LP (index.html)
   ========================================================================= */

/* hero */
.hero { position: relative; padding: 5.5rem 0 4rem; overflow: hidden; }
.hero__bg {
  position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background:
    radial-gradient(80% 60% at 78% 12%, rgba(58, 93, 198, 0.10), transparent 60%),
    radial-gradient(50% 50% at 12% 90%, rgba(184, 137, 63, 0.10), transparent 60%);
}
.hero__inner { position: relative; z-index: 1; display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 3rem; align-items: center; }
.hero__kicker {
  font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.26em;
  text-transform: uppercase; color: var(--gold); margin: 0 0 1.3rem;
}
.hero h1 {
  font-size: clamp(2.1rem, 4.6vw, 3.3rem);
  line-height: 1.32;
  margin: 0 0 1.4rem;
  letter-spacing: 0.02em;
  /* 日本語が「だか/ら」のように語の途中で折れないようにする。改行は <br> で明示。 */
  word-break: keep-all;
  overflow-wrap: normal;
}
.hero h1 .accent { color: var(--accent); }
.hero__sub { font-size: 1.06rem; color: #34343a; max-width: 46ch; margin: 0 0 2rem; line-height: 1.95; }
.hero__cta { display: flex; gap: 0.9rem; flex-wrap: wrap; }
.hero__meta { margin: 1.9rem 0 0; display: flex; gap: 1.4rem; flex-wrap: wrap; font-size: 0.82rem; color: var(--muted); }
.hero__meta span { display: inline-flex; align-items: center; gap: 0.4rem; }
.hero__meta .dot { width: 5px; height: 5px; border-radius: 50%; background: var(--gold); }

/* hero visual: 三日月 + 積まれた本 + 黒猫 */
.hero__art { position: relative; aspect-ratio: 4 / 5; display: flex; align-items: center; justify-content: center; }
/* 中央に金×青のやわらかいグロー */
.hero__art::before {
  content: ''; position: absolute; width: 76%; aspect-ratio: 1; border-radius: 50%;
  background: radial-gradient(circle at 50% 45%, rgba(58,93,198,0.18), rgba(184,137,63,0.10) 45%, transparent 70%);
  filter: blur(6px); z-index: 0;
}
/* 星空(About 移植): accent 基調 + マスクで周辺フェード */
.hero__stars {
  position: absolute; inset: 0; width: 100%; height: 100%; z-index: 0;
  color: var(--accent); opacity: 0.55;
  -webkit-mask-image: radial-gradient(ellipse 62% 58% at center, #000 38%, transparent 86%);
  mask-image: radial-gradient(ellipse 62% 58% at center, #000 38%, transparent 86%);
}
/* 猫アイコンのエンブレム(アプリのアイコンそのまま) */
.hero__emblem {
  position: relative; z-index: 1;
  width: clamp(168px, 24vw, 252px); height: auto;
  border-radius: clamp(26px, 4vw, 44px);
  box-shadow: 0 20px 54px rgba(20, 19, 26, 0.20), 0 6px 16px rgba(20, 19, 26, 0.10);
}

/* staggered load */
.reveal { opacity: 0; transform: translateY(14px); animation: rise 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards; }
.reveal.d1 { animation-delay: 0.05s; }
.reveal.d2 { animation-delay: 0.15s; }
.reveal.d3 { animation-delay: 0.25s; }
.reveal.d4 { animation-delay: 0.35s; }
.reveal.d5 { animation-delay: 0.45s; }
@keyframes rise { to { opacity: 1; transform: none; } }
@media (prefers-reduced-motion: reduce) { .reveal { animation: none; opacity: 1; transform: none; } }

/* ornamental rule */
.rule-orn { display: flex; align-items: center; gap: 1rem; color: var(--gold); margin: 0 auto; max-width: 200px; }
.rule-orn::before, .rule-orn::after { content: ''; height: 1px; flex: 1; background: linear-gradient(to var(--d, right), transparent, var(--line)); }
.rule-orn::before { --d: left; }

/* features */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; margin-top: 2.5rem; }
.feature-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem 1.5rem;
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}
.feature-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lift); border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); }
.feature-card__icon { width: 38px; height: 38px; color: var(--accent); margin-bottom: 1rem; }
.feature-card h3 { font-size: 1.16rem; margin: 0 0 0.5rem; }
.feature-card p { margin: 0; font-size: 0.92rem; color: #44444a; line-height: 1.8; }
.feature-card .tag-new {
  display: inline-block; font-family: var(--mono); font-size: 0.62rem; letter-spacing: 0.12em;
  color: var(--gold); border: 1px solid color-mix(in srgb, var(--gold) 50%, transparent);
  border-radius: 999px; padding: 0.05rem 0.5rem; margin-left: 0.5rem; vertical-align: middle;
}

/* steps */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; margin-top: 2.5rem; counter-reset: step; }
.step { position: relative; padding-top: 2.6rem; }
.step::before {
  counter-increment: step; content: counter(step, decimal-leading-zero);
  position: absolute; top: 0; left: 0;
  font-family: var(--serif-latin); font-size: 2.2rem; font-weight: 600;
  color: color-mix(in srgb, var(--accent) 30%, var(--paper)); line-height: 1;
}
.step h3 { font-size: 1.16rem; margin: 0 0 0.4rem; }
.step p { margin: 0; color: #44444a; font-size: 0.92rem; }

/* screenshots */
.shots { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; margin-top: 2.5rem; }
.shot {
  aspect-ratio: 16 / 10;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background:
    repeating-linear-gradient(45deg, var(--paper-2), var(--paper-2) 12px, var(--card) 12px, var(--card) 24px);
  display: flex; align-items: center; justify-content: center;
  color: var(--muted); font-size: 0.85rem; box-shadow: var(--shadow);
}
.shot { position: relative; }
.shot__img { width: 100%; height: 100%; object-fit: cover; display: block; }
/* クリックで拡大できる affordance */
.shot--zoom { cursor: zoom-in; }
.shot--zoom .shot__img { transition: transform 0.35s ease, filter 0.35s ease; }
.shot--zoom:hover .shot__img, .shot--zoom:focus-visible .shot__img { transform: scale(1.04); filter: brightness(0.95); }
.shot--zoom:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.shot__zoom {
  position: absolute; right: 0.6rem; bottom: 0.6rem;
  width: 34px; height: 34px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: rgba(20, 19, 26, 0.55); color: #fff;
  -webkit-backdrop-filter: blur(2px); backdrop-filter: blur(2px);
  transition: background 0.2s ease, transform 0.2s ease;
}
.shot--zoom:hover .shot__zoom, .shot--zoom:focus-visible .shot__zoom { background: var(--accent); transform: scale(1.08); }
.shot__zoom svg { width: 18px; height: 18px; }

/* ライトボックス(スクショ拡大) */
.lightbox { position: fixed; inset: 0; z-index: 1000; display: flex; align-items: center; justify-content: center; padding: 4vmin; background: rgba(18, 17, 22, 0.86); cursor: zoom-out; }
.lightbox[hidden] { display: none; }
.lightbox__img { max-width: 100%; max-height: 100%; border-radius: 8px; box-shadow: 0 24px 70px rgba(0, 0, 0, 0.55); cursor: default; }
.lightbox__close { position: absolute; top: 1rem; right: 1.2rem; width: 46px; height: 46px; border: none; border-radius: 50%; background: rgba(255, 255, 255, 0.14); color: #fff; font-size: 1.7rem; line-height: 1; cursor: pointer; transition: background 0.2s ease; }
.lightbox__close:hover { background: rgba(255, 255, 255, 0.28); }

/* CTA band */
.cta-band { background: var(--ink-deep); color: #f0eee9; border-radius: 16px; padding: 3.2rem; text-align: center; position: relative; overflow: hidden; }
.cta-band::after {
  content: ''; position: absolute; inset: 0; opacity: 0.5; pointer-events: none;
  background: radial-gradient(60% 80% at 80% 10%, rgba(184, 137, 63, 0.18), transparent 60%),
              radial-gradient(50% 60% at 10% 100%, rgba(58, 93, 198, 0.22), transparent 60%);
}
.cta-band > * { position: relative; z-index: 1; }
.cta-band h2 { color: #fbf8f1; font-size: clamp(1.5rem, 3vw, 2.1rem); margin: 0 0 0.8rem; }
.cta-band p { color: #c9c6c0; margin: 0 auto 1.8rem; max-width: 48ch; }
.cta-band .btn--ghost { color: #f0eee9; border-color: rgba(255,255,255,0.3); }
.cta-band .btn--ghost:hover { color: #fff; border-color: #fff; }

/* footer */
.site-footer { border-top: 1px solid var(--line-soft); padding: 3rem 0 4rem; margin-top: 2rem; }
.site-footer__inner { max-width: var(--maxw); margin: 0 auto; padding: 0 1.5rem; display: flex; flex-wrap: wrap; gap: 2rem; justify-content: space-between; align-items: flex-start; }
.site-footer__brand { max-width: 32ch; }
.site-footer__brand p { color: var(--muted); font-size: 0.84rem; margin: 0.6rem 0 0; }
.site-footer__cols { display: flex; gap: 3rem; flex-wrap: wrap; }
.foot-col h4 { font-family: var(--sans-jp); font-size: 0.72rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--muted); margin: 0 0 0.8rem; }
.foot-col a { display: block; color: var(--ink); font-size: 0.88rem; padding: 0.2rem 0; }
.foot-col a:hover { color: var(--accent); }
.site-footer__legal { width: 100%; border-top: 1px solid var(--line-soft); margin-top: 2rem; padding-top: 1.4rem; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.6rem; color: var(--muted); font-size: 0.76rem; }

/* =========================================================================
   Doc page (help/*.html)
   ========================================================================= */
.doc { display: grid; grid-template-columns: 230px minmax(0, 1fr); gap: 3.5rem; max-width: var(--maxw); margin: 0 auto; padding: 2.8rem 1.5rem 5rem; position: relative; z-index: 1; }
.doc__toc { position: sticky; top: 5.2rem; align-self: start; max-height: calc(100vh - 7rem); overflow-y: auto; }
.doc__toc h4 { font-family: var(--mono); font-size: 0.68rem; letter-spacing: 0.2em; text-transform: uppercase; color: var(--gold); margin: 0 0 0.9rem; }
.doc__toc ol { list-style: none; margin: 0; padding: 0; border-left: 1px solid var(--line); }
.doc__toc li { margin: 0; }
.doc__toc a { display: block; color: var(--muted); font-size: 0.85rem; line-height: 1.5; padding: 0.32rem 0 0.32rem 0.9rem; margin-left: -1px; border-left: 1.5px solid transparent; transition: color 0.15s, border-color 0.15s; }
.doc__toc a:hover { color: var(--ink); }
.doc__toc a[aria-current='true'] { color: var(--accent); border-left-color: var(--accent); }

.doc__main { max-width: var(--readw); min-width: 0; }
.doc__breadcrumb { font-size: 0.8rem; color: var(--muted); margin: 0 0 1rem; }
.doc__breadcrumb a { color: var(--muted); }
.doc__breadcrumb a:hover { color: var(--accent); }
.doc__title { font-size: clamp(1.9rem, 4vw, 2.5rem); margin: 0 0 0.5rem; }
.doc__intro { color: #44444a; font-size: 1.05rem; line-height: 1.95; margin: 0 0 2.5rem; }

.doc__main h2 {
  font-size: 1.5rem; margin: 3rem 0 1rem; padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--line-soft); scroll-margin-top: 5.5rem;
  display: flex; align-items: baseline; gap: 0.7rem;
}
.doc__main h2 .num { font-family: var(--serif-latin); color: var(--gold); font-size: 1.9rem; font-weight: 600; line-height: 1; letter-spacing: 0.01em; }
.doc__main h3 { font-size: 1.16rem; margin: 2rem 0 0.7rem; scroll-margin-top: 5.5rem; }
.doc__main p { margin: 0 0 1.1rem; }
.doc__main ul, .doc__main ol { margin: 0 0 1.3rem; padding-left: 1.3rem; }
.doc__main li { margin: 0.4rem 0; }
.doc__main li::marker { color: var(--accent); }
.doc__main strong { color: var(--ink-deep); font-weight: 600; }
.doc__main a { border-bottom: 1px solid color-mix(in srgb, var(--accent) 35%, transparent); }
.doc__main a:hover { border-bottom-color: var(--accent); }

/* 画面名チップ / inline code */
.screen { font-family: var(--sans-jp); font-size: 0.86em; background: color-mix(in srgb, var(--accent) 9%, var(--card)); color: var(--accent-deep); border: 1px solid color-mix(in srgb, var(--accent) 22%, transparent); border-radius: 5px; padding: 0.05em 0.45em; white-space: nowrap; }
/* 別エンドのエンド名バッジ(アプリと同じアンバー) */
.ending-badge { display: inline-block; font-size: 0.72em; font-weight: 500; color: var(--gold); background: color-mix(in srgb, var(--gold) 12%, transparent); border: 1px solid color-mix(in srgb, var(--gold) 45%, transparent); border-radius: 999px; padding: 0.02em 0.5em; margin: 0 0.1em; white-space: nowrap; vertical-align: middle; }
code { font-family: var(--mono); font-size: 0.86em; background: var(--paper-2); border: 1px solid var(--line-soft); border-radius: 5px; padding: 0.08em 0.4em; }

/* code block(複数行コマンド)— 暗色ブロックでクリーム地に映える */
.doc__main pre {
  background: var(--ink-deep);
  color: #e8e4da;
  font-family: var(--mono);
  font-size: 0.83rem;
  line-height: 1.75;
  padding: 1rem 1.2rem;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 1.2rem 0 1.4rem;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}
.doc__main pre code { background: none; border: none; padding: 0; color: inherit; font-size: inherit; }
.doc__main pre .c { color: #9aa6c4; }  /* コメント行 */

/* table */
.doc__main table { width: 100%; border-collapse: collapse; margin: 1.3rem 0 1.5rem; font-size: 0.92rem; }
.doc__main th, .doc__main td { text-align: left; padding: 0.55rem 0.85rem; border-bottom: 1px solid var(--line-soft); }
.doc__main th { font-family: var(--sans-jp); font-weight: 600; color: var(--ink-deep); border-bottom: 1px solid var(--line); background: var(--paper-2); }
.doc__main td.ok { color: var(--success); font-weight: 600; }
.doc__main td.no { color: var(--muted); }

/* callout */
.callout { display: flex; gap: 0.9rem; border-radius: var(--radius); padding: 1rem 1.2rem; margin: 1.4rem 0; font-size: 0.92rem; line-height: 1.8; border: 1px solid; }
.callout__icon { flex-shrink: 0; width: 20px; height: 20px; margin-top: 0.2rem; }
.callout p { margin: 0; }
.callout--tip { background: color-mix(in srgb, var(--accent) 6%, var(--card)); border-color: color-mix(in srgb, var(--accent) 25%, transparent); }
.callout--tip .callout__icon { color: var(--accent); }
.callout--warn { background: color-mix(in srgb, var(--gold) 10%, var(--card)); border-color: color-mix(in srgb, var(--gold) 40%, transparent); }
.callout--warn .callout__icon { color: var(--gold); }

/* step list (numbered, boxed) */
.steplist { list-style: none; counter-reset: s; padding: 0; margin: 1.3rem 0; }
.steplist li { counter-increment: s; position: relative; padding: 0 0 1.1rem 2.6rem; margin: 0; }
.steplist li::before { content: counter(s); position: absolute; left: 0; top: -0.1rem; width: 1.7rem; height: 1.7rem; border-radius: 50%; background: var(--accent); color: #fff; font-family: var(--serif-latin); font-size: 0.9rem; display: flex; align-items: center; justify-content: center; }

/* FAQ アコーディオン */
.faq-cat { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--gold); margin: 2.4rem 0 0.9rem; }
.faq-cat:first-of-type { margin-top: 1rem; }
.faq-item { border: 1px solid var(--line); border-radius: var(--radius); margin: 0.55rem 0; background: var(--card); }
.faq-item > summary { cursor: pointer; padding: 0.9rem 1.2rem; font-weight: 600; color: var(--ink-deep); list-style: none; display: flex; justify-content: space-between; gap: 1rem; align-items: center; }
.faq-item > summary::-webkit-details-marker { display: none; }
.faq-item > summary::after { content: '＋'; color: var(--accent); font-size: 1.05rem; flex-shrink: 0; }
.faq-item[open] > summary::after { content: '−'; }
.faq-item > summary:hover { color: var(--accent); }
.faq-item__body { padding: 0 1.2rem 1.05rem; }
.faq-item__body > *:first-child { margin-top: 0; }
.faq-item__body p { margin: 0 0 0.8rem; }

/* changelog */
.cl-entry { margin: 0 0 2.6rem; }
.cl-ver { display: flex; align-items: baseline; gap: 0.8rem; flex-wrap: wrap; margin: 0 0 0.4rem; padding-bottom: 0.5rem; border-bottom: 1px solid var(--line-soft); }
.cl-ver h2 { font-size: 1.5rem; margin: 0; border: none; padding: 0; }
.cl-ver .cl-tag { font-family: var(--mono); font-size: 0.68rem; letter-spacing: 0.12em; color: var(--accent); border: 1px solid color-mix(in srgb, var(--accent) 40%, transparent); border-radius: 999px; padding: 0.08em 0.6em; }
.cl-ver .cl-date { color: var(--muted); font-size: 0.85rem; font-family: var(--mono); }
.cl-entry h3 { font-size: 1.02rem; color: var(--gold); margin: 1.3rem 0 0.5rem; font-family: var(--sans-jp); letter-spacing: 0.04em; }

/* doc footer prev/next */
.doc__pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3.5rem; padding-top: 1.6rem; border-top: 1px solid var(--line-soft); flex-wrap: wrap; }
.doc__pager a { display: inline-flex; flex-direction: column; gap: 0.2rem; padding: 0.8rem 1.2rem; border: 1px solid var(--line); border-radius: var(--radius); min-width: 200px; }
.doc__pager a:hover { border-color: var(--accent); }
.doc__pager .lbl { font-size: 0.72rem; color: var(--muted); letter-spacing: 0.1em; }
.doc__pager .ttl { color: var(--ink-deep); font-weight: 600; font-size: 0.95rem; }

/* doc サイドバー: ガイド一覧(全ページ横断) + ページ内目次 */
.doc__guides { margin: 0 0 0.4rem; }
.doc__guides-top {
  display: block; font-size: 0.82rem; font-weight: 600; color: var(--accent);
  padding: 0 0 0.2rem; margin: 0 0 0.5rem;
}
.doc__guides-top::before { content: '‹ '; }
.doc__guides-grp {
  font-family: var(--mono); font-size: 0.62rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--gold); margin: 0.95rem 0 0.25rem;
}
.doc__guides a:not(.doc__guides-top) {
  display: block; color: var(--muted); font-size: 0.83rem; line-height: 1.45;
  padding: 0.24rem 0 0.24rem 0.8rem; border-left: 1.5px solid var(--line-soft);
  transition: color 0.15s, border-color 0.15s;
}
.doc__guides a:not(.doc__guides-top):hover { color: var(--ink); border-left-color: var(--line); }
.doc__guides a.is-here { color: var(--accent); border-left-color: var(--accent); font-weight: 600; }
.doc__onthispage { margin-top: 1.3rem; padding-top: 1.1rem; border-top: 1px solid var(--line-soft); }

/* ガイド ディレクトリ(使い方トップ + LP のガイド section で共用) */
.guide-groups { display: grid; gap: 2.2rem; margin-top: 2.2rem; }
.guide-group__h { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.2em; text-transform: uppercase; color: var(--gold); margin: 0 0 1rem; }
.guide-cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
.guide-card {
  display: block; padding: 1.05rem 1.2rem; background: var(--card);
  border: 1px solid var(--line); border-radius: var(--radius);
  transition: transform 0.18s, box-shadow 0.18s, border-color 0.18s;
}
.guide-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-lift); border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); }
.guide-card__t { font-family: var(--serif-jp); font-weight: 600; font-size: 1.02rem; color: var(--ink-deep); margin: 0 0 0.3rem; display: flex; align-items: center; gap: 0.5rem; flex-wrap: wrap; }
.guide-card__d { margin: 0; font-size: 0.86rem; color: #55555c; line-height: 1.7; }
.guide-card .gc-new { font-family: var(--mono); font-size: 0.6rem; letter-spacing: 0.1em; color: var(--accent); border: 1px solid color-mix(in srgb, var(--accent) 40%, transparent); border-radius: 999px; padding: 0.05em 0.5em; line-height: 1.6; }

/* 実演動画(YouTube facade: サムネ → クリックで iframe ロード) */
.videos { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.6rem; margin-top: 2.2rem; }
.video { margin: 0; }
.video__frame { position: relative; aspect-ratio: 16 / 9; border-radius: var(--radius); overflow: hidden; cursor: pointer; background: #14131a; border: 1px solid var(--line); box-shadow: var(--shadow); }
.video__thumb { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform 0.35s ease, filter 0.35s ease; }
.video__frame:hover .video__thumb, .video__frame:focus-visible .video__thumb { transform: scale(1.03); filter: brightness(0.9); }
.video__play { position: absolute; inset: 0; margin: auto; width: 66px; height: 66px; pointer-events: none; }
.video__play svg { width: 100%; height: 100%; filter: drop-shadow(0 3px 10px rgba(20, 19, 26, 0.4)); transition: transform 0.2s ease; }
.video__play circle { fill: var(--accent); opacity: 0.92; }
.video__frame:hover .video__play svg, .video__frame:focus-visible .video__play svg { transform: scale(1.08); }
.video__frame:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.video__frame iframe { width: 100%; height: 100%; border: 0; display: block; }
.video__cap { margin: 0.7rem 0 0; font-size: 0.88rem; color: #55555c; line-height: 1.7; }

/* =========================================================================
   responsive
   ========================================================================= */
@media (max-width: 880px) {
  .hero__inner { grid-template-columns: 1fr; gap: 2rem; }
  .hero__art { max-width: 340px; margin: 0 auto; }
  .feature-grid, .steps, .shots { grid-template-columns: 1fr 1fr; }
  .doc { grid-template-columns: 1fr; gap: 1.5rem; }
  .doc__toc { position: static; max-height: none; border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.2rem; background: var(--card); }
  .doc__toc ol { border-left: none; }
}
@media (max-width: 560px) {
  .section { padding: 3.5rem 0; }
  .site-nav { gap: 0.9rem; }
  .site-nav a.nav-guide, .site-nav a.nav-cta { display: inline; }   /* スマホは「使い方」+ 購入CTA を残す */
  .site-nav a:not(.nav-cta):not(.nav-guide) { display: none; }
  .feature-grid, .steps, .shots, .guide-cards, .videos { grid-template-columns: 1fr; }
  .cta-band { padding: 2.2rem 1.4rem; }
  .hero__cta { flex-direction: column; align-items: stretch; }
  .hero__cta .btn { justify-content: center; }
}