/* ==========================================================================
   AiYin Technology 公式サイト v2 共通スタイル
   設計：ソラ（Fable 5）／実装：リク（Opus 4.7）
   方針：ありきたりAIサイトの排除（設計書§2）
   - 12カラム非対称グリッド／格差レイアウト
   - ドットグリッド背景／巨大ゴースト文字／縦書きアクセント
   - フォント表情（Noto Serif JP＋Montserrat 200極細大サイズ）
   - IntersectionObserverによるフェード＋stagger
   ========================================================================== */

/* ==========================================================================
   1. Reset
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
img, picture, svg, video { display: block; max-width: 100%; height: auto; }
button { font: inherit; cursor: pointer; background: none; border: none; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
input, textarea, select { font: inherit; }

/* ==========================================================================
   2. Design Tokens（設計書§2-2 準拠）
   ========================================================================== */
:root {
  /* Brand color（アクセント専用・面で使うのはCTA帯1箇所だけ） */
  --aiyin-orange: #DF5D21;
  --aiyin-orange-dark: #B84A15;
  --aiyin-orange-soft: rgba(223, 93, 33, 0.08);

  /* 重心色（フッター・スタッツ帯） */
  --aiyin-navy: #12395C;
  --aiyin-navy-dark: #0B2740;

  /* Ink / Neutrals（暖色寄り・青系にしない） */
  --ink: #1A202C;
  --ink-sub: #5B6472;
  --paper: #FFFFFF;
  --paper-soft: #F7F6F4;
  --paper-warm: #FBF8F4;
  --line: #E8E6E2;

  /* Layout */
  --wrap: 1180px;
  --wrap-narrow: 920px;
  --gutter: clamp(16px, 4vw, 32px);

  /* Type */
  --font-jp: "Noto Sans JP", "Yu Gothic UI", "Yu Gothic", "Hiragino Kaku Gothic ProN", "Meiryo", system-ui, sans-serif;
  --font-serif: "Noto Serif JP", "Hiragino Mincho ProN", "Yu Mincho", "Yu Mincho", serif;
  --font-en: "Montserrat", "Noto Sans JP", Arial, sans-serif;

  /* Motion */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-slow: 0.9s;
  --dur-med: 0.6s;
  --dur-fast: 0.28s;

  /* Shadow */
  --shadow-card: 0 20px 48px rgba(18, 57, 92, 0.10);
  --shadow-hover: 0 34px 64px rgba(18, 57, 92, 0.16);
  --shadow-cta: 0 12px 28px rgba(223, 93, 33, 0.30);
}

/* ==========================================================================
   3. Base
   ========================================================================== */
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font-jp);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.95;                /* §2-1 日本語の組み対策 */
  letter-spacing: 0.04em;           /* §2-1 日本語の組み対策 */
  -webkit-font-smoothing: antialiased;
  font-feature-settings: "palt";
  overflow-x: hidden;               /* 巨大ゴースト文字対策 */
}
h1, h2, h3, h4, h5 { line-height: 1.35; color: var(--ink); font-weight: 900; letter-spacing: -0.005em; }
p { line-height: 2.0; }
strong { font-weight: 700; }
::selection { background: var(--aiyin-orange); color: #fff; }

/* ==========================================================================
   4. Utilities
   ========================================================================== */
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gutter); }
.wrap-narrow { max-width: var(--wrap-narrow); margin: 0 auto; padding: 0 var(--gutter); }
.en { font-family: var(--font-en); }
.serif { font-family: var(--font-serif); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.mt-8{margin-top:8px}.mt-16{margin-top:16px}.mt-24{margin-top:24px}.mt-32{margin-top:32px}
.mt-48{margin-top:48px}.mt-64{margin-top:64px}.mt-96{margin-top:96px}

/* ==========================================================================
   5. Reveal Animation（IntersectionObserverで.is-inクラス付与）
   ========================================================================== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity var(--dur-slow) var(--ease-out),
              transform var(--dur-slow) var(--ease-out);
  transition-delay: var(--reveal-delay, 0s);
  will-change: opacity, transform;
}
.reveal.is-in { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .parallax { transform: none !important; }
  html { scroll-behavior: auto; }
}

/* ==========================================================================
   6. Backgrounds
   ========================================================================== */
/* ドットグリッド背景（radial-gradient繰り返し・軽量） */
.bg-dot {
  background-image: radial-gradient(circle, rgba(18, 57, 92, 0.12) 1px, transparent 1.6px);
  background-size: 22px 22px;
  background-position: 0 0;
}
.bg-dot-soft {
  background-image: radial-gradient(circle, rgba(18, 57, 92, 0.07) 1px, transparent 1.6px);
  background-size: 22px 22px;
}

/* 巨大ゴースト文字（背景に薄いアウトラインテキスト） */
.ghost-text {
  position: absolute;
  font-family: var(--font-en);
  font-weight: 800;
  color: transparent;
  -webkit-text-stroke: 1px var(--aiyin-navy);
  opacity: 0.055;
  pointer-events: none;
  white-space: nowrap;
  line-height: 1;
  user-select: none;
  z-index: 0;
}

/* 斜め区切り帯 */
.slash-divider {
  position: relative;
  height: 96px;
  overflow: hidden;
}
.slash-divider::before {
  content: "";
  position: absolute;
  inset: -40% -10% -40% -10%;
  background: var(--paper-warm);
  transform: rotate(-2deg);
  z-index: 0;
}

/* ==========================================================================
   7. Mini bar（ヘッダー上のnavy帯）
   ========================================================================== */
.minibar {
  background: var(--aiyin-navy);
  color: #fff;
  font-size: 12px;
  padding: 8px var(--gutter);
  letter-spacing: 0.08em;
}
.minibar__inner {
  max-width: var(--wrap);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.minibar__lead { opacity: 0.92; }
.minibar__lead .accent { color: var(--aiyin-orange); font-weight: 700; }
.minibar__lang { opacity: 0.72; }
@media (max-width: 640px) {
  .minibar { font-size: 11px; padding: 6px var(--gutter); }
  .minibar__lang { display: none; }
}

/* ==========================================================================
   8. Header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
  transition: box-shadow var(--dur-fast) var(--ease-out),
              background var(--dur-fast) var(--ease-out);
}
.site-header.is-scrolled { box-shadow: 0 8px 32px rgba(18, 57, 92, 0.08); }

.header-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 14px var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-en);
  font-weight: 800;
}
.brand img { height: 32px; width: auto; }
.brand__jp {
  font-family: var(--font-jp);
  font-size: 11px;
  color: var(--ink-sub);
  font-weight: 500;
  letter-spacing: 0.04em;
  display: none;
}
@media (min-width: 900px) { .brand__jp { display: inline; } }

/* Nav (desktop) */
.nav {
  display: none;
  align-items: center;
  gap: 4px;
}
.nav__link {
  padding: 10px 14px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--ink);
  border-bottom: 2px solid transparent;
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}
.nav__link:hover { color: var(--aiyin-orange); border-bottom-color: var(--aiyin-orange); }
.nav__link.is-active { color: var(--aiyin-orange); border-bottom-color: var(--aiyin-orange); }
@media (min-width: 900px) { .nav { display: flex; } }

/* Hamburger */
.hamburger {
  display: flex;
  flex-direction: column;
  gap: 5px;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
}
.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  transition: transform var(--dur-fast) var(--ease-out),
              opacity var(--dur-fast) var(--ease-out);
}
.hamburger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.is-open span:nth-child(2) { opacity: 0; }
.hamburger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
@media (min-width: 900px) { .hamburger { display: none; } }

/* Mobile menu */
.mobile-menu {
  position: fixed;
  inset: 0;
  background: #fff;
  padding: 96px var(--gutter) 48px;
  z-index: 99;
  transform: translateX(100%);
  transition: transform var(--dur-med) var(--ease-out);
  overflow-y: auto;
}
.mobile-menu.is-open { transform: translateX(0); }
.mobile-menu__list { display: flex; flex-direction: column; gap: 8px; }
.mobile-menu__link {
  display: block;
  padding: 16px 8px;
  font-size: 18px;
  font-weight: 700;
  border-bottom: 1px solid var(--line);
}
.mobile-menu__cta {
  margin-top: 28px;
  display: block;
  text-align: center;
}
@media (min-width: 900px) { .mobile-menu { display: none; } }

/* ==========================================================================
   9. Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 26px;
  border-radius: 4px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  white-space: nowrap;
  transition: background var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out), transform var(--dur-fast) var(--ease-out),
              box-shadow var(--dur-fast) var(--ease-out);
}
.btn__arrow {
  display: inline-block;
  transition: transform var(--dur-fast) var(--ease-out);
}
.btn:hover .btn__arrow { transform: translateX(4px); }

.btn--fill {
  background: var(--aiyin-orange);
  color: #fff;
  box-shadow: 0 8px 20px rgba(223, 93, 33, 0.24);
}
.btn--fill:hover { background: var(--aiyin-orange-dark); box-shadow: var(--shadow-cta); transform: translateY(-1px); }

.btn--outline-navy {
  border: 1.5px solid var(--aiyin-navy);
  color: var(--aiyin-navy);
}
.btn--outline-navy:hover { background: var(--aiyin-navy); color: #fff; }

.btn--outline-white {
  border: 1.5px solid #fff;
  color: #fff;
}
.btn--outline-white:hover { background: #fff; color: var(--aiyin-navy); }

.btn--ghost {
  padding: 10px 0;
  border-bottom: 1.5px solid var(--ink);
  border-radius: 0;
  color: var(--ink);
}
.btn--ghost:hover { color: var(--aiyin-orange); border-bottom-color: var(--aiyin-orange); }

/* ==========================================================================
   10. Section common
   ========================================================================== */
.section { padding: 96px 0; position: relative; }
.section--tight { padding: 64px 0; }
.section--warm { background: var(--paper-warm); }
.section--soft { background: var(--paper-soft); }
.section--navy { background: var(--aiyin-navy); color: #fff; }

.section-head { margin-bottom: 48px; position: relative; }
.section-head__num {
  font-family: var(--font-en);
  font-weight: 200;
  font-size: clamp(80px, 12vw, 160px);
  color: var(--aiyin-navy);
  opacity: 0.06;
  line-height: 1;
  position: absolute;
  top: -32px;
  left: -12px;
  pointer-events: none;
  user-select: none;
  z-index: 0;
}
.section-head__label {
  position: relative;
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--aiyin-orange);
  display: inline-block;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--aiyin-orange);
  margin-bottom: 20px;
  z-index: 1;
}
.section-head__title {
  position: relative;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1.45;
  letter-spacing: 0.02em;
  z-index: 1;
}
.section-head__lead {
  position: relative;
  margin-top: 18px;
  color: var(--ink-sub);
  font-size: 15px;
  max-width: 60ch;
  z-index: 1;
}

/* ==========================================================================
   11. Hero (index)
   ========================================================================== */
.hero {
  position: relative;
  background: var(--paper-soft);
  padding: 72px 0 96px;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(18, 57, 92, 0.08) 1px, transparent 1.6px);
  background-size: 22px 22px;
  opacity: 0.9;
  z-index: 0;
}
.hero__ghost {
  top: 6%;
  right: -4%;
  font-size: clamp(180px, 30vw, 420px);
  letter-spacing: -0.03em;
}
.hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 48px;
  align-items: center;
  min-height: 480px;
}
@media (max-width: 900px) {
  .hero__grid { grid-template-columns: 1fr; gap: 32px; min-height: 0; }
}

.hero__vertical {
  writing-mode: vertical-rl;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.4em;
  color: var(--ink-sub);
  position: absolute;
  top: 24px;
  right: 24px;
  z-index: 2;
}
@media (max-width: 900px) { .hero__vertical { display: none; } }

.hero__kicker {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.28em;
  color: var(--aiyin-orange);
  margin-bottom: 24px;
}
.hero__decl {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(40px, 6.4vw, 84px);
  line-height: 1.18;
  color: var(--aiyin-navy);
  letter-spacing: 0.02em;
}
.hero__decl .dot { color: var(--aiyin-orange); }
.hero__stamp {
  margin-top: 20px;
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.28em;
  color: var(--ink-sub);
}
.hero__sub {
  margin-top: 24px;
  font-size: clamp(18px, 2.4vw, 26px);
  font-weight: 500;
  color: var(--ink);
  letter-spacing: 0.02em;
}
.hero__desc {
  margin-top: 20px;
  color: var(--ink-sub);
  font-size: 15px;
  max-width: 44ch;
}
.hero__cta {
  margin-top: 32px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hero__photo {
  position: relative;
  min-width: 0;
}
.hero__photo-card {
  position: relative;
  background: #fff;
  border-radius: 8px;
  padding: 28px;
  box-shadow: var(--shadow-card);
  will-change: transform;
}
.hero__photo-card img { border-radius: 4px; width: 100%; }
.hero__badge {
  position: absolute;
  top: 16px;
  left: 16px;
  background: var(--aiyin-orange);
  color: #fff;
  font-family: var(--font-jp);
  font-weight: 700;
  font-size: 12px;
  padding: 8px 14px;
  border-radius: 3px;
  letter-spacing: 0.04em;
  box-shadow: var(--shadow-cta);
  z-index: 3;
}
.hero__badge-en {
  display: block;
  font-family: var(--font-en);
  font-size: 9px;
  font-weight: 600;
  letter-spacing: 0.2em;
  opacity: 0.92;
  margin-bottom: 2px;
}

/* ==========================================================================
   12. Stats band
   ========================================================================== */
.stats {
  background: var(--aiyin-navy);
  color: #fff;
  padding: 56px 0;
  position: relative;
  overflow: hidden;
}
.stats__ghost {
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: clamp(140px, 24vw, 320px);
  color: transparent;
  -webkit-text-stroke: 1px #fff;
  opacity: 0.05;
}
.stats__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  text-align: center;
}
@media (max-width: 720px) {
  .stats__grid { grid-template-columns: repeat(2, 1fr); gap: 32px 16px; }
}
.stats__item { font-size: 14px; line-height: 1.6; font-weight: 500; }
.stats__item::before {
  content: "";
  display: block;
  width: 32px;
  height: 2px;
  background: var(--aiyin-orange);
  margin: 0 auto 14px;
}

/* ==========================================================================
   13. Product cards（非対称・格差レイアウト）
   ========================================================================== */
.products-grid {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 24px;
  align-items: stretch;
}
@media (max-width: 900px) {
  .products-grid { grid-template-columns: 1fr; }
}
.products-grid__side {
  display: grid;
  grid-template-rows: 1fr 1fr;
  gap: 24px;
}

.pcard {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 28px;
  transition: transform var(--dur-med) var(--ease-out),
              box-shadow var(--dur-med) var(--ease-out),
              border-color var(--dur-fast);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
.pcard:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); border-color: transparent; }
.pcard__tag {
  position: absolute;
  top: 18px;
  right: 18px;
  background: var(--aiyin-orange);
  color: #fff;
  font-family: var(--font-en);
  font-weight: 800;
  font-size: 10px;
  padding: 5px 10px;
  letter-spacing: 0.2em;
  border-radius: 2px;
}
.pcard__tag--muted {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink-sub);
}
.pcard__img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border-radius: 4px;
  background: var(--paper-soft);
  margin-bottom: 20px;
}
.pcard__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
}
.pcard__title {
  margin-top: 8px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.4;
  color: var(--ink);
}
.pcard__desc {
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.85;
  flex-grow: 1;
}
.pcard__link {
  margin-top: 20px;
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--aiyin-navy);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.pcard__link .arrow { transition: transform var(--dur-fast); }
.pcard:hover .pcard__link .arrow { transform: translateX(4px); }

/* C2 大カード用の追加スタイル */
.pcard--hero {
  padding: 40px;
  background: linear-gradient(135deg, #fff 0%, var(--paper-warm) 100%);
}
.pcard--hero .pcard__img { aspect-ratio: 5 / 3; margin-bottom: 28px; }
.pcard--hero .pcard__title { font-size: clamp(26px, 3vw, 34px); }
.pcard--hero .pcard__desc { font-size: 14px; }
@media (max-width: 480px) {
  .pcard--hero { padding: 28px 24px; }
}

/* C2 大カードの画像フレーム（バッジを画像左上に重ねるための基準枠） */
.pcard__img-frame { position: relative; }
.pcard--hero .pcard__img-frame { margin-bottom: 28px; }
.pcard--hero .pcard__img-frame .pcard__img { margin-bottom: 0; }

/* サイドカード（縦積み）用 */
.pcard--side { padding: 20px; }
.pcard--side .pcard__img { aspect-ratio: 4 / 3; margin-bottom: 14px; }
.pcard--side .pcard__title { font-size: 17px; }
.pcard--side .pcard__desc { font-size: 12px; margin-top: 6px; line-height: 1.7; }
.pcard--side .pcard__link { margin-top: 12px; font-size: 11px; }

/* ==========================================================================
   14. Feature stripe (C2の4アイコン)
   ========================================================================== */
.feature-stripe {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  padding: 48px 0;
}
@media (max-width: 720px) {
  .feature-stripe { grid-template-columns: repeat(2, 1fr); gap: 32px 20px; }
}
.fitem { text-align: left; }
.fitem__num {
  font-family: var(--font-en);
  font-weight: 200;
  font-size: clamp(52px, 6vw, 76px);
  line-height: 1;
  color: var(--aiyin-navy);
  letter-spacing: -0.02em;
}
.fitem__num .unit {
  font-size: 0.4em;
  font-weight: 600;
  color: var(--ink-sub);
  margin-left: 4px;
  letter-spacing: 0.06em;
}
.fitem__label {
  margin-top: 10px;
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
}
.fitem__desc {
  margin-top: 8px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.75;
}

/* ==========================================================================
   15. Company teaser
   ========================================================================== */
.teaser {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
  align-items: center;
}
@media (max-width: 900px) { .teaser { grid-template-columns: 1fr; gap: 32px; } }
.teaser__img {
  width: 100%;
  aspect-ratio: 5 / 4;
  object-fit: cover;
  border-radius: 4px;
}
.teaser__title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(24px, 3.2vw, 36px);
  line-height: 1.5;
}
.teaser__chips {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.chip {
  padding: 6px 12px;
  background: var(--paper-soft);
  border: 1px solid var(--line);
  font-size: 12px;
  color: var(--ink-sub);
  letter-spacing: 0.04em;
}

/* ==========================================================================
   16. News (index)
   ========================================================================== */
.news-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line);
}
.news-item {
  display: grid;
  grid-template-columns: 120px 100px 1fr;
  gap: 24px;
  padding: 20px 8px;
  border-bottom: 1px solid var(--line);
  align-items: center;
  transition: background var(--dur-fast) var(--ease-out);
}
.news-item:hover { background: var(--paper-soft); }
.news-item__date {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 13px;
  color: var(--ink-sub);
  letter-spacing: 0.1em;
}
.news-item__cat {
  font-family: var(--font-en);
  font-weight: 700;
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--aiyin-orange);
  border: 1px solid var(--aiyin-orange);
  padding: 4px 8px;
  text-align: center;
}
.news-item__title { font-size: 14px; font-weight: 500; color: var(--ink); }
@media (max-width: 720px) {
  .news-item { grid-template-columns: 90px 88px; grid-template-rows: auto auto; gap: 8px 12px; padding: 16px 4px; }
  .news-item__title { grid-column: 1 / -1; }
}

/* ==========================================================================
   17. CTA band
   ========================================================================== */
.ctaband {
  background: linear-gradient(120deg, var(--aiyin-orange) 0%, var(--aiyin-orange-dark) 100%);
  color: #fff;
  padding: 72px 0;
  position: relative;
  overflow: hidden;
}
.ctaband__ghost {
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: clamp(140px, 22vw, 300px);
  -webkit-text-stroke: 1px #fff;
  color: transparent;
  opacity: 0.08;
}
.ctaband__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 40px;
  align-items: center;
}
@media (max-width: 720px) { .ctaband__grid { grid-template-columns: 1fr; text-align: center; } }
.ctaband__title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.5;
}
.ctaband__lead {
  margin-top: 12px;
  font-size: 14px;
  opacity: 0.92;
  line-height: 1.9;
}
.ctaband__actions {
  display: flex;
  gap: 14px;
  justify-content: flex-end;
  flex-wrap: wrap;
}
@media (max-width: 720px) { .ctaband__actions { justify-content: center; } }

/* ==========================================================================
   18. Footer
   ========================================================================== */
.site-footer {
  background: var(--aiyin-navy);
  color: #fff;
  padding: 72px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}
@media (max-width: 720px) { .footer-grid { grid-template-columns: 1fr; gap: 32px; } }
.footer-brand__name {
  font-family: var(--font-en);
  font-weight: 800;
  font-size: 22px;
  letter-spacing: 0.02em;
}
.footer-brand__jp {
  margin-top: 6px;
  font-size: 13px;
  opacity: 0.72;
}
.footer-brand__addr {
  margin-top: 20px;
  font-size: 12px;
  line-height: 1.85;
  opacity: 0.8;
}
.footer-brand__contact {
  margin-top: 12px;
  font-size: 12px;
  opacity: 0.8;
}
.footer-brand__contact a { color: var(--aiyin-orange); font-weight: 700; }

.footer-col__title {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
  margin-bottom: 18px;
}
.footer-col__list { display: flex; flex-direction: column; gap: 12px; }
.footer-col__list a {
  font-size: 13px;
  opacity: 0.88;
  transition: opacity var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}
.footer-col__list a:hover { color: var(--aiyin-orange); opacity: 1; }

.footer-bottom {
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  opacity: 0.6;
  letter-spacing: 0.06em;
  flex-wrap: wrap;
  gap: 12px;
}

/* ==========================================================================
   19. Breadcrumb（下層ページ）
   ========================================================================== */
.breadcrumb {
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-en);
  font-size: 12px;
  color: var(--ink-sub);
  letter-spacing: 0.1em;
}
.breadcrumb__inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: flex;
  gap: 12px;
  align-items: center;
}
.breadcrumb a { color: var(--ink-sub); transition: color var(--dur-fast); }
.breadcrumb a:hover { color: var(--aiyin-orange); }
.breadcrumb__sep { opacity: 0.5; }
.breadcrumb__current { color: var(--ink); font-weight: 600; }

/* ==========================================================================
   20. Product page (c2.html) 専用
   ========================================================================== */
.phero {
  position: relative;
  background: var(--paper-warm);
  padding: 72px 0 96px;
  overflow: hidden;
}
.phero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(18, 57, 92, 0.06) 1px, transparent 1.6px);
  background-size: 22px 22px;
  opacity: 0.9;
}
.phero__ghost {
  bottom: -8%;
  left: -4%;
  font-size: clamp(200px, 38vw, 540px);
  letter-spacing: -0.04em;
}
.phero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 56px;
  align-items: center;
}
@media (max-width: 900px) { .phero__grid { grid-template-columns: 1fr; gap: 32px; } }
.phero__meta {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--aiyin-orange);
}
.phero__title {
  margin-top: 20px;
  font-family: var(--font-en);
  font-weight: 800;
  font-size: clamp(80px, 12vw, 160px);
  line-height: 0.95;
  color: var(--aiyin-navy);
  letter-spacing: -0.02em;
}
.phero__tag {
  margin-top: 12px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(18px, 2.2vw, 24px);
  color: var(--ink);
}
.phero__lead {
  margin-top: 24px;
  color: var(--ink-sub);
  font-size: 15px;
  max-width: 44ch;
  line-height: 2;
}
.phero__cta {
  margin-top: 32px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}
.phero__debut {
  margin-top: 24px;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 3px;
  font-size: 12px;
  color: var(--ink-sub);
}
.phero__debut::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--aiyin-orange);
  animation: pulse 2s var(--ease-out) infinite;
}
@keyframes pulse {
  0%,100% { opacity: 0.4; transform: scale(0.9); }
  50% { opacity: 1; transform: scale(1.1); }
}
.phero__photo {
  position: relative;
  min-width: 0;
}
.phero__photo img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 4px;
  box-shadow: var(--shadow-card);
}

/* Feature alternating（左右交互） */
.frow {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
  margin: 96px 0;
}
@media (max-width: 900px) {
  .frow { grid-template-columns: 1fr; gap: 32px; margin: 56px 0; }
}
.frow--reverse .frow__text { order: 2; }
.frow--reverse .frow__img { order: 1; }
@media (max-width: 900px) {
  .frow--reverse .frow__text, .frow--reverse .frow__img { order: initial; }
}
.frow__img {
  position: relative;
}
.frow__img img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 4px;
  box-shadow: var(--shadow-card);
}
.frow__num {
  position: absolute;
  top: -32px;
  left: -12px;
  font-family: var(--font-en);
  font-weight: 200;
  font-size: clamp(80px, 10vw, 140px);
  color: var(--aiyin-navy);
  opacity: 0.08;
  line-height: 1;
  z-index: 0;
  pointer-events: none;
}
.frow__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--aiyin-orange);
}
.frow__title {
  margin-top: 16px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(26px, 3.4vw, 40px);
  line-height: 1.4;
  letter-spacing: 0.02em;
}
.frow__title .accent { color: var(--aiyin-orange); }
.frow__lead {
  margin-top: 20px;
  color: var(--ink-sub);
  line-height: 2;
  font-size: 15px;
}

/* Usage grid（4シーン） */
.usage-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
@media (max-width: 900px) { .usage-grid { grid-template-columns: repeat(2, 1fr); } }
.ucard {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
  transition: transform var(--dur-med) var(--ease-out),
              box-shadow var(--dur-med) var(--ease-out);
}
.ucard:hover { transform: translateY(-4px); box-shadow: var(--shadow-card); }
.ucard__img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background: var(--paper-soft);
}
.ucard__body { padding: 20px; }
.ucard__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 10px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
}
.ucard__title {
  margin-top: 8px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.5;
}
.ucard__desc {
  margin-top: 8px;
  font-size: 12px;
  color: var(--ink-sub);
  line-height: 1.8;
}

/* Setup steps（3ステップ） */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  position: relative;
}
@media (max-width: 720px) { .steps { grid-template-columns: 1fr; gap: 24px; } }
.step {
  background: #fff;
  padding: 32px 28px;
  border: 1px solid var(--line);
  border-radius: 4px;
}
.step__num {
  font-family: var(--font-en);
  font-weight: 200;
  font-size: 56px;
  line-height: 1;
  color: var(--aiyin-orange);
  letter-spacing: -0.02em;
}
.step__img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 4px;
  margin-top: 16px;
}
.step__title {
  margin-top: 20px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.5;
}
.step__desc {
  margin-top: 8px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.85;
}

/* Spec table */
.spec-wrap {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}
.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
.spec-table th,
.spec-table td {
  padding: 18px 24px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.spec-table tr:last-child th,
.spec-table tr:last-child td { border-bottom: none; }
.spec-table th {
  width: 40%;
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-sub);
  background: var(--paper-soft);
  text-transform: uppercase;
}
.spec-table td { font-weight: 500; color: var(--ink); overflow-wrap: break-word; }
.spec-table td .jp { font-family: var(--font-jp); }
@media (max-width: 720px) {
  .spec-table th, .spec-table td { padding: 14px 16px; font-size: 13px; }
  .spec-table th { width: 42%; font-size: 10px; }
}

/* Consumable */
.consumable {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
@media (max-width: 720px) { .consumable { grid-template-columns: 1fr; } }
.ccard {
  background: var(--paper-soft);
  padding: 32px;
  border-radius: 4px;
}
.ccard__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
}
.ccard__title {
  margin-top: 8px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 20px;
}
.ccard__desc {
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.85;
}
.ccard__note {
  margin-top: 14px;
  font-size: 11px;
  color: var(--ink-sub);
  opacity: 0.72;
}

/* ==========================================================================
   21. Focus / Accessibility
   ========================================================================== */
:focus-visible {
  outline: 2px solid var(--aiyin-orange);
  outline-offset: 2px;
}

/* ==========================================================================
   22. Print
   ========================================================================== */
@media print {
  .site-header, .ctaband, .site-footer, .minibar { display: none; }
  .hero { padding: 24px 0; }
  body { color: #000; }
}

/* ==========================================================================
   23. P3/P4 追加（company / partners / contact / products一覧・a4l・b23）
   実装：ロクサス（Sonnet 5）
   ========================================================================== */

/* --- Info table（日本語見出しの会社概要・沿革テーブル） --- */
.info-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}
.info-table th,
.info-table td {
  padding: 18px 24px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  font-size: 14px;
}
.info-table tr:last-child th,
.info-table tr:last-child td { border-bottom: none; }
.info-table th {
  width: 30%;
  font-family: var(--font-jp);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink-sub);
  background: var(--paper-soft);
}
.info-table td { font-weight: 500; color: var(--ink); line-height: 1.9; overflow-wrap: break-word; }
.info-table td a { color: var(--aiyin-orange); font-weight: 700; text-decoration: underline; }
@media (max-width: 720px) {
  .info-table th, .info-table td { padding: 14px 16px; font-size: 13px; }
  .info-table th { width: 36%; }
}

/* --- Teaser reverse（会社2階建てセクションで画像左右を入れ替え） --- */
.teaser--reverse .teaser__img { order: 2; }
.teaser--reverse .teaser__text { order: 1; }
@media (max-width: 900px) {
  .teaser--reverse .teaser__img, .teaser--reverse .teaser__text { order: initial; }
}

/* --- Steps 4カラム variant（partners.html 取引の流れ） --- */
.steps--4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .steps--4 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .steps--4 { grid-template-columns: 1fr; } }

/* --- Reason cards（partners.html AiYinと組む理由・3点） --- */
.reason-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
@media (max-width: 900px) { .reason-grid { grid-template-columns: 1fr; } }
.reason-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 32px 28px;
  transition: transform var(--dur-med) var(--ease-out), box-shadow var(--dur-med) var(--ease-out);
}
.reason-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-card); }
.reason-card__num {
  font-family: var(--font-en);
  font-weight: 200;
  font-size: 44px;
  color: var(--aiyin-orange);
  line-height: 1;
}
.reason-card__title {
  margin-top: 16px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.5;
}
.reason-card__desc {
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.85;
}

/* --- FAQ（details/summary） --- */
.faq-list { display: grid; gap: 14px; }
.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 4px 24px;
}
.faq-item summary {
  padding: 18px 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 15px;
  cursor: pointer;
  color: var(--ink);
  list-style: none;
  position: relative;
  padding-right: 32px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 0;
  top: 14px;
  font-family: var(--font-en);
  font-weight: 600;
  color: var(--aiyin-orange);
  font-size: 20px;
  line-height: 1;
  transition: transform var(--dur-fast) var(--ease-out);
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item__a {
  padding: 0 0 20px;
  color: var(--ink-sub);
  font-size: 14px;
  line-height: 1.9;
  max-width: 60ch;
}

/* --- Contact cards（contact.html 直接連絡） --- */
.contact-card {
  padding: 24px;
  background: var(--paper-soft);
  border: 1px solid var(--line);
  border-radius: 4px;
}
.contact-card + .contact-card { margin-top: 16px; }
.contact-card__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-sub);
  margin-bottom: 8px;
}
.contact-card__value { font-size: 19px; font-weight: 700; }
.contact-card__value a { color: var(--aiyin-orange); }
.contact-card__value--muted { font-size: 15px; font-weight: 700; color: var(--ink-sub); }
.contact-card__note {
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-sub);
  line-height: 1.85;
}

/* --- Form（contact.html お問い合わせフォーム） --- */
.form-note-box {
  padding: 18px 20px;
  background: var(--aiyin-orange-soft);
  border: 1px solid rgba(223, 93, 33, 0.24);
  border-radius: 4px;
  font-size: 13px;
  line-height: 1.85;
  color: var(--ink);
  margin-bottom: 28px;
}
.form-note-box a { color: var(--aiyin-orange); font-weight: 700; text-decoration: underline; }
.form-grid { display: grid; gap: 20px; }
.form-field label {
  display: block;
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--ink);
}
.form-field .req {
  margin-left: 8px;
  font-size: 10px;
  font-weight: 700;
  color: var(--aiyin-orange);
  border: 1px solid var(--aiyin-orange);
  padding: 2px 6px;
  border-radius: 2px;
  letter-spacing: 0.04em;
  vertical-align: middle;
}
.form-field input,
.form-field select,
.form-field textarea {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 4px;
  font-size: 14px;
  background: #fff;
  color: var(--ink);
  transition: border-color var(--dur-fast);
}
.form-field input:focus,
.form-field select:focus,
.form-field textarea:focus { border-color: var(--aiyin-orange); }
.form-field textarea { min-height: 140px; resize: vertical; }
.form-submit { margin-top: 8px; width: 100%; justify-content: center; opacity: 0.5; cursor: not-allowed; }

/* --- Lineup note（products/index.html 今後のラインナップ） --- */
.lineup-note {
  margin-top: 40px;
  padding: 40px 32px;
  background: var(--paper-warm);
  border: 1px dashed var(--line);
  border-radius: 4px;
  text-align: center;
}
.lineup-note__label {
  font-family: var(--font-en);
  font-weight: 600;
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--aiyin-orange);
}
.lineup-note__text {
  margin-top: 14px;
  font-size: 15px;
  color: var(--ink-sub);
  line-height: 1.9;
  max-width: 56ch;
  margin-left: auto;
  margin-right: auto;
}

/* --- Usage grid 3カラム variant（a4l.html ギャラリー用） --- */
.usage-grid--3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 900px) { .usage-grid--3 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .usage-grid--3 { grid-template-columns: 1fr; } }

/* --- Products index page: 大カード内 spec mini list（b23簡易特徴用） --- */
.mini-feats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px 24px;
}
@media (max-width: 560px) { .mini-feats { grid-template-columns: 1fr; } }
.mini-feats li {
  padding-left: 20px;
  position: relative;
  font-size: 14px;
  color: var(--ink-sub);
  line-height: 1.8;
}
.mini-feats li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 2px;
  background: var(--aiyin-orange);
}