/* =========================================================
   Hidden North — 会社紹介サイト
   Design tokens are fixed per the handoff spec.
   Palette (4 values only):
     墨黑  #141312   雪白 #FBFAF8
     七竈紅(晝) #A5303A   七竈紅(夜) #C4444F
   ========================================================= */

:root {
  --ink: #141312;
  --snow: #FBFAF8;
  --rowan-day: #A5303A;
  --rowan-night: #C4444F;
  --rowan-deep: #8A2731;

  --hairline: rgba(20, 19, 18, .16);
  --hairline-row: rgba(20, 19, 18, .14);
  --hairline-top: rgba(20, 19, 18, .3);
  --text-secondary: rgba(20, 19, 18, .8);
  --text-body: rgba(20, 19, 18, .88);
  --label: rgba(20, 19, 18, .55);
  --address: rgba(20, 19, 18, .62);
  --on-dark: rgba(251, 250, 248, .78);

  --serif-ja: 'Noto Serif JP', serif;
  --serif-tc: 'Noto Serif TC', serif;
  --sans-ja: 'Noto Sans JP', sans-serif;
  --sans-tc: 'Noto Sans TC', sans-serif;
  --fraunces: 'Fraunces', serif;
  --dm: 'DM Sans', sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--snow);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--ink); text-decoration: none; }
a:hover { color: var(--rowan-day); }
::selection { background: rgba(165, 48, 58, .16); }

img { display: block; }

/* ---- Language visibility toggle ---- */
html[data-lang="ja"] .lang-zh,
html[data-lang="zh"] .lang-ja { display: none; }

/* Serif/sans helpers bound to active language */
html[data-lang="ja"] .serif { font-family: var(--serif-ja); }
html[data-lang="zh"] .serif { font-family: var(--serif-tc); }
html[data-lang="ja"] .sans  { font-family: var(--sans-ja); }
html[data-lang="zh"] .sans  { font-family: var(--sans-tc); }

/* =========================================================
   Eyebrow / section headings shared
   ========================================================= */
.eyebrow {
  font-family: var(--fraunces);
  font-weight: 500;
  font-size: 12.5px;
  letter-spacing: .42em;
  color: var(--rowan-day);
}
.section-h2 {
  margin: 16px 0 0;
  font-weight: 600;
  font-size: clamp(25px, 3vw, 33px);
  letter-spacing: .14em;
}

/* =========================================================
   0. Hero + nav
   ========================================================= */
.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--ink);
  overflow: hidden;
}
/* Full-bleed background photo, forced monochrome per spec.
   To swap the photo, replace assets/hero.jpg (2560×1440, 16:9). */
.hero__bg {
  position: absolute;
  inset: 0;
  background: #141312 url("assets/hero.jpg") center / cover no-repeat;
  filter: grayscale(1) contrast(1.04) brightness(.9);
}

.hero__scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg,
    rgba(20, 19, 18, .62) 0%,
    rgba(20, 19, 18, .24) 42%,
    rgba(20, 19, 18, .58) 100%);
  pointer-events: none;
}

.nav {
  position: absolute;
  top: 0; left: 0; right: 0;
  z-index: 4;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  padding: 24px clamp(22px, 4vw, 54px);
}
.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  color: var(--snow);
}
.brand:hover { color: var(--snow); opacity: .85; }
.brand img { height: 34px; }
.brand__word { display: flex; align-items: baseline; gap: 11px; }
.brand__latin {
  font-family: var(--fraunces);
  font-weight: 500;
  font-size: 18px;
  letter-spacing: .22em;
}
.brand__cjk {
  font-family: var(--serif-tc), var(--serif-ja);
  font-size: 14px;
  letter-spacing: .3em;
}

.nav__right {
  display: flex;
  align-items: center;
  gap: clamp(16px, 2.6vw, 34px);
  flex-wrap: wrap;
}
.nav__links {
  display: flex;
  gap: clamp(16px, 2.6vw, 34px);
  font-size: 13.5px;
  letter-spacing: .14em;
}
.nav__links a { color: var(--snow); }
.nav__links a:hover { color: var(--snow); opacity: .72; }

.lang-toggle {
  display: flex;
  align-items: center;
  gap: 4px;
  border: 1px solid rgba(251, 250, 248, .4);
  border-radius: 999px;
  padding: 4px 5px;
}
.lang-toggle button {
  font-family: var(--dm), var(--sans-ja), var(--sans-tc);
  font-size: 12.5px;
  letter-spacing: .06em;
  cursor: pointer;
  border: none;
  border-radius: 999px;
  padding: 5px 13px;
  transition: all .25s;
  background: transparent;
  color: rgba(251, 250, 248, .8);
}
.lang-toggle button[aria-pressed="true"] {
  background: rgba(251, 250, 248, .94);
  color: var(--ink);
}

.hero__title {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 130px 24px 90px;
  color: var(--snow);
}
.hero__title h1 {
  margin: 0;
  font-weight: 500;
  font-size: clamp(30px, 4.6vw, 54px);
  letter-spacing: .14em;
  line-height: 1.6;
  text-wrap: pretty;
}

/* =========================================================
   Generic section wrappers
   ========================================================= */
.section { background: var(--snow); }
.wrap-880 { max-width: 880px; margin: 0 auto; }
.wrap-720 { max-width: 720px; margin: 0 auto; text-align: center; }

/* 1. 理念 */
.philosophy { padding: clamp(110px, 14vw, 180px) 28px; }
.philosophy .lead {
  margin: 0;
  font-weight: 500;
  font-size: clamp(19px, 2.3vw, 25px);
  line-height: 2.3;
  letter-spacing: .07em;
  text-wrap: pretty;
}
.philosophy .rule {
  width: 28px; height: 2px;
  background: var(--rowan-day);
  margin: 56px auto;
}
.philosophy .body {
  margin: 0;
  font-size: clamp(15.5px, 1.5vw, 17.5px);
  line-height: 2.4;
  letter-spacing: .05em;
  color: var(--text-body);
  text-wrap: pretty;
}
.philosophy .body--emph {
  margin: 46px 0 0;
  font-weight: 600;
  color: var(--ink);
}

/* 2. 事業内容 */
.business { padding: 0 28px clamp(90px, 11vw, 140px); }
.biz-list {
  margin-top: 60px;
  border-top: 1px solid var(--hairline);
}
.biz-item {
  display: grid;
  grid-template-columns: clamp(52px, 8vw, 92px) 1fr;
  gap: 14px;
  padding: 38px 0;
  border-bottom: 1px solid var(--hairline);
}
.biz-item__num {
  font-family: var(--fraunces);
  font-size: 19px;
  color: var(--rowan-day);
  line-height: 1.6;
}
.biz-item h3 {
  margin: 0;
  font-weight: 600;
  font-size: 19px;
  letter-spacing: .06em;
  line-height: 1.7;
}
.biz-item p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.95;
  letter-spacing: .02em;
  color: var(--text-secondary);
  text-wrap: pretty;
}

/* 3. 会社概要 */
.company { padding: 0 28px clamp(100px, 12vw, 150px); }
.facts {
  margin-top: 56px;
  border-top: 1px solid var(--hairline-top);
}
.facts__row {
  display: grid;
  grid-template-columns: minmax(110px, 190px) 1fr;
  gap: 18px;
  padding: 22px 4px;
  border-bottom: 1px solid var(--hairline-row);
}
.facts__label {
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .12em;
  color: var(--label);
  padding-top: 2px;
}
.facts__value {
  font-size: 15px;
  line-height: 1.9;
}

/* 4. 代表挨拶 */
.greeting { padding: 0 28px clamp(110px, 13vw, 170px); }
.greeting .msg {
  margin: 54px 0 0;
  font-size: clamp(17px, 1.9vw, 21px);
  line-height: 2.4;
  letter-spacing: .06em;
  text-wrap: pretty;
}
.greeting .sign {
  margin: 44px 0 0;
  font-size: 14px;
  letter-spacing: .14em;
  color: rgba(20, 19, 18, .7);
}

/* 5. 聯絡 */
.contact { padding: 0 28px clamp(120px, 14vw, 180px); }
.contact .desc {
  margin: 36px 0 0;
  font-size: 15px;
  line-height: 2;
  letter-spacing: .04em;
  color: var(--text-secondary);
}
.contact__cta { margin-top: 44px; }
.contact__cta a {
  font-family: var(--dm), var(--sans-ja), sans-serif;
  font-weight: 500;
  font-size: clamp(21px, 2.8vw, 28px);
  letter-spacing: .01em;
  color: var(--rowan-day);
  border-bottom: 1px solid rgba(165, 48, 58, .45);
  padding-bottom: 7px;
}
.contact__cta a:hover {
  color: var(--rowan-deep);
  border-bottom-color: var(--rowan-deep);
}
.contact__addr {
  margin: 40px 0 0;
  font-family: var(--sans-ja), var(--sans-tc);
  font-size: 14px;
  letter-spacing: .1em;
  color: var(--address);
}

/* 6. Footer */
.footer {
  background: var(--ink);
  color: var(--on-dark);
  padding: 76px 28px 58px;
}
.footer__inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
  text-align: center;
}
.footer__brand { display: flex; align-items: center; gap: 14px; }
.footer__brand img { height: 38px; }
.footer__word {
  display: flex;
  align-items: baseline;
  gap: 11px;
  color: var(--snow);
}
.footer__word .brand__latin { font-size: 17px; }
.footer__word .brand__cjk { font-size: 13.5px; }
.footer__lines {
  font-family: var(--sans-ja);
  font-size: 13.5px;
  letter-spacing: .06em;
  line-height: 2.1;
}
.footer__lines a { color: var(--on-dark); }
.footer__lines a:hover { color: var(--rowan-night); }
.footer__copy {
  font-family: var(--dm);
  font-size: 12px;
  letter-spacing: .16em;
  color: rgba(251, 250, 248, .48);
}

/* Reduced-motion respect */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .lang-toggle button { transition: none; }
}