:root {
  --bg: #f2f0ea;
  --paper: #f8f7f3;
  --ink: #121212;
  --muted: #6e6b64;
  --line: #c9c5bb;
  --accent: #ff5a1f;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
small { font-size: .7em; font-weight: 500; letter-spacing: .05em; color: var(--muted); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 34px;
  border-bottom: 1px solid rgba(18,18,18,.12);
  background: rgba(242,240,234,.9);
  backdrop-filter: blur(12px);
}
.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border: 1.5px solid var(--ink);
  border-radius: 50%;
  font-weight: 800;
}
.brand-name { font-size: 13px; font-weight: 700; letter-spacing: .04em; }
.brand-name small { display: block; margin-top: 2px; font-size: 9px; letter-spacing: .13em; }
.nav { display: flex; gap: 28px; font-size: 12px; font-weight: 700; letter-spacing: .04em; }
.nav a { position: relative; }
.nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%; bottom: -5px;
  height: 1px; background: var(--ink);
  transition: right .2s ease;
}
.nav a:hover::after { right: 0; }

main { overflow: hidden; }
.hero {
  min-height: 780px;
  padding: 86px 34px 32px;
  border-bottom: 1px solid var(--line);
  position: relative;
}
.hero-kicker {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--muted);
}
.eyebrow {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .03em;
}
.eyebrow span {
  margin-left: 8px;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: .14em;
  color: var(--muted);
}
.hero h1 {
  margin: 36px 0 14px;
  font-size: clamp(72px, 11.5vw, 168px);
  line-height: .86;
  letter-spacing: -.07em;
  font-weight: 800;
}
.hero h1 span { display: block; }
.hero h1 span:nth-child(2) { margin-left: 8vw; }
.hero h1 span:nth-child(3) { margin-left: 16vw; }
.hero-caption {
  margin: 20px 0 0;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--muted);
}
.hero-meta {
  position: relative;
  z-index: 2;
  max-width: 600px;
  margin-left: auto;
  margin-top: 34px;
  font-size: 17px;
  line-height: 1.8;
}
.hero-meta p { margin: 0 0 10px; }
.hero-en { color: var(--muted); font-size: 12px; letter-spacing: .03em; }
.hero-graphic { position: absolute; inset: auto 0 0; height: 330px; opacity: .28; }
.hero-graphic svg { width: 100%; height: 100%; fill: none; stroke: var(--ink); stroke-width: 1.4; }

.intro,
.feature-section,
.grid-section,
.photo-section,
.closing {
  padding: 90px 34px;
  border-bottom: 1px solid var(--line);
}
.intro {
  display: grid;
  grid-template-columns: 90px minmax(0, 840px);
  gap: 36px;
}
.section-index {
  font-family: Georgia, serif;
  font-style: italic;
  font-size: 20px;
  color: var(--muted);
}
.intro h2,
.section-head h2,
.closing h2 {
  margin: 12px 0 22px;
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  font-weight: 500;
  letter-spacing: -.04em;
}
.intro h2 { font-size: clamp(38px, 4.8vw, 68px); line-height: 1.12; }
.intro-copy > p:last-child {
  max-width: 690px;
  margin-top: 28px;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.9;
}
.section-head {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 36px;
  margin-bottom: 54px;
}
.section-head h2 { font-size: clamp(34px, 4.2vw, 60px); line-height: 1.18; }

.bike-card {
  display: grid;
  grid-template-columns: 1.35fr .65fr;
  background: var(--paper);
  border: 1px solid var(--line);
}
.bike-visual {
  position: relative;
  min-height: 500px;
  overflow: hidden;
  border-right: 1px solid var(--line);
}
.bike-photo {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.bike-visual.has-photo .bike-placeholder { display: none; }
.bike-placeholder {
  width: 100%; height: 100%; min-height: 500px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 8px;
  background:
    linear-gradient(135deg, transparent 49.7%, rgba(18,18,18,.18) 50%, transparent 50.3%),
    linear-gradient(45deg, transparent 49.7%, rgba(18,18,18,.18) 50%, transparent 50.3%);
  color: var(--muted);
  text-align: center;
  padding: 20px;
}
.bike-placeholder span { font-size: 14px; letter-spacing: .08em; font-weight: 700; }
.bike-placeholder small { font-size: 12px; }
.bike-info { padding: 38px; display: flex; flex-direction: column; justify-content: center; }
.bike-info h3 { font-size: 34px; margin: 12px 0 30px; line-height: 1.15; font-weight: 600; }
dl { margin: 0; }
dl div { display: grid; grid-template-columns: 110px 1fr; padding: 14px 0; border-top: 1px solid var(--line); }
dt { font-size: 12px; font-weight: 700; color: var(--muted); }
dt small { display: block; margin-top: 2px; font-size: 8px; letter-spacing: .1em; }
dd { margin: 0; font-size: 14px; }
.muted { margin-top: 28px; color: var(--muted); font-size: 13px; line-height: 1.7; }

.photo-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.photo-grid figure {
  margin: 0;
  min-height: 320px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--paper);
}
.photo-grid .photo-wide { grid-column: 1 / -1; min-height: 480px; }
.photo-grid img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.cards { display: grid; grid-template-columns: 1.4fr .6fr; gap: 16px; }
.cards.three { grid-template-columns: repeat(3, 1fr); }
.note-card {
  min-height: 280px;
  padding: 28px;
  border: 1px solid var(--line);
  background: var(--paper);
  display: flex;
  flex-direction: column;
}
.note-card.large { min-height: 360px; background: var(--ink); color: #f7f5ee; }
.card-no { font-size: 11px; letter-spacing: .05em; font-weight: 700; color: var(--muted); }
.card-no small { margin-left: 6px; font-size: 8px; letter-spacing: .12em; }
.note-card.large .card-no { color: #aaa; }
.note-card h3 { margin: 58px 0 14px; font-size: 30px; font-weight: 600; letter-spacing: -.03em; }
.note-card h3 small { display: block; margin-top: 7px; font-size: 10px; letter-spacing: .13em; }
.note-card p { max-width: 440px; color: var(--muted); line-height: 1.75; font-size: 14px; }
.note-card.large p { color: #bbb; }
.card-link { margin-top: auto; font-size: 11px; font-weight: 700; }
.card-link small { margin-left: 6px; font-size: 8px; letter-spacing: .1em; }

.closing { min-height: 480px; display: flex; flex-direction: column; justify-content: center; }
.closing h2 { font-size: clamp(64px, 9vw, 132px); line-height: .92; margin-top: 24px; }

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 28px 34px 40px;
  font-size: 11px;
  color: var(--muted);
}
.site-footer small { margin-left: 6px; font-size: 8px; letter-spacing: .12em; }
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; justify-content: flex-end; }
.footer-links a { text-decoration: underline; text-underline-offset: 3px; }
.mps-link { display: inline-flex; align-items: center; gap: 5px; }
.mps-link img { width: 14px; height: 14px; object-fit: contain; flex: 0 0 auto; }

@media (max-width: 820px) {
  .site-header { padding: 16px 18px; }
  .nav { gap: 14px; }
  .nav a:nth-child(3) { display: none; }
  .brand-name { display: none; }
  .hero { min-height: 620px; padding: 60px 18px 26px; }
  .hero h1 { font-size: clamp(58px, 17vw, 104px); }
  .hero h1 span:nth-child(2),
  .hero h1 span:nth-child(3) { margin-left: 0; }
  .hero-meta { margin-top: 48px; }
  .intro, .feature-section, .grid-section, .photo-section, .closing { padding: 64px 18px; }
  .intro, .section-head { grid-template-columns: 52px 1fr; gap: 16px; }
  .bike-card { grid-template-columns: 1fr; }
  .bike-visual { border-right: 0; border-bottom: 1px solid var(--line); min-height: 340px; }
  .bike-placeholder { min-height: 340px; }
  .bike-info { padding: 26px; }
  .photo-grid { grid-template-columns: 1fr; }
  .photo-grid .photo-wide { grid-column: auto; min-height: 320px; }
  .cards, .cards.three { grid-template-columns: 1fr; }
  .note-card, .note-card.large { min-height: 260px; }
  .site-footer { flex-direction: column; padding: 24px 18px 32px; }
  .footer-links { justify-content: flex-start; flex-direction: column; gap: 8px; }
}