:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --ink: #182420;
  --muted: #5f6b68;
  --paper: #ffffff;
  --surface: #f4f7f5;
  --line: rgba(24, 36, 32, 0.14);
  --accent: #1f5f70;
  --accent-strong: #123842;
  --shadow: 0 24px 60px rgba(20, 32, 45, 0.12);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--font-sans);
  line-height: 1.65;
  letter-spacing: 0;
}
a { color: inherit; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(18px, 4vw, 56px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  font-weight: 800;
  text-decoration: none;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  color: #fff;
  background: var(--accent-strong);
}
nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: flex-end;
  font-size: 14px;
}
nav a { color: var(--muted); text-decoration: none; }
nav a:hover { color: var(--ink); }
main { overflow-x: clip; }
.hero-media {
  width: 100%;
  aspect-ratio: 16 / 7;
  overflow: hidden;
  background: var(--surface);
}
.hero-media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  object-position: center;
  padding: clamp(28px, 8vw, 88px);
}
.hero,
.section,
.page-title,
.site-footer {
  padding: clamp(44px, 8vw, 96px) clamp(18px, 5vw, 72px);
}
.band { background: var(--surface); }
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(280px, 0.8fr);
  gap: clamp(28px, 6vw, 72px);
  align-items: center;
  min-height: 72vh;
}
.project-hero {
  background: linear-gradient(180deg, var(--surface), #fff);
}
.eyebrow {
  margin: 0 0 12px;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}
h1,
h2,
h3,
p { margin-top: 0; }
h1 {
  max-width: 920px;
  margin-bottom: 22px;
  font-size: clamp(40px, 7vw, 82px);
  line-height: 1.02;
  letter-spacing: 0;
  overflow-wrap: anywhere;
}
h2 {
  max-width: 760px;
  margin-bottom: 18px;
  font-size: clamp(28px, 4vw, 48px);
  line-height: 1.12;
}
h3 { margin-bottom: 8px; font-size: 20px; line-height: 1.25; }
.lead {
  max-width: 720px;
  color: var(--muted);
  font-size: clamp(18px, 2.2vw, 23px);
}
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 11px 18px;
  border: 1px solid var(--accent-strong);
  border-radius: 8px;
  color: #fff;
  background: var(--accent-strong);
  font-weight: 760;
  text-decoration: none;
}
.button.ghost,
.button.secondary {
  color: var(--accent-strong);
  background: transparent;
}
.hero-panel,
.signal-list {
  padding: clamp(22px, 4vw, 38px);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}
.hero-panel span,
.signal-list strong {
  display: block;
  color: var(--accent-strong);
  font-weight: 800;
}
.hero-panel strong {
  display: block;
  margin: 8px 0 14px;
  font-size: clamp(24px, 3vw, 38px);
  line-height: 1.12;
}
.compact {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  padding-top: 0;
  background: var(--line);
}
.metric {
  min-height: 132px;
  padding: 28px;
  background: #fff;
}
.metric strong,
.metric span { display: block; }
.metric strong { font-size: 24px; }
.metric span { color: var(--muted); }
.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(28px, 6vw, 68px);
  align-items: start;
}
.stack {
  display: grid;
  gap: 18px;
}
.stack article,
.cards article,
details {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}
.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}
.proof { background: var(--surface); }
.proof-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}
.proof-grid p {
  min-height: 150px;
  padding: 24px;
  border-left: 4px solid var(--accent);
  background: #fff;
}
.faq {
  display: grid;
  gap: 14px;
}
summary {
  cursor: pointer;
  font-weight: 800;
}
.page-title {
  background: var(--surface);
}
.signal-list {
  display: grid;
  gap: 16px;
}
.signal-list p {
  margin: 0;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.signal-list p:last-child { border-bottom: 0; padding-bottom: 0; }
.signal-list span { display: block; color: var(--muted); }
.timeline ol {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: steps;
}
.timeline li {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 18px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
}
.timeline li::before {
  counter-increment: steps;
  content: counter(steps);
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  color: #fff;
  background: var(--accent);
  font-weight: 800;
}
.timeline strong,
.timeline span { display: block; }
.timeline span { color: var(--muted); }
.site-footer {
  border-top: 1px solid var(--line);
  background: #fff;
}
.footer-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.site-footer p {
  max-width: 720px;
  margin: 8px 0 0;
  color: var(--muted);
}
.site-credit {
  max-width: none;
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 14px;
}
.site-credit a {
  color: var(--accent-strong);
  font-weight: 800;
  text-decoration: none;
}

@media (max-width: 820px) {
  .site-header { position: static; align-items: flex-start; flex-direction: column; }
  nav { justify-content: flex-start; }
  .hero,
  .split,
  .compact,
  .cards,
  .proof-grid {
    grid-template-columns: 1fr;
  }
  .hero { min-height: auto; }
  .hero-media { aspect-ratio: 4 / 3; }
  .footer-main { align-items: flex-start; flex-direction: column; }
  .timeline li { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  h1 {
    font-size: 34px;
    line-height: 1.14;
  }
}