:root {
  --ink: #050911;
  --graphite: #0f1520;
  --steel: #5e6a7c;
  --silver: #9aa4b2;
  --mist: #eef1f5;
  --snow: #ffffff;
  --signal: #1d5af5;
  --data: #00b4d8;
  --run: #10b981;
  --line: rgba(15, 21, 32, 0.08);
  --line-dark: rgba(255, 255, 255, 0.12);
  --radius-sm: 8px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --shadow-sm: 0 1px 2px rgba(5, 9, 17, 0.04);
  --shadow-md: 0 14px 38px rgba(5, 9, 17, 0.09);
  --signal-soft: #2c6bff;
  --font-display: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: #fff;
  color: var(--graphite);
  font-family: var(--font-display);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

.wrap {
  width: min(1200px, calc(100% - 48px));
  margin: 0 auto;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  border-bottom: 1px solid transparent;
  transition: background 300ms ease, border-color 300ms ease;
}

.site-header.scrolled,
.site-header.is-light {
  border-bottom-color: var(--line);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
}

.header-inner {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: #fff;
  transition: color 300ms ease;
}

.site-header.scrolled .brand,
.site-header.is-light .brand {
  color: var(--graphite);
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.desktop-nav a {
  color: rgba(255, 255, 255, 0.72);
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  transition: color 200ms ease;
}

.desktop-nav a:hover,
.desktop-nav a.active { color: #fff; }

.site-header.scrolled .desktop-nav a,
.site-header.is-light .desktop-nav a {
  color: var(--graphite);
}

.site-header.scrolled .desktop-nav a:hover,
.site-header.scrolled .desktop-nav a.active,
.site-header.is-light .desktop-nav a:hover,
.site-header.is-light .desktop-nav a.active {
  color: var(--signal);
}

.header-actions {
  display: flex;
  gap: 12px;
  align-items: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  border-radius: var(--radius-sm);
  padding: 0 20px;
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 600;
  transition: transform 220ms cubic-bezier(0.34, 1.8, 0.64, 1), box-shadow 220ms ease, background 220ms ease, border-color 220ms ease;
}

.btn:hover { transform: translateY(-2px); }

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.18);
  color: #fff;
}

.site-header.scrolled .btn-secondary,
.site-header.is-light .btn-secondary {
  border-color: var(--line);
  background: var(--snow);
  color: var(--graphite);
}

.btn-primary {
  background: var(--signal);
  border-color: var(--signal);
  color: #fff;
  box-shadow: 0 18px 36px rgba(29, 90, 245, 0.20);
}

.btn-primary:hover {
  background: var(--signal-soft);
  box-shadow: 0 16px 36px rgba(29, 90, 245, 0.34);
}

.menu-button {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line-dark);
  background: rgba(255, 255, 255, 0.06);
  color: #fff;
  border-radius: var(--radius-sm);
  align-items: center;
  justify-content: center;
  cursor: pointer;
  position: relative;
  transition: color 300ms ease, border-color 300ms ease, background 300ms ease;
}

.site-header.scrolled .menu-button,
.site-header.is-light .menu-button {
  color: var(--graphite);
  border-color: var(--line);
  background: var(--snow);
}

.menu-button span,
.menu-button::before,
.menu-button::after {
  content: "";
  display: block;
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
  position: absolute;
  transition: transform 200ms ease;
}

.menu-button::before { transform: translateY(-6px); }
.menu-button::after { transform: translateY(6px); }

.mobile-drawer {
  display: none;
  border-top: 1px solid var(--line-dark);
  padding: 12px 0 18px;
}

.mobile-drawer a {
  display: block;
  color: rgba(255, 255, 255, 0.78);
  padding: 12px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  font-size: 15px;
}

.site-header.scrolled .mobile-drawer,
.site-header.is-light .mobile-drawer {
  border-top-color: var(--line);
}

.site-header.scrolled .mobile-drawer a,
.site-header.is-light .mobile-drawer a {
  color: var(--graphite);
  border-bottom-color: var(--line);
}

.mobile-drawer.open { display: block; }

.hero {
  position: relative;
  overflow: hidden;
  padding: 148px 0 78px;
  background:
    radial-gradient(circle at 78% 18%, rgba(0, 180, 216, 0.18), transparent 32%),
    linear-gradient(145deg, #071120 0%, #0c1624 62%, #0f1520 100%);
  color: #fff;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 54px 54px;
  opacity: 0.62;
}

.hero-layout {
  position: relative;
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 46px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
  color: var(--data);
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 28px;
  height: 2px;
  background: currentColor;
}

h1 {
  margin: 0;
  font-size: clamp(42px, 5vw, 72px);
  line-height: 0.98;
  letter-spacing: 0;
}

.hero p {
  margin: 22px 0 0;
  max-width: 620px;
  color: rgba(255, 255, 255, 0.66);
  font-size: 17px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-bottom: 18px;
  color: rgba(255, 255, 255, 0.58);
  font-size: 13px;
}

.breadcrumb a:hover { color: #fff; }

.breadcrumb span:not(:last-child)::after {
  content: "/";
  margin-left: 8px;
  color: rgba(255, 255, 255, 0.32);
}

.case-meta {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 28px;
  max-width: 680px;
}

.case-meta span {
  display: grid;
  gap: 4px;
  min-height: 74px;
  padding: 13px 14px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.06);
  color: rgba(255, 255, 255, 0.58);
  font-size: 12px;
}

.case-meta b {
  color: #fff;
  font-size: 14px;
}

.hero-media {
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 26px;
  background: rgba(255, 255, 255, 0.06);
  padding: 14px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.28);
}

.hero-media img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border-radius: 18px;
}

.section {
  padding: 76px 0;
}

.section.mist { background: var(--mist); }

.section-head {
  display: flex;
  justify-content: space-between;
  gap: 32px;
  align-items: end;
  margin-bottom: 28px;
}

.section-head h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.06;
}

.section-head p {
  max-width: 520px;
  margin: 0;
  color: var(--steel);
}

.chip {
  display: inline-flex;
  width: fit-content;
  border-radius: 999px;
  padding: 5px 10px;
  background: rgba(29, 90, 245, 0.08);
  color: var(--signal);
  font-size: 12px;
  font-weight: 800;
}

.summary-grid,
.evidence-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.summary-card,
.evidence-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: #fff;
  padding: 22px;
  box-shadow: var(--shadow-sm);
}

.summary-card b,
.evidence-card b {
  display: block;
  margin: 12px 0 8px;
  font-size: 20px;
}

.summary-card p,
.evidence-card p {
  margin: 0;
  color: var(--steel);
}

.story-grid {
  display: grid;
  grid-template-columns: 0.92fr 1.08fr;
  gap: 18px;
}

.story-panel,
.result-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: #fff;
  padding: 26px;
  box-shadow: var(--shadow-sm);
}

.story-panel.dark {
  background:
    radial-gradient(circle at 86% 8%, rgba(0, 180, 216, 0.13), transparent 32%),
    linear-gradient(145deg, #071120, #101826);
  color: #fff;
}

.story-panel h3,
.result-card h3 {
  margin: 0 0 12px;
  font-size: 22px;
}

.story-panel p,
.result-card p {
  margin: 0;
  color: var(--steel);
}

.story-panel.dark p {
  color: rgba(255, 255, 255, 0.66);
}

.story-list {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
  display: grid;
  gap: 10px;
}

.story-list li {
  display: grid;
  grid-template-columns: 10px 1fr;
  gap: 10px;
  color: inherit;
}

.story-list li::before {
  content: "";
  width: 7px;
  height: 7px;
  margin-top: 10px;
  border-radius: 999px;
  background: var(--data);
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.result-card b {
  display: block;
  margin-bottom: 8px;
  color: var(--signal);
  font-size: 13px;
}

.case-cta {
  border-radius: 28px;
  padding: 34px;
  background:
    radial-gradient(circle at 84% 10%, rgba(0, 180, 216, 0.18), transparent 36%),
    linear-gradient(135deg, #071120, #101826);
  color: #fff;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
}

.case-cta h2 {
  margin: 0 0 10px;
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.1;
}

.case-cta p {
  max-width: 680px;
  margin: 0;
  color: rgba(255, 255, 255, 0.64);
}

.process-list {
  display: grid;
  gap: 14px;
}

.process-item {
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: #fff;
  padding: 22px;
  box-shadow: var(--shadow-sm);
}

.process-item span {
  color: var(--data);
  font-weight: 900;
}

.process-item h3 {
  margin: 0 0 8px;
  font-size: 20px;
}

.process-item p {
  margin: 0;
  color: var(--steel);
}

.footer {
  background: #050911;
  color: rgba(255, 255, 255, 0.62);
  padding: 42px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: center;
}

@media (max-width: 900px) {
  .hero-layout,
  .summary-grid,
  .evidence-grid,
  .story-grid,
  .result-grid {
    grid-template-columns: 1fr;
  }

  .desktop-nav,
  .header-actions .btn-secondary { display: none; }
  .menu-button { display: inline-flex; }
  .case-meta { grid-template-columns: 1fr; }
  .case-cta { display: block; }
  .case-cta .btn { margin-top: 20px; }
  .section-head { display: block; }
  .section-head p { margin-top: 12px; }
}

@media (max-width: 640px) {
  .wrap { width: min(100% - 32px, 1200px); }
  .hero { padding: 118px 0 52px; }
  .process-item { grid-template-columns: 1fr; }
  .footer-inner { display: block; }
}