:root {
  color-scheme: light;
  --ink: #102033;
  --muted: #5c6f84;
  --line: #d9e5f1;
  --surface: #ffffff;
  --soft: #eef7ff;
  --blue: #2563eb;
  --blue-strong: #164ec4;
  --teal: #10b981;
  --yellow: #f4c430;
  --shadow: 0 18px 55px rgba(30, 85, 145, 0.15);
  font-family: "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: #f8fbff;
  line-height: 1.65;
}

a {
  color: inherit;
}

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(18px, 5vw, 72px);
  color: #ffffff;
  transition: background 180ms ease, color 180ms ease, border-color 180ms ease;
}

.site-header.scrolled,
.site-header.solid {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(217, 229, 241, 0.9);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 8px;
  color: #ffffff;
  background: linear-gradient(135deg, var(--blue), var(--teal));
  font-weight: 800;
}

.brand strong,
.brand small {
  display: block;
  line-height: 1.15;
}

.brand small {
  margin-top: 3px;
  color: currentColor;
  opacity: 0.72;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2.5vw, 28px);
  font-size: 15px;
}

.site-nav a {
  text-decoration: none;
  opacity: 0.88;
}

.site-nav a:hover {
  opacity: 1;
}

.hero {
  position: relative;
  min-height: 760px;
  display: grid;
  align-items: center;
  overflow: hidden;
  padding: 120px clamp(20px, 7vw, 96px) 88px;
}

.hero-image,
.hero-scrim {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-image {
  object-fit: cover;
}

.hero-scrim {
  background:
    linear-gradient(90deg, rgba(9, 32, 62, 0.80) 0%, rgba(9, 32, 62, 0.62) 38%, rgba(9, 32, 62, 0.18) 72%, rgba(9, 32, 62, 0.06) 100%),
    linear-gradient(180deg, rgba(9, 32, 62, 0.28), rgba(9, 32, 62, 0.06));
}

.hero-content {
  position: relative;
  max-width: 710px;
  color: #ffffff;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #9ed8ff;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 18px;
  font-size: clamp(52px, 8vw, 92px);
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.16;
}

h3 {
  font-size: 24px;
  line-height: 1.24;
}

.hero-copy {
  max-width: 620px;
  margin-bottom: 30px;
  color: rgba(255, 255, 255, 0.88);
  font-size: clamp(18px, 2vw, 23px);
}

.hero-actions,
.app-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  padding: 0 18px;
  font-weight: 800;
  text-decoration: none;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button.primary {
  color: #ffffff;
  background: var(--blue);
}

.button.primary:hover {
  background: var(--blue-strong);
}

.button.secondary {
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.72);
  background: rgba(255, 255, 255, 0.08);
}

.text-link {
  color: var(--blue);
  font-weight: 800;
  text-decoration: none;
}

.trust-band {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
}

.metric {
  padding: 28px clamp(20px, 5vw, 72px);
  background: #ffffff;
}

.metric strong,
.metric span {
  display: block;
}

.metric strong {
  font-size: 22px;
}

.metric span {
  margin-top: 4px;
  color: var(--muted);
}

.section {
  padding: 92px clamp(20px, 6vw, 96px);
}

.section.alt {
  background: #ffffff;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 42px;
}

.section-heading p:not(.eyebrow) {
  color: var(--muted);
  font-size: 18px;
}

.app-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 430px);
  gap: clamp(28px, 6vw, 72px);
  align-items: center;
  max-width: 1180px;
}

.app-copy {
  max-width: 620px;
}

.status-pill {
  display: inline-flex;
  margin-bottom: 16px;
  border-radius: 999px;
  padding: 6px 12px;
  color: #075985;
  background: #dff4ff;
  font-size: 13px;
  font-weight: 800;
}

.feature-list {
  display: grid;
  gap: 10px;
  margin: 24px 0 28px;
  padding: 0;
  list-style: none;
}

.feature-list li {
  position: relative;
  padding-left: 24px;
}

.feature-list li::before {
  position: absolute;
  top: 0.72em;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: var(--teal);
  content: "";
}

.app-shot {
  margin: 0;
}

.app-shot img {
  width: min(100%, 380px);
  margin-inline: auto;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.principle-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  max-width: 1120px;
}

.principle-grid article,
.support-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 24px;
  background: #ffffff;
}

.principle-grid p,
.doc p,
.support-panel p {
  color: var(--muted);
}

.contact-band {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 70px clamp(20px, 6vw, 96px);
  color: #ffffff;
  background: linear-gradient(135deg, #0e6ac7, #0ea885);
}

.contact-band h2,
.contact-band p {
  max-width: 720px;
}

.contact-band p:not(.eyebrow) {
  color: rgba(255, 255, 255, 0.84);
}

.contact-band .eyebrow {
  color: #c8f3ff;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 22px;
  padding: 28px clamp(20px, 6vw, 96px);
  color: var(--muted);
  background: #ffffff;
  border-top: 1px solid var(--line);
}

.site-footer a {
  color: var(--ink);
  text-decoration: none;
}

.subpage {
  padding-top: 82px;
}

.doc {
  max-width: 900px;
  margin-inline: auto;
  padding: 72px 22px 96px;
}

.doc h1 {
  color: var(--ink);
  font-size: clamp(42px, 6vw, 68px);
}

.doc h2 {
  margin-top: 38px;
  font-size: 28px;
}

.lead {
  font-size: 19px;
}

.support-panel + .support-panel {
  margin-top: 18px;
}

.not-found {
  min-height: 72vh;
}

@media (max-width: 820px) {
  .site-header {
    align-items: flex-start;
    padding: 14px 18px;
  }

  .site-nav {
    gap: 10px;
    font-size: 13px;
  }

  .brand small {
    display: none;
  }

  .hero {
    min-height: 720px;
    padding-top: 110px;
  }

  .hero-scrim {
    background: linear-gradient(180deg, rgba(9, 32, 62, 0.78), rgba(9, 32, 62, 0.38));
  }

  .trust-band,
  .app-card,
  .principle-grid {
    grid-template-columns: 1fr;
  }

  .metric {
    padding: 22px;
  }

  .section {
    padding: 68px 20px;
  }

  .contact-band {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 540px) {
  .site-header {
    position: absolute;
  }

  .site-nav {
    display: none;
  }

  .hero {
    min-height: 680px;
  }

  h1 {
    font-size: 52px;
  }
}