:root {
  --blue: #176eb2;
  --blue-dark: #0d416d;
  --ink: #142233;
  --muted: #5e6d7c;
  --line: #dce6ef;
  --paper: #ffffff;
  --wash: #f4f8fb;
  --green: #2bbf8f;
  --gold: #d6a84f;
  --shadow: 0 18px 48px rgba(20, 34, 51, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
}

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

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

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  padding: 0 clamp(20px, 5vw, 72px);
  color: #fff;
  transition: background 180ms ease, box-shadow 180ms ease, color 180ms ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 10px 28px rgba(20, 34, 51, 0.08);
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  width: min(280px, 58vw);
  min-height: 48px;
}

.brand img {
  height: 42px;
  width: auto;
  object-fit: contain;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 32px;
  font-size: 15px;
  font-weight: 600;
}

.site-nav a {
  position: relative;
  padding: 8px 0;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 2px;
  left: 0;
  height: 2px;
  content: "";
  background: var(--green);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.site-nav a:hover::after,
.site-nav a.is-active::after {
  transform: scaleX(1);
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid currentColor;
  border-radius: 8px;
  color: inherit;
  background: transparent;
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 92vh;
  overflow: hidden;
  display: grid;
  align-items: center;
  padding: 120px clamp(20px, 5vw, 72px) 72px;
  color: #fff;
}

.hero-media {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(8, 24, 39, 0.86) 0%, rgba(8, 24, 39, 0.72) 37%, rgba(8, 24, 39, 0.24) 73%, rgba(8, 24, 39, 0.08) 100%),
    linear-gradient(0deg, rgba(8, 24, 39, 0.42), rgba(8, 24, 39, 0.04));
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(720px, 100%);
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--green);
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  font-size: clamp(58px, 8vw, 120px);
  line-height: 1;
  letter-spacing: 0;
}

.hero-subtitle {
  width: min(650px, 100%);
  margin: 28px 0 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: clamp(18px, 2.2vw, 26px);
  line-height: 1.75;
}

.hero-actions,
.contact-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 700;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

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

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

.button.secondary {
  color: #fff;
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.48);
}

.button.light {
  color: #fff;
  background: transparent;
}

.section,
.section-band {
  padding: clamp(72px, 9vw, 116px) clamp(20px, 5vw, 72px);
}

.section-band {
  background: var(--wash);
}

.section-inner {
  width: min(1160px, 100%);
  margin: 0 auto;
}

.intro-grid,
.system-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(320px, 1.12fr);
  gap: clamp(32px, 7vw, 88px);
  align-items: center;
}

h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(32px, 4.5vw, 54px);
  line-height: 1.18;
  letter-spacing: 0;
}

h3 {
  margin: 0;
  font-size: 25px;
  line-height: 1.3;
  letter-spacing: 0;
}

p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.85;
}

.intro-grid p {
  margin: 0;
}

.section-heading {
  width: min(780px, 100%);
  margin-bottom: 36px;
}

.section-heading p:last-child {
  margin-bottom: 0;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.product-card,
.scenario-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 10px 28px rgba(20, 34, 51, 0.05);
}

.product-card {
  min-height: 420px;
  padding: clamp(28px, 4vw, 42px);
}

.product-index {
  margin-bottom: 34px;
  color: var(--blue);
  font-size: 48px;
  font-weight: 900;
  line-height: 1;
}

.product-card p {
  margin: 18px 0 24px;
}

.product-card ul {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.product-card li {
  position: relative;
  padding-left: 22px;
  color: var(--ink);
  font-weight: 700;
}

.product-card li::before {
  position: absolute;
  top: 0.66em;
  left: 0;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  content: "";
  background: var(--green);
}

.system-grid p {
  margin-bottom: 0;
}

.flow {
  display: grid;
  grid-template-columns: 1fr 40px 1fr 40px 1fr;
  align-items: center;
  gap: 8px;
}

.flow-step {
  min-height: 136px;
  padding: 24px 18px;
  border: 1px solid rgba(23, 110, 178, 0.22);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}

.flow-step strong,
.flow-step span {
  display: block;
  text-align: center;
}

.flow-step strong {
  color: var(--blue-dark);
  font-size: 20px;
}

.flow-step span {
  margin-top: 12px;
  color: var(--muted);
}

.flow-arrow {
  height: 2px;
  background: linear-gradient(90deg, var(--blue), var(--green));
}

.flow-arrow::after {
  display: block;
  width: 8px;
  height: 8px;
  margin-top: -3px;
  margin-left: auto;
  content: "";
  border-top: 2px solid var(--green);
  border-right: 2px solid var(--green);
  transform: rotate(45deg);
}

.scenario-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.scenario-card {
  min-height: 260px;
  padding: 26px;
}

.scenario-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  margin-bottom: 30px;
  border-radius: 8px;
  color: #fff;
  background: var(--blue-dark);
  font-weight: 800;
}

.scenario-card h3 {
  font-size: 21px;
}

.scenario-card p {
  margin-bottom: 0;
  font-size: 15px;
}

.advantages {
  background: linear-gradient(180deg, #fff 0%, #f8fbfd 100%);
}

.advantage-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.advantage-list div {
  min-height: 210px;
  padding: 28px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72);
}

.advantage-list strong {
  display: block;
  color: var(--blue-dark);
  font-size: 22px;
}

.advantage-list p {
  margin-bottom: 0;
  font-size: 15px;
}

.contact {
  padding: clamp(72px, 9vw, 116px) clamp(20px, 5vw, 72px);
  color: #fff;
  background: #123047;
}

.contact-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 28px;
  align-items: center;
  padding: clamp(32px, 5vw, 56px);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(23, 110, 178, 0.72), rgba(43, 191, 143, 0.18)),
    #123047;
}

.contact h2,
.contact p {
  color: #fff;
}

.contact p {
  width: min(680px, 100%);
  margin-bottom: 0;
  color: rgba(255, 255, 255, 0.82);
}

.contact-info a {
  color: #fff;
  font-weight: 700;
}

.contact-actions {
  margin: 0;
  justify-content: flex-end;
}

.site-footer {
  padding: 28px clamp(20px, 5vw, 72px);
  background: #091925;
  color: rgba(255, 255, 255, 0.76);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1160px, 100%);
  gap: 24px;
  margin: 0 auto;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 14px;
}

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 8px;
  object-fit: cover;
}

.footer-brand strong,
.footer-brand span {
  display: block;
}

.footer-brand strong {
  color: #fff;
  font-size: 18px;
}

.footer-brand span,
.footer-links {
  font-size: 13px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 18px;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.76);
}

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 540ms ease, transform 540ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 980px) {
  .site-nav {
    position: fixed;
    top: 76px;
    right: 16px;
    left: 16px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--ink);
    background: #fff;
    box-shadow: var(--shadow);
  }

  .site-nav.is-open {
    display: flex;
  }

  .site-nav a {
    padding: 14px 12px;
  }

  .menu-toggle {
    display: block;
  }

  .intro-grid,
  .system-grid,
  .contact-panel {
    grid-template-columns: 1fr;
  }

  .product-grid,
  .scenario-grid,
  .advantage-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .contact-actions {
    justify-content: flex-start;
  }
}

@media (max-width: 700px) {
  .site-header {
    height: 68px;
  }

  .brand img {
    height: 34px;
  }

  .site-nav {
    top: 68px;
  }

  .hero {
    min-height: 86vh;
    padding-top: 112px;
  }

  .hero-shade {
    background: linear-gradient(90deg, rgba(8, 24, 39, 0.9), rgba(8, 24, 39, 0.58));
  }

  .hero-actions,
  .contact-actions {
    width: 100%;
  }

  .button {
    width: 100%;
  }

  .product-grid,
  .scenario-grid,
  .advantage-list {
    grid-template-columns: 1fr;
  }

  .product-card,
  .scenario-card,
  .advantage-list div {
    min-height: auto;
  }

  .flow {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .flow-arrow {
    width: 2px;
    height: 34px;
    margin: 0 auto;
    background: linear-gradient(180deg, var(--blue), var(--green));
  }

  .flow-arrow::after {
    margin-top: auto;
    margin-left: -3px;
    transform: rotate(135deg);
  }

  .footer-inner,
  .footer-links {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}