:root {
  --ink: #102033;
  --muted: #5f6f7d;
  --line: #e4e9ed;
  --paper: #ffffff;
  --soft: #f3f7f5;
  --green: #16795f;
  --green-dark: #0f4f42;
  --amber: #e9a72f;
  --coral: #cf6544;
  --cyan: #dff3f1;
  --shadow: 0 18px 50px rgba(17, 34, 51, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

body.nav-open {
  overflow: hidden;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  padding: 0 clamp(20px, 5vw, 72px);
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(16, 32, 51, 0.08);
  backdrop-filter: blur(12px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand-mark {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  overflow: hidden;
  background: #fff9df;
  border: 1px solid rgba(233, 167, 47, 0.32);
  border-radius: 8px;
}

.brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.brand strong,
.brand small {
  display: block;
  white-space: nowrap;
}

.brand strong {
  font-size: 18px;
}

.brand small {
  margin-top: 2px;
  color: var(--muted);
  font-size: 12px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(18px, 3vw, 36px);
  color: #2d3d4d;
  font-size: 15px;
}

.site-nav a {
  position: relative;
  padding: 25px 0;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 18px;
  left: 0;
  height: 2px;
  background: var(--green);
  content: "";
  opacity: 0;
  transform: scaleX(0.4);
  transition: 0.2s ease;
}

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

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.nav-toggle span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
}

.hero {
  position: relative;
  display: grid;
  min-height: clamp(480px, 72svh, 660px);
  align-items: center;
  overflow: hidden;
  color: #fff;
  isolation: isolate;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -2;
  background-image: url("https://images.unsplash.com/photo-1586528116311-ad8dd3c8310d?auto=format&fit=crop&w=1800&q=82");
  background-position: center;
  background-size: cover;
}

.hero::before {
  position: absolute;
  inset: 0;
  z-index: -1;
  background: rgba(10, 24, 32, 0.56);
  content: "";
}

.hero-content {
  width: min(980px, calc(100% - 40px));
  margin: 0 auto;
  padding: 46px 0;
}

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

.hero .eyebrow {
  color: var(--amber);
}

.hero h1 {
  margin: 0;
  font-size: 78px;
  line-height: 1.02;
  letter-spacing: 0;
}

.hero-copy {
  width: min(720px, 100%);
  margin: 22px 0 0;
  color: rgba(255, 255, 255, 0.88);
  font-size: 21px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.btn {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 6px;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

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

.btn.primary {
  color: #fff;
  background: var(--green);
}

.btn.primary:hover {
  background: var(--green-dark);
}

.btn.ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.7);
  background: rgba(255, 255, 255, 0.08);
}

.quick-stats {
  position: relative;
  z-index: 1;
  display: grid;
  width: min(1120px, calc(100% - 40px));
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin: 30px auto 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--line);
  box-shadow: var(--shadow);
}

.quick-stats div {
  padding: 24px 22px;
  background: #fff;
}

.quick-stats strong {
  display: block;
  color: var(--green);
  font-size: 34px;
  line-height: 1;
}

.quick-stats span {
  display: block;
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
}

.section {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: clamp(72px, 10vw, 112px) 0;
}

.section-head {
  width: min(760px, 100%);
  margin: 0 auto 42px;
  text-align: center;
}

.section-head.align-left {
  margin-right: 0;
  margin-left: 0;
  text-align: left;
}

.section h2 {
  margin: 0;
  font-size: 44px;
  line-height: 1.18;
  letter-spacing: 0;
}

.section-head p:not(.eyebrow),
.network-copy p,
.about-copy p,
.contact-copy p {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.9;
}

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

.service-card {
  min-height: 240px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.service-card:nth-child(2) {
  border-top-color: var(--amber);
}

.service-card:nth-child(3) {
  border-top-color: var(--coral);
}

.service-card:nth-child(4) {
  border-top-color: #43a7a1;
}

.card-icon {
  display: inline-block;
  color: var(--green);
  font-weight: 800;
}

.service-card h3,
.solution-item h3 {
  margin: 24px 0 12px;
  font-size: 21px;
}

.service-card p,
.solution-item p {
  margin: 0;
  color: var(--muted);
  line-height: 1.8;
}

.feature-band {
  width: 100%;
  padding-right: max(20px, calc((100% - 1120px) / 2));
  padding-left: max(20px, calc((100% - 1120px) / 2));
  background: var(--soft);
}

.solution-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.solution-item {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.solution-item img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.solution-item div {
  padding: 24px;
}

.solution-item span {
  color: var(--coral);
  font-size: 13px;
  font-weight: 800;
}

.network {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: clamp(30px, 6vw, 70px);
  align-items: center;
}

.network-steps {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.network-steps div {
  min-height: 150px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(145deg, #ffffff 0%, #f9fcfb 100%);
}

.network-steps strong {
  display: block;
  font-size: 24px;
}

.network-steps span {
  display: block;
  margin-top: 12px;
  color: var(--muted);
}

.network-steps div:nth-child(2) strong {
  color: var(--amber);
}

.network-steps div:nth-child(3) strong {
  color: var(--coral);
}

.network-steps div:nth-child(4) strong {
  color: var(--green);
}

.about {
  display: grid;
  grid-template-columns: 1fr 0.9fr;
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
}

.about-media {
  overflow: hidden;
  border-radius: 8px;
}

.about-media img {
  width: 100%;
  min-height: 420px;
  object-fit: cover;
}

.check-list {
  display: grid;
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding-left: 28px;
  color: #2a3b4c;
}

.check-list li::before {
  position: absolute;
  top: 2px;
  left: 0;
  color: var(--green);
  content: "✓";
  font-weight: 800;
}

.contact {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: clamp(28px, 6vw, 72px);
  align-items: start;
  border-top: 1px solid var(--line);
}

.contact-form {
  display: grid;
  gap: 16px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 14px 36px rgba(16, 32, 51, 0.08);
}

.contact-form label {
  display: grid;
  gap: 8px;
}

.contact-form span {
  color: #2b3d4d;
  font-weight: 700;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  border: 1px solid #d8e0e5;
  border-radius: 6px;
  padding: 13px 14px;
  color: var(--ink);
  font: inherit;
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: var(--green);
  box-shadow: 0 0 0 3px rgba(22, 121, 95, 0.12);
}

.form-note {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.form-note.success {
  color: var(--green);
}

.site-footer {
  display: flex;
  min-height: 110px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 26px clamp(20px, 5vw, 72px);
  color: rgba(255, 255, 255, 0.76);
  background: #15251f;
}

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

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

.site-footer span {
  margin-top: 8px;
  font-size: 14px;
}

.site-footer a:hover {
  color: #fff;
}

@media (max-width: 920px) {
  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: 72px;
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px 20px 24px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
  }

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

  .site-nav a {
    padding: 16px 0;
    border-bottom: 1px solid var(--line);
  }

  .site-nav a::after {
    display: none;
  }

  .quick-stats,
  .service-grid,
  .solution-list,
  .network,
  .about,
  .contact {
    grid-template-columns: 1fr 1fr;
  }

  .network-copy,
  .contact-copy {
    grid-column: 1 / -1;
  }

  .hero h1 {
    font-size: 60px;
  }

  .section h2 {
    font-size: 36px;
  }
}

@media (max-width: 640px) {
  .site-header {
    height: 64px;
    padding: 0 16px;
  }

  .brand-mark {
    width: 40px;
    height: 40px;
  }

  .brand small {
    display: none;
  }

  .site-nav {
    top: 64px;
  }

  .hero {
    min-height: 70svh;
  }

  .hero h1 {
    font-size: 44px;
  }

  .hero-copy {
    font-size: 17px;
  }

  .quick-stats strong {
    font-size: 28px;
  }

  .section h2 {
    font-size: 30px;
  }

  .hero-content,
  .section,
  .quick-stats {
    width: calc(100% - 28px);
  }

  .quick-stats,
  .service-grid,
  .solution-list,
  .network,
  .network-steps,
  .about,
  .contact {
    grid-template-columns: 1fr;
  }

  .quick-stats {
    margin-top: 20px;
  }

  .quick-stats div {
    padding: 18px;
  }

  .service-card {
    min-height: auto;
  }

  .about-media img {
    min-height: 280px;
  }

  .contact-form {
    padding: 20px;
  }

  .site-footer {
    display: grid;
    justify-items: start;
  }
}