:root {
  --ink: #101820;
  --ink-soft: #35414a;
  --muted: #6f7c86;
  --line: #dfe8ea;
  --paper: #f7faf9;
  --white: #ffffff;
  --teal: #0e8f8f;
  --teal-dark: #075f66;
  --amber: #d79a2b;
  --coral: #c85d4b;
  --shadow: 0 18px 45px rgba(16, 24, 32, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family:
    Inter, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", Arial,
    sans-serif;
  line-height: 1.6;
}

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

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 20;
  width: 100%;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(20px, 5vw, 72px);
  color: var(--white);
  background: rgba(9, 18, 23, 0.3);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  transition:
    background 180ms ease,
    color 180ms ease,
    box-shadow 180ms ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 8px 26px rgba(16, 24, 32, 0.08);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  letter-spacing: 0;
}

.brand-logo {
  width: 42px;
  height: 42px;
  object-fit: contain;
  border-radius: 8px;
  background: var(--white);
}

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

.site-nav {
  display: flex;
  align-items: center;
  gap: 30px;
  font-size: 15px;
  font-weight: 650;
}

.site-nav a {
  opacity: 0.86;
}

.site-nav a:hover {
  opacity: 1;
  color: var(--amber);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 0;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.12);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  margin: 5px 0;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 620px;
  height: min(82svh, 760px);
  overflow: hidden;
  color: var(--white);
  background: #0b151a;
}

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

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

.hero-shade {
  background:
    linear-gradient(90deg, rgba(6, 15, 19, 0.93), rgba(6, 15, 19, 0.58) 43%, rgba(6, 15, 19, 0.16)),
    linear-gradient(0deg, rgba(6, 15, 19, 0.28), rgba(6, 15, 19, 0.05));
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(1120px, calc(100% - 40px));
  height: 100%;
  margin: 0 auto;
  padding-top: 72px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--amber);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  max-width: 720px;
  font-size: clamp(54px, 8vw, 108px);
  line-height: 0.96;
  letter-spacing: 0;
}

.hero-lede {
  width: min(650px, 100%);
  margin: 26px 0 0;
  color: rgba(255, 255, 255, 0.86);
  font-size: clamp(18px, 2.2vw, 25px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 38px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 8px;
  border: 1px solid transparent;
  font-weight: 750;
  transition:
    transform 160ms ease,
    background 160ms ease,
    border 160ms ease;
}

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

.button.primary {
  color: var(--white);
  background: var(--teal);
}

.button.primary:hover {
  background: var(--teal-dark);
}

.button.secondary {
  color: var(--white);
  border-color: rgba(255, 255, 255, 0.58);
  background: rgba(255, 255, 255, 0.08);
}

.intro {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 520px);
  gap: 42px;
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 72px 0;
  align-items: center;
}

.intro h2,
.section-heading h2,
.platform-copy h2,
.contact-copy h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 50px);
  line-height: 1.12;
  letter-spacing: 0;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  overflow: hidden;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--line);
  box-shadow: var(--shadow);
}

.metrics div {
  min-height: 132px;
  padding: 22px;
  background: var(--white);
}

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

.metrics strong {
  color: var(--teal-dark);
  font-size: clamp(26px, 3vw, 38px);
  line-height: 1;
}

.metrics span {
  margin-top: 14px;
  color: var(--muted);
  font-size: 14px;
}

.section {
  padding: 84px max(20px, calc((100vw - 1120px) / 2));
}

.band {
  background: var(--white);
}

.section-heading {
  max-width: 740px;
  margin-bottom: 34px;
}

.section-heading p:last-child,
.platform-copy p,
.contact-copy p {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.service-card {
  min-height: 310px;
  padding: 28px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fbfdfc;
  transition:
    transform 180ms ease,
    box-shadow 180ms ease,
    border 180ms ease;
}

.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(14, 143, 143, 0.35);
  box-shadow: var(--shadow);
}

.card-index {
  color: var(--coral);
  font-weight: 850;
}

.service-card h3,
.capability h3,
.steps h3 {
  margin: 18px 0 10px;
  font-size: 22px;
  line-height: 1.25;
}

.service-card p,
.capability p,
.steps p {
  margin: 0;
  color: var(--muted);
}

.platform {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.1fr);
  gap: 58px;
  align-items: start;
  background: #102027;
  color: var(--white);
}

.platform-copy {
  position: sticky;
  top: 110px;
}

.platform-copy p {
  color: rgba(255, 255, 255, 0.72);
}

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

.capability {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 18px;
  padding: 24px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
}

.capability span {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background:
    radial-gradient(circle at 35% 35%, var(--white) 0 10%, transparent 11%),
    linear-gradient(135deg, var(--teal), var(--amber));
}

.capability h3 {
  margin-top: 0;
}

.capability p {
  color: rgba(255, 255, 255, 0.7);
}

.workflow {
  background: var(--paper);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  padding: 0;
  margin: 0;
  list-style: none;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--line);
}

.steps li {
  min-height: 245px;
  padding: 26px;
  background: var(--white);
}

.steps span {
  color: var(--teal);
  font-weight: 850;
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(320px, 520px);
  gap: 52px;
  padding: 84px max(20px, calc((100vw - 1120px) / 2));
  background: var(--white);
}

.contact-methods {
  display: grid;
  gap: 10px;
  margin-top: 28px;
  color: var(--teal-dark);
  font-weight: 750;
}

.wechat-card {
  display: inline-grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 18px;
  align-items: center;
  max-width: 410px;
  margin-top: 28px;
  padding: 16px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.wechat-card img {
  width: 120px;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 6px;
  background: var(--white);
}

.wechat-card strong,
.wechat-card span {
  display: block;
}

.wechat-card strong {
  color: var(--ink);
  font-size: 18px;
}

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

.contact-form {
  display: grid;
  gap: 16px;
  padding: 28px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.contact-form label {
  display: grid;
  gap: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  font-weight: 750;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  border: 1px solid #cdd8db;
  border-radius: 8px;
  padding: 13px 14px;
  color: var(--ink);
  background: var(--white);
  font: inherit;
  resize: vertical;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: 3px solid rgba(14, 143, 143, 0.18);
  border-color: var(--teal);
}

.form-button {
  width: 100%;
  border: 0;
  cursor: pointer;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 28px clamp(20px, 5vw, 72px);
  color: rgba(255, 255, 255, 0.72);
  background: #091217;
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: var(--white);
  font-weight: 750;
}

.floating-service {
  position: fixed;
  right: clamp(14px, 2.2vw, 28px);
  top: 50%;
  z-index: 30;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 52px;
  padding: 5px;
  border: 1px solid rgba(255, 255, 255, 0.76);
  border-radius: 999px;
  color: var(--teal-dark);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 14px 36px rgba(6, 15, 19, 0.24);
  text-decoration: none;
  transform: translateY(-50%);
  transition:
    transform 160ms ease,
    box-shadow 160ms ease,
    background 160ms ease;
}

.floating-service:hover,
.floating-service:focus-visible {
  background: var(--white);
  box-shadow: 0 18px 46px rgba(6, 15, 19, 0.3);
  transform: translateY(-50%) translateX(-2px);
}

.floating-service__avatar {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  overflow: hidden;
  border-radius: 999px;
  background: var(--white);
}

.floating-service__avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.floating-service__text {
  max-width: 0;
  overflow: hidden;
  white-space: nowrap;
  font-size: 14px;
  font-weight: 850;
  opacity: 0;
  transition:
    max-width 160ms ease,
    opacity 160ms ease,
    padding 160ms ease;
}

.floating-service:hover .floating-service__text,
.floating-service:focus-visible .floating-service__text {
  max-width: 120px;
  padding-right: 10px;
  opacity: 1;
}

@media (max-width: 900px) {
  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    display: grid;
    gap: 0;
    padding: 8px 20px 18px;
    color: var(--ink);
    background: rgba(255, 255, 255, 0.96);
    border-bottom: 1px solid var(--line);
    transform: translateY(-18px);
    opacity: 0;
    pointer-events: none;
    transition:
      transform 160ms ease,
      opacity 160ms ease;
  }

  .site-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .site-nav a {
    padding: 13px 0;
  }

  .hero {
    min-height: 560px;
    height: 84svh;
  }

  .hero-shade {
    background:
      linear-gradient(90deg, rgba(6, 15, 19, 0.92), rgba(6, 15, 19, 0.48)),
      linear-gradient(0deg, rgba(6, 15, 19, 0.28), rgba(6, 15, 19, 0.08));
  }

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

  .platform-copy {
    position: static;
  }

  .service-grid,
  .steps {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 620px) {
  .site-header {
    height: 64px;
    padding: 0 16px;
  }

  .brand-logo {
    width: 36px;
    height: 36px;
  }

  .brand-text {
    font-size: 16px;
  }

  .site-nav {
    top: 64px;
  }

  .hero {
    min-height: 560px;
    height: 86svh;
  }

  .hero-content {
    width: calc(100% - 32px);
    padding-top: 64px;
  }

  .hero h1 {
    font-size: clamp(48px, 16vw, 72px);
  }

  .button {
    width: 100%;
  }

  .intro,
  .section,
  .contact {
    padding-top: 58px;
    padding-bottom: 58px;
  }

  .metrics,
  .service-grid,
  .steps {
    grid-template-columns: 1fr;
  }

  .service-card,
  .steps li {
    min-height: auto;
  }

  .contact-form {
    padding: 20px;
  }

  .wechat-card {
    grid-template-columns: 96px minmax(0, 1fr);
    width: 100%;
  }

  .wechat-card img {
    width: 96px;
  }

  .site-footer {
    display: grid;
  }

  .floating-service {
    top: auto;
    right: 14px;
    bottom: 86px;
    transform: none;
  }

  .floating-service:hover,
  .floating-service:focus-visible {
    transform: translateX(-2px);
  }
}