:root {
  --ink: #15171a;
  --muted: #606873;
  --line: #dde3ea;
  --soft: #f5f7fa;
  --paper: #ffffff;
  --cyan: #19a7ce;
  --green: #23b47e;
  --amber: #e2a124;
  --graphite: #252c34;
  --shadow: 0 18px 50px rgba(24, 35, 48, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.6;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 28px;
  min-height: 72px;
  padding: 12px clamp(20px, 4vw, 64px);
  background: rgba(255, 255, 255, 0.86);
  border-bottom: 1px solid rgba(221, 227, 234, 0.7);
  backdrop-filter: blur(18px);
}

.site-header.is-scrolled {
  box-shadow: 0 8px 30px rgba(21, 23, 26, 0.07);
}

.brand,
.site-nav,
.header-actions,
.hero-actions,
.model-list,
.hero-stats,
.price-row,
.site-footer {
  display: flex;
  align-items: center;
}

.brand {
  font-weight: 800;
  letter-spacing: 0;
}

.site-nav {
  justify-content: center;
  gap: 28px;
  color: #3d444d;
  font-size: 15px;
}

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

.site-nav a:hover,
.ghost-link:hover {
  color: var(--cyan);
}

.header-actions {
  gap: 14px;
}

.ghost-link {
  color: var(--graphite);
  font-weight: 650;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-weight: 750;
  transition:
    transform 0.2s ease,
    box-shadow 0.2s ease,
    border-color 0.2s ease,
    background 0.2s ease;
}

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

.button-dark {
  color: white;
  background: var(--ink);
  box-shadow: 0 12px 28px rgba(21, 23, 26, 0.18);
}

.button-light {
  color: var(--ink);
  background: white;
  border-color: var(--line);
}

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

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

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(360px, 1.08fr);
  gap: clamp(30px, 5vw, 70px);
  align-items: center;
  min-height: calc(100vh - 72px);
  padding: clamp(52px, 8vw, 96px) clamp(20px, 4vw, 64px) 42px;
  overflow: hidden;
}

.hero-copy {
  max-width: 670px;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--green);
  font-size: 13px;
  font-weight: 850;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

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

h1 {
  margin-bottom: 22px;
  font-size: clamp(44px, 6.8vw, 86px);
  line-height: 1.04;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1.12;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  font-size: 21px;
  line-height: 1.25;
}

.hero-text,
.section-heading p,
.band-copy p,
.final-cta h2 + p {
  color: var(--muted);
  font-size: 18px;
}

.hero-actions {
  flex-wrap: wrap;
  gap: 14px;
  margin: 34px 0 34px;
}

.hero-stats {
  flex-wrap: wrap;
  gap: 18px;
  margin: 0;
}

.hero-stats div {
  min-width: 128px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfd;
}

.hero-stats dt {
  font-size: 25px;
  font-weight: 850;
}

.hero-stats dd {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.hero-visual {
  position: relative;
  min-height: 520px;
}

.hero-visual::before {
  position: absolute;
  inset: 8% 2% auto 12%;
  height: 74%;
  content: "";
  background:
    radial-gradient(circle at 20% 20%, rgba(35, 180, 126, 0.24), transparent 28%),
    radial-gradient(circle at 80% 28%, rgba(25, 167, 206, 0.22), transparent 30%),
    linear-gradient(135deg, #eef7f8, #ffffff);
  border-radius: 8px;
  transform: rotate(-3deg);
}

.hero-visual img {
  position: relative;
  z-index: 1;
  width: min(720px, 110%);
  margin: 0 auto;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.model-strip {
  padding: 22px clamp(20px, 4vw, 64px) 34px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: #fbfcfd;
}

.model-strip p {
  margin-bottom: 16px;
  color: var(--muted);
  text-align: center;
}

.model-list {
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.model-list span {
  padding: 10px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: white;
  font-weight: 750;
}

.section,
.faq-section {
  padding: clamp(72px, 9vw, 118px) clamp(20px, 4vw, 64px);
}

.section-heading {
  max-width: 780px;
  margin: 0 auto 42px;
  text-align: center;
}

.section-heading.compact {
  margin-bottom: 30px;
}

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

.feature-card,
.steps article,
.pricing-panel,
.faq-list details {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: white;
}

.feature-card {
  padding: 28px;
  box-shadow: 0 10px 34px rgba(24, 35, 48, 0.06);
}

.feature-card p,
.feature-card li,
.steps p,
.faq-list p {
  color: var(--muted);
}

.icon {
  display: grid;
  width: 42px;
  height: 42px;
  margin-bottom: 22px;
  place-items: center;
  color: white;
  background: var(--graphite);
  border-radius: 8px;
  font-weight: 850;
}

.feature-card:nth-child(2) .icon {
  background: var(--cyan);
}

.feature-card:nth-child(3) .icon {
  background: var(--green);
}

.feature-card:nth-child(4) .icon {
  background: var(--amber);
}

.feature-card ul {
  display: grid;
  gap: 8px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.feature-card li::before {
  margin-right: 8px;
  color: var(--green);
  content: "✓";
  font-weight: 800;
}

.band {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 0.8fr);
  gap: clamp(30px, 5vw, 70px);
  align-items: center;
  padding: clamp(72px, 8vw, 104px) clamp(20px, 4vw, 64px);
  background: #eef4f2;
}

.band-copy {
  max-width: 720px;
}

.pricing-panel {
  padding: 10px;
  box-shadow: var(--shadow);
}

.price-row {
  justify-content: space-between;
  gap: 18px;
  padding: 18px;
  border-bottom: 1px solid var(--line);
}

.price-row:last-child {
  border-bottom: 0;
}

.price-row span {
  color: var(--muted);
}

.price-row strong {
  text-align: right;
}

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

.steps article {
  padding: 28px;
}

.steps span {
  display: block;
  margin-bottom: 18px;
  color: var(--cyan);
  font-size: 14px;
  font-weight: 850;
}

.faq-section {
  background: var(--soft);
}

.faq-list {
  display: grid;
  max-width: 920px;
  margin: 0 auto;
  gap: 12px;
}

.faq-list details {
  padding: 0 22px;
}

.faq-list summary {
  cursor: pointer;
  padding: 20px 0;
  font-size: 18px;
  font-weight: 800;
}

.faq-list summary::marker {
  color: var(--cyan);
}

.faq-list p {
  margin-bottom: 22px;
}

.final-cta {
  padding: clamp(70px, 8vw, 110px) clamp(20px, 4vw, 64px);
  text-align: center;
  color: white;
  background:
    linear-gradient(120deg, rgba(21, 23, 26, 0.96), rgba(37, 44, 52, 0.94)),
    radial-gradient(circle at 30% 0%, rgba(25, 167, 206, 0.5), transparent 34%);
}

.final-cta .eyebrow {
  color: #75e0b8;
}

.final-cta h2 {
  max-width: 820px;
  margin-right: auto;
  margin-left: auto;
}

.final-cta .button-dark {
  margin-top: 18px;
  color: var(--ink);
  background: white;
}

.site-footer {
  justify-content: space-between;
  gap: 16px;
  padding: 26px clamp(20px, 4vw, 64px);
  color: var(--muted);
  border-top: 1px solid var(--line);
}

@media (max-width: 1040px) {
  .feature-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-visual {
    min-height: auto;
  }
}

@media (max-width: 760px) {
  .site-header {
    grid-template-columns: auto auto;
  }

  .nav-toggle {
    display: block;
    justify-self: end;
  }

  .site-nav,
  .header-actions {
    display: none;
  }

  .site-nav.is-open,
  .header-actions.is-open {
    display: flex;
    grid-column: 1 / -1;
    justify-content: flex-start;
  }

  .site-nav.is-open {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }

  .header-actions.is-open {
    flex-wrap: wrap;
  }

  .hero {
    padding-top: 42px;
  }

  h1 {
    font-size: clamp(38px, 12vw, 58px);
  }

  .hero-stats,
  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .hero-stats div,
  .button {
    width: 100%;
  }

  .hero-visual img {
    width: 100%;
  }

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

  .price-row {
    align-items: flex-start;
    flex-direction: column;
  }

  .price-row strong {
    text-align: left;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }
}