:root {
  --bg: #f4f7fb;
  --ink: #0b1220;
  --muted: #5b667a;
  --accent: #2563eb;
  --accent-2: #06b6d4;
  --accent-3: #0f172a;
  --card: #ffffff;
  --card-2: #eef4ff;
  --line: rgba(15, 23, 42, 0.12);
  --shadow: 0 24px 60px rgba(15, 23, 42, 0.16);
  --shadow-soft: 0 14px 32px rgba(15, 23, 42, 0.12);
  --radius: 20px;
  --font-body: "Manrope", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-display: "Space Grotesk", "Manrope", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: linear-gradient(160deg, #f7fbff 0%, #eef3fb 50%, #f5f7fb 100%);
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

body::before,
body::after {
  content: "";
  position: fixed;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  pointer-events: none;
  z-index: -1;
}

body::before {
  top: -160px;
  right: -120px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.2), transparent 65%);
}

body::after {
  bottom: -220px;
  left: -140px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.2), transparent 65%);
}

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

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

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(16px);
  background: rgba(245, 248, 255, 0.9);
  border-bottom: 1px solid rgba(15, 23, 42, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 12px 0;
}

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

.brand-logo {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  box-shadow: 0 12px 22px rgba(15, 23, 42, 0.18);
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  color: var(--muted);
  font-size: 14px;
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-sm {
  padding: 6px 12px;
  font-size: 12px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #ffffff;
  box-shadow: 0 16px 30px rgba(37, 99, 235, 0.28);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
  border-color: rgba(15, 23, 42, 0.2);
}

.btn-ghost {
  background: var(--card);
  border-color: rgba(15, 23, 42, 0.14);
  box-shadow: var(--shadow-soft);
}

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

.hero {
  padding: 30px 0 20px;
}

#download,
#features,
#steps {
  scroll-margin-top: 60px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 0.92fr);
  gap: 36px;
  align-items: center;
}

.hero-copy {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.eyebrow {
  align-self: flex-start;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(37, 99, 235, 0.12);
  color: var(--accent-3);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.hero-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(40px, 5vw, 68px);
  line-height: 1.02;
  display: grid;
  gap: 6px;
}

.hero-title span {
  font-size: clamp(18px, 2.4vw, 26px);
  font-weight: 600;
  color: var(--accent-2);
  letter-spacing: 0.02em;
}

.hero-subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--muted);
  font-size: 12px;
}

.hero-tags span {
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid rgba(15, 23, 42, 0.12);
  background: rgba(255, 255, 255, 0.8);
}

.hero-panel {
  position: relative;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(241, 246, 255, 0.98));
  border: 1px solid rgba(15, 23, 42, 0.12);
  border-radius: calc(var(--radius) + 6px);
  padding: 20px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.hero-panel::before {
  content: "";
  position: absolute;
  top: -80px;
  right: -60px;
  width: 160px;
  height: 160px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.2), transparent 70%);
}

.panel-head h2 {
  margin: 6px 0 6px;
  font-family: var(--font-display);
  font-size: 24px;
}

.panel-head p {
  margin: 0;
  color: var(--muted);
}

.panel-kicker {
  margin: 0;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent-3);
}

.platform-list {
  margin-top: 12px;
  display: grid;
  gap: 10px;
}

.platform-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  border-radius: 16px;
  background: var(--card);
  border: 1px solid rgba(15, 23, 42, 0.12);
  box-shadow: var(--shadow-soft);
}

.platform-card.featured {
  background: linear-gradient(120deg, rgba(37, 99, 235, 0.18), rgba(255, 255, 255, 0.98));
  border-color: rgba(37, 99, 235, 0.35);
}

.platform-info h3 {
  margin: 0;
  font-size: 16px;
}

.platform-info p {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 12px;
}

.platform-btn {
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--accent);
  color: #ffffff;
  font-size: 12px;
  font-weight: 600;
}

.platform-btn.light {
  background: var(--accent-3);
}

.panel-foot {
  margin-top: 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--muted);
  font-size: 12px;
}

.panel-foot span {
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--card-2);
  border: 1px solid rgba(15, 23, 42, 0.1);
}

.band {
  padding: 20px 0 44px;
}

.band-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  background: linear-gradient(135deg, #0f172a, #1e293b);
  border-radius: calc(var(--radius) + 8px);
  padding: 22px;
  color: #e2e8f0;
  box-shadow: var(--shadow);
}

.band-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 12px 14px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 16px;
}

.band-value {
  font-family: var(--font-display);
  font-size: 20px;
}

.band-label {
  font-size: 12px;
  color: rgba(226, 232, 240, 0.72);
}

.section {
  padding: 20px 0;
}

.section-head {
  margin-bottom: 28px;
}

.section-kicker {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
}

.section h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 30px;
}

.section p {
  margin: 0;
  color: var(--muted);
}

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

.feature-card {
  background: var(--card);
  padding: 20px;
  border-radius: var(--radius);
  border: 1px solid rgba(15, 23, 42, 0.12);
  box-shadow: var(--shadow-soft);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.feature-index {
  font-family: var(--font-display);
  color: var(--accent);
  font-size: 18px;
}

.feature-card h3 {
  margin: 0;
}

.feature-card p {
  margin: 0;
  color: var(--muted);
}

.feature-banner {
  margin-top: 22px;
  padding: 18px;
  border-radius: calc(var(--radius) + 6px);
  background: linear-gradient(120deg, rgba(37, 99, 235, 0.16), rgba(255, 255, 255, 0.94));
  border: 1px solid rgba(37, 99, 235, 0.25);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.banner-kicker {
  margin: 0 0 6px;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent-3);
}

.feature-banner h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
}

.feature-banner p {
  margin: 0;
  color: var(--muted);
}

.banner-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

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

.step-card {
  background: var(--card);
  padding: 20px;
  border-radius: var(--radius);
  border: 1px solid rgba(15, 23, 42, 0.12);
  box-shadow: var(--shadow-soft);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.step-index {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: rgba(37, 99, 235, 0.14);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 600;
}

.step-card h3 {
  margin: 0;
}

.step-card p {
  margin: 0;
  color: var(--muted);
}


.cta-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: 24px;
  align-items: center;
}

.cta-card {
  background: #0f172a;
  color: #e2e8f0;
  border-radius: calc(var(--radius) + 10px);
  padding: 24px;
  box-shadow: var(--shadow);
}

.cta-kicker {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(226, 232, 240, 0.6);
}

.cta-card h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 30px;
}

.cta-card p {
  margin: 0;
  color: rgba(226, 232, 240, 0.7);
}

.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.cta-actions .btn-outline {
  color: #e2e8f0;
  border-color: rgba(226, 232, 240, 0.4);
}

.cta-aside {
  display: grid;
  gap: 16px;
}

.cta-note {
  background: var(--card);
  border-radius: var(--radius);
  padding: 20px;
  border: 1px solid rgba(15, 23, 42, 0.12);
  box-shadow: var(--shadow-soft);
}

.cta-note h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
}

.cta-note p {
  margin: 0;
  color: var(--muted);
}

.site-footer {
  padding: 24px 0 36px;
  border-top: 1px solid rgba(15, 23, 42, 0.1);
  background: rgba(245, 248, 255, 0.92);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 16px;
}

@media (max-width: 1000px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .cta-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 900px) {
  .site-header {
    position: static;
  }

  .nav-links {
    display: none;
  }

  .feature-grid,
  .steps-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .band-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .banner-actions {
    width: 100%;
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 16px;
  }

  .header-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 10px 0;
  }

  .brand-logo {
    width: 38px;
    height: 38px;
  }

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

  .nav-cta {
    width: auto;
    flex-direction: row;
    align-self: center;
  }

  .hero {
    padding: 20px 0 40px;
  }

  .hero-copy {
    gap: 12px;
  }

  .hero-actions,
  .cta-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

  .feature-grid,
  .steps-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .band {
    padding: 16px 0 36px;
  }

  .section {
    padding: 24px 0;
  }


  .band-grid {
    padding: 16px;
  }

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