:root {
  color-scheme: dark;
  --bg: #09090b;
  --panel: #101815;
  --panel-strong: #13211c;
  --text: #f5faf7;
  --muted: #a7b5ae;
  --line: #253d34;
  --brand: #10b981;
  --brand-soft: #d1fae5;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 15% 8%, rgba(16, 185, 129, 0.14), transparent 27rem),
    radial-gradient(circle at 85% 30%, rgba(16, 185, 129, 0.08), transparent 24rem),
    var(--bg);
  color: var(--text);
  font-family: Inter, "Microsoft YaHei UI", "PingFang SC", system-ui, sans-serif;
  line-height: 1.65;
}

a { color: inherit; text-decoration: none; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 74px;
  padding: 0 max(24px, calc((100vw - 1180px) / 2));
  border-bottom: 1px solid rgba(255,255,255,.07);
  background: rgba(9,9,11,.86);
  backdrop-filter: blur(18px);
}
.brand { display: flex; align-items: center; gap: 12px; font-size: 20px; font-weight: 800; }
.brand-mark { display: grid; width: 40px; height: 40px; place-items: center; }
.brand-mark svg { width: 100%; height: 100%; fill: none; stroke: var(--brand); stroke-linecap: round; stroke-linejoin: round; stroke-width: 3; }
.brand-mark svg circle, .brand-mark svg .spark { fill: var(--brand); stroke: none; }
nav { display: flex; gap: 30px; color: var(--muted); font-size: 14px; }
nav a:hover { color: var(--text); }

main { overflow: hidden; }
.hero, .section, .download-section, footer { width: min(1180px, calc(100% - 48px)); margin-inline: auto; }
.hero {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 74px;
  align-items: center;
  min-height: 720px;
  padding: 80px 0;
}
.eyebrow { margin: 0 0 12px; color: var(--brand); font-size: 13px; font-weight: 800; letter-spacing: .13em; text-transform: uppercase; }
h1, h2, h3, p { overflow-wrap: anywhere; }
h1 { max-width: 760px; margin: 0; font-size: clamp(40px, 5.4vw, 72px); line-height: 1.11; letter-spacing: -.04em; }
.hero-description { max-width: 670px; margin: 26px 0 0; color: var(--muted); font-size: 19px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 36px; }
.primary-button, .secondary-button, .disabled-button { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 22px; border-radius: 13px; font-weight: 800; }
.primary-button { background: var(--brand); color: #04140e; }
.secondary-button { border: 1px solid var(--line); background: rgba(255,255,255,.03); }
.hero-status { display: flex; flex-wrap: wrap; gap: 18px; padding: 0; margin: 28px 0 0; color: var(--muted); font-size: 13px; list-style: none; }
.hero-status li { display: flex; align-items: center; gap: 8px; }
.hero-status li span { width: 7px; height: 7px; border-radius: 50%; background: var(--brand); box-shadow: 0 0 14px var(--brand); }

.product-card { position: relative; padding: 28px; border: 1px solid var(--line); border-radius: 28px; background: linear-gradient(145deg, rgba(19,33,28,.98), rgba(11,15,13,.96)); box-shadow: 0 34px 90px rgba(0,0,0,.4); }
.product-card::before { position: absolute; inset: -1px; z-index: -1; border-radius: inherit; background: linear-gradient(135deg, rgba(16,185,129,.55), transparent 38%); content: ""; filter: blur(18px); opacity: .45; }
.product-topline { display: flex; gap: 7px; }
.product-topline span { width: 8px; height: 8px; border-radius: 50%; background: #385047; }
.mini-label { margin: 34px 0 6px; color: var(--brand); font-size: 11px; font-weight: 900; letter-spacing: .15em; }
.product-card h2 { margin: 0 0 26px; font-size: 30px; }
.prompt-card { margin-top: 12px; padding: 17px 18px; border: 1px solid #29473c; border-radius: 15px; background: rgba(255,255,255,.025); color: #dce9e2; }
.mock-nav { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; margin: 28px -10px -10px; padding: 16px 8px 4px; border-top: 1px solid var(--line); color: #74877e; font-size: 11px; text-align: center; }
.mock-nav b { color: var(--brand); }

.section { padding: 100px 0; border-top: 1px solid rgba(255,255,255,.07); }
.section-heading { max-width: 720px; }
.section-heading h2, .download-section h2, .security-section h2 { margin: 0; font-size: clamp(32px, 4vw, 48px); line-height: 1.2; letter-spacing: -.03em; }
.section-heading > p:last-child { color: var(--muted); }
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-top: 48px; }
.feature-grid article { min-height: 230px; padding: 28px; border: 1px solid var(--line); border-radius: 22px; background: rgba(16,24,21,.82); }
.feature-grid b { color: var(--brand); font-size: 13px; }
.feature-grid h3 { margin: 44px 0 8px; font-size: 21px; }
.feature-grid p { margin: 0; color: var(--muted); font-size: 14px; }

.split-section { display: grid; grid-template-columns: .9fr 1.1fr; gap: 90px; align-items: start; }
.steps { display: grid; gap: 15px; padding: 0; margin: 0; list-style: none; }
.steps li { display: grid; grid-template-columns: 48px 1fr; gap: 18px; align-items: center; padding: 20px; border: 1px solid var(--line); border-radius: 18px; background: var(--panel); }
.steps li > span { display: grid; width: 46px; height: 46px; place-items: center; border-radius: 50%; background: var(--brand); color: #06140f; font-weight: 900; }
.steps h3, .steps p { margin: 0; }
.steps h3 { font-size: 17px; }
.steps p { color: var(--muted); font-size: 13px; }

.security-section { display: grid; grid-template-columns: 1fr 1fr; gap: 90px; align-items: center; padding: 70px; border: 1px solid var(--line); border-radius: 30px; background: linear-gradient(135deg, #10251d, #0e1512); }
.security-copy { color: var(--muted); }
.security-copy p { margin: 0 0 12px; }
.download-section { display: flex; align-items: center; justify-content: space-between; gap: 40px; padding: 110px 0; }
.download-section > div { max-width: 720px; }
.download-section p:last-child { color: var(--muted); }
.disabled-button { flex: 0 0 auto; border: 1px solid var(--line); color: var(--muted); cursor: not-allowed; }
footer { display: flex; justify-content: space-between; gap: 30px; padding: 34px 0 50px; border-top: 1px solid rgba(255,255,255,.07); color: #778a81; font-size: 12px; }
footer p { margin: 0; }

@media (max-width: 900px) {
  nav { display: none; }
  .hero, .split-section, .security-section { grid-template-columns: 1fr; }
  .hero { gap: 50px; min-height: auto; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .security-section { gap: 28px; padding: 42px; }
}

@media (max-width: 580px) {
  .site-header { height: 64px; padding-inline: 18px; }
  .hero, .section, .download-section, footer { width: min(100% - 32px, 1180px); }
  .hero { padding: 60px 0 70px; }
  h1 { font-size: 39px; }
  .hero-description { font-size: 16px; }
  .feature-grid { grid-template-columns: 1fr; }
  .section { padding: 74px 0; }
  .security-section { width: calc(100% - 32px); padding: 30px 24px; }
  .download-section, footer { flex-direction: column; align-items: flex-start; }
  .disabled-button { width: 100%; }
  footer { gap: 8px; }
}