:root {
  color-scheme: dark;
  font-family: Inter, "Microsoft YaHei", ui-sans-serif, system-ui, sans-serif;
  --bg: #08090c;
  --panel: #12141a;
  --panel-2: #181b23;
  --line: rgba(255, 255, 255, .1);
  --muted: #a3a9b7;
  --text: #f7f8fb;
  --accent: #8b5cf6;
  --accent-2: #5b8cff;
  --green: #22c875;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }

body {
  background:
    radial-gradient(circle at 82% 4%, rgba(91, 140, 255, .18), transparent 32rem),
    radial-gradient(circle at 8% 25%, rgba(139, 92, 246, .14), transparent 30rem),
    var(--bg);
  color: var(--text);
  margin: 0;
}

a { color: inherit; }

.shell {
  margin: 0 auto;
  max-width: 1180px;
  padding: 0 24px;
}

nav {
  align-items: center;
  display: grid;
  column-gap: 34px;
  grid-template-columns: 1fr auto auto;
  padding: 20px 0;
}

.brand {
  align-items: center;
  display: flex;
  font-size: 17px;
  font-weight: 850;
  gap: 9px;
  text-decoration: none;
}

.brand-mark {
  align-items: center;
  background: linear-gradient(145deg, var(--accent), var(--accent-2));
  border-radius: 9px;
  display: flex;
  font-size: 13px;
  height: 30px;
  justify-content: center;
  width: 30px;
}

.links {
  align-items: center;
  display: flex;
  gap: 24px;
  justify-self: end;
}
.links a {
  color: var(--muted);
  font-size: 13px;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
}
.links a:hover {
  color: var(--text);
}

.nav-cta {
  background: white;
  border-radius: 8px;
  color: #101116;
  font-size: 12px;
  font-weight: 750;
  justify-self: end;
  padding: 8px 13px;
  text-decoration: none;
}

.hero {
  align-items: center;
  display: grid;
  gap: 52px;
  grid-template-columns: 1fr .92fr;
  min-height: 670px;
  padding: 70px 0 90px;
}

.eyebrow {
  color: #aa9aff;
  font-size: 10px;
  font-weight: 850;
  letter-spacing: .17em;
}

h1 {
  font-size: clamp(48px, 6vw, 74px);
  letter-spacing: -.065em;
  line-height: 1.03;
  margin: 19px 0 22px;
}

h1 span {
  background: linear-gradient(90deg, #c3b6ff, #81a9ff);
  -webkit-background-clip: text;
  color: transparent;
}

.hero-copy > p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.75;
  margin: 0;
  max-width: 590px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 28px;
}

.button,
.plan-button {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border: 1px solid transparent;
  border-radius: 9px;
  font-size: 13px;
  font-weight: 750;
  padding: 11px 16px;
  text-align: center;
  text-decoration: none;
}

.button.secondary,
.plan-button.secondary {
  background: rgba(255, 255, 255, .04);
  border-color: var(--line);
}

.trust-row {
  color: #b8beca;
  display: flex;
  flex-wrap: wrap;
  font-size: 11px;
  gap: 16px;
  margin-top: 24px;
}

.product-window {
  background: rgba(20, 22, 29, .92);
  border: 1px solid rgba(139, 92, 246, .28);
  border-radius: 18px;
  box-shadow: 0 28px 80px rgba(0, 0, 0, .42);
  overflow: hidden;
  transform: perspective(1000px) rotateY(-4deg) rotateX(2deg);
}

.window-bar {
  align-items: center;
  background: #0e1015;
  color: #8f95a3;
  display: flex;
  font-size: 10px;
  gap: 6px;
  padding: 12px 14px;
}

.window-bar i { background: #3b3e48; border-radius: 50%; height: 6px; width: 6px; }
.window-bar span { margin-left: 5px; }

.product-title {
  background: linear-gradient(135deg, rgba(139, 92, 246, .22), rgba(91, 140, 255, .12));
  display: grid;
  gap: 5px;
  padding: 25px;
}

.product-title strong { font-size: 21px; }
.product-title span { color: #b0b6c4; font-size: 11px; }
.platform-list { display: grid; gap: 8px; padding: 14px; }

.platform-list > div {
  align-items: center;
  background: rgba(255, 255, 255, .035);
  border: 1px solid var(--line);
  border-radius: 11px;
  display: grid;
  gap: 11px;
  grid-template-columns: 36px 1fr auto;
  padding: 10px;
}

.platform {
  align-items: center;
  border-radius: 9px;
  display: flex;
  font-size: 11px;
  height: 36px;
  justify-content: center;
  width: 36px;
}

.platform.x { background: #07080b; }
.platform.zhihu { background: #1772f6; }
.platform.wechat { background: #09bb68; }
.platform.red { background: #ff2442; font-size: 8px; }
.platform-list span { display: grid; gap: 2px; }
.platform-list strong { font-size: 12px; }
.platform-list small { color: var(--muted); font-size: 9px; }
.platform-list em { background: #302b45; border-radius: 7px; color: #d8ceff; font-size: 9px; font-style: normal; padding: 6px 10px; }

.section { padding: 80px 0; }
.section-heading { margin-bottom: 35px; }
.section-heading.centered { text-align: center; }
.section-heading h2, .buy-panel h2 { font-size: clamp(30px, 4vw, 45px); letter-spacing: -.045em; margin: 12px 0; }
.section-heading p, .buy-panel p { color: var(--muted); font-size: 14px; line-height: 1.7; margin: 0 auto; max-width: 650px; }

.video-frame {
  background: #0d0f14;
  border: 1px solid rgba(139, 92, 246, .25);
  border-radius: 19px;
  box-shadow: 0 25px 70px rgba(0, 0, 0, .38);
  overflow: hidden;
  padding: 10px;
}

.video-frame video { aspect-ratio: 16 / 9; background: #050608; border-radius: 12px; display: block; object-fit: contain; width: 100%; }
.video-note { align-items: center; color: #cdd2dc; display: flex; font-size: 11px; justify-content: space-between; padding: 11px 6px 2px; }
.video-note small { color: var(--muted); }
.video-note code { color: #b9aaff; }

.steps { display: grid; gap: 14px; grid-template-columns: repeat(3, 1fr); }
.steps article { background: var(--panel); border: 1px solid var(--line); border-radius: 15px; padding: 22px; }
.steps span { color: #9b87ff; font-size: 11px; font-weight: 850; letter-spacing: .12em; }
.steps h3 { font-size: 17px; margin: 18px 0 8px; }
.steps p, .plan-card li, .buy-panel p, .legal p, .legal li { color: var(--muted); font-size: 13px; line-height: 1.7; }

.pricing-section { padding-top: 95px; }
.pricing-grid { display: grid; gap: 18px; grid-template-columns: 1fr 1fr; margin: 0 auto; max-width: 930px; }
.pricing-grid.three-plans { grid-template-columns: repeat(3, 1fr); max-width: 1120px; }
.plan-card { background: var(--panel); border: 1px solid var(--line); border-radius: 18px; padding: 25px; position: relative; }
.plan-card.featured { background: radial-gradient(circle at 100% 0, rgba(139, 92, 246, .2), transparent 45%), var(--panel); border-color: rgba(139, 92, 246, .52); }
.recommended { background: var(--accent); border-radius: 999px; font-size: 9px; font-weight: 800; padding: 5px 9px; position: absolute; right: 18px; top: -12px; }
.plan-header { align-items: start; display: flex; justify-content: space-between; min-height: 75px; }
.plan-label { color: #c7bcff; font-size: 13px; font-weight: 800; }
.plan-header h3 { color: var(--muted); font-size: 12px; font-weight: 500; margin: 6px 0; }
.plan-header > strong { font-size: 26px; letter-spacing: -.04em; white-space: nowrap; }
.plan-header small { color: var(--muted); font-size: 10px; font-weight: 500; }
.plan-button { display: block; margin: 15px 0 21px; }
.plan-card ul { border-top: 1px solid var(--line); display: grid; gap: 11px; list-style: none; margin: 0; padding: 20px 0 0; }
.plan-card li { padding-left: 20px; position: relative; }
.plan-card li::before { color: var(--green); content: "✓"; font-weight: 800; left: 0; position: absolute; }
.plan-card li b { color: var(--text); }

.comparison { border: 1px solid var(--line); border-radius: 15px; margin: 28px auto 0; max-width: 930px; overflow: hidden; }
.comparison-row { align-items: center; border-top: 1px solid var(--line); display: grid; font-size: 12px; grid-template-columns: 1.5fr 1fr 1fr; padding: 13px 17px; }
.comparison-row:first-child { border: 0; }
.comparison-row span { color: #d8dce5; }
.comparison-row strong { color: var(--muted); font-weight: 550; text-align: center; }
.comparison-head { background: rgba(255, 255, 255, .045); }
.comparison-head strong { color: var(--text); font-weight: 800; }

.buy-panel {
  align-items: start;
  background:
    radial-gradient(circle at 16% 18%, rgba(139, 92, 246, .24), transparent 28rem),
    linear-gradient(135deg, rgba(24, 20, 45, .96), rgba(12, 14, 24, .96));
  border: 1px solid rgba(139, 92, 246, .34);
  border-radius: 22px;
  box-shadow: 0 28px 90px rgba(0, 0, 0, .34);
  display: grid;
  gap: 30px;
  grid-template-columns: minmax(360px, .9fr) minmax(420px, 1.1fr);
  margin: 20px 0 90px;
  padding: 32px;
}
.buy-panel h2 { font-size: 34px; margin-bottom: 12px; }
.buy-panel p { margin: 0; }
.buy-intro { position: static; }
.purchase-options { display: grid; gap: 10px; grid-template-columns: 1fr 1fr; margin-top: 24px; }
.purchase-options > div {
  background: rgba(8, 9, 12, .68);
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 13px;
  display: grid;
  gap: 5px;
  padding: 14px;
}
.purchase-options > div.selected {
  background: linear-gradient(135deg, rgba(139, 92, 246, .24), rgba(91, 140, 255, .08));
  border-color: rgba(139, 92, 246, .7);
}
.purchase-options span { color: #b8bfd0; font-size: 10px; }
.purchase-options strong { font-size: 24px; letter-spacing: -.045em; }
.purchase-options small { color: #c9cfdd; font-size: 13px; font-weight: 650; margin-left: 1px; }
.wechat-qr-card {
  align-items: center;
  background: rgba(8, 9, 12, .64);
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 16px;
  display: grid;
  gap: 18px;
  grid-template-columns: 178px minmax(235px, 1fr);
  margin-top: 12px;
  padding: 16px;
}
.wechat-qr-card img {
  background: white;
  border-radius: 13px;
  display: block;
  height: auto;
  max-width: 178px;
  object-fit: contain;
  padding: 5px;
  width: 100%;
}
.wechat-qr-card div { align-content: center; display: grid; gap: 10px; text-align: left; }
.wechat-qr-card strong { font-size: 14.5px; letter-spacing: -.04em; white-space: nowrap; }
.wechat-qr-card span { align-items: center; background: rgba(139, 92, 246, .15); border: 1px solid rgba(139, 92, 246, .28); border-radius: 999px; color: #d9d2ff; display: inline-flex; font-size: 12px; gap: 5px; justify-self: start; line-height: 1; padding: 7px 10px; }
.wechat-qr-card span b { color: white; font-size: 13px; }
.purchase-flow {
  align-self: center;
  display: grid;
  gap: 12px;
  padding-top: 6px;
}
.purchase-flow article {
  align-items: start;
  background: rgba(8, 9, 12, .58);
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 15px;
  display: grid;
  gap: 14px;
  grid-template-columns: 36px 1fr;
  padding: 18px;
}
.purchase-flow article > span {
  align-items: center;
  background: rgba(139, 92, 246, .18);
  border: 1px solid rgba(139, 92, 246, .28);
  border-radius: 999px;
  color: #c9bdff;
  display: flex;
  font-size: 10px;
  font-weight: 850;
  height: 28px;
  justify-content: center;
  letter-spacing: .08em;
  width: 28px;
}
.purchase-flow article strong { font-size: 16px; }
.purchase-flow article p { font-size: 12px; line-height: 1.65; margin-top: 6px; }
.service-card {
  align-items: center;
  background: linear-gradient(135deg, rgba(139, 92, 246, .28), rgba(91, 140, 255, .12));
  border: 1px solid rgba(139, 92, 246, .42);
  border-radius: 15px;
  display: flex;
  gap: 18px;
  justify-content: space-between;
  padding: 16px 18px;
}
.service-card div { display: grid; gap: 4px; }
.service-card small, .service-card > span { color: #c4c9d8; font-size: 11px; }
.service-card strong { font-size: 14px; }

.legal { margin: 50px auto 80px; max-width: 820px; }
.legal h1 { font-size: 42px; margin: 25px 0; }
.legal h2 { margin-top: 32px; }

footer { border-top: 1px solid var(--line); color: var(--muted); display: flex; font-size: 11px; gap: 18px; justify-content: space-between; padding: 24px 0 32px; }

@media (max-width: 900px) {
  nav { grid-template-columns: 1fr auto; }
  .links { display: none; }
  .hero { grid-template-columns: 1fr; padding-top: 55px; }
  .hero-product { margin: 0 auto; max-width: 600px; width: 100%; }
  .product-window { transform: none; }
  .steps, .pricing-grid, .pricing-grid.three-plans { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  .shell { padding: 0 16px; }
  h1 { font-size: 43px; }
  .hero { min-height: auto; padding-bottom: 55px; }
  .section { padding: 55px 0; }
  .video-note { align-items: start; flex-direction: column; gap: 4px; }
  .comparison-row { font-size: 10px; grid-template-columns: 1.2fr .8fr .8fr; padding: 11px 9px; }
  .buy-panel { grid-template-columns: 1fr; padding: 22px; }
  .buy-intro { position: static; }
  .purchase-options { grid-template-columns: 1fr 1fr; }
  .service-card { align-items: start; flex-direction: column; gap: 6px; }
  footer { flex-direction: column; }
}

.purchase-generator {
  background: rgba(8, 9, 12, .64);
  border: 1px solid rgba(139, 92, 246, .28);
  border-radius: 16px;
  display: grid;
  gap: 10px;
  margin-top: 12px;
  padding: 16px;
}

.generator-header {
  display: grid;
  gap: 4px;
}

.generator-header strong {
  font-size: 15px;
}

.generator-header span,
.purchase-generator label,
.generator-status {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.55;
}

.generator-plans {
  background: rgba(255, 255, 255, .04);
  border-radius: 10px;
  display: grid;
  gap: 6px;
  grid-template-columns: 1fr 1fr;
  padding: 5px;
}

.generator-plans button {
  background: transparent;
  border: 0;
  border-radius: 8px;
  color: #cdd3e0;
  cursor: pointer;
  font: inherit;
  font-size: 12px;
  font-weight: 750;
  min-height: 34px;
}

.generator-plans button.selected {
  background: rgba(139, 92, 246, .28);
  color: white;
}

.purchase-generator input {
  background: rgba(4, 5, 8, .78);
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 10px;
  color: var(--text);
  font: inherit;
  font-size: 13px;
  outline: none;
  padding: 12px 13px;
  text-transform: uppercase;
  width: 100%;
}

.purchase-generator input:focus {
  border-color: rgba(139, 92, 246, .65);
  box-shadow: 0 0 0 3px rgba(139, 92, 246, .12);
}

.purchase-generator .button {
  cursor: pointer;
  width: 100%;
}

.generator-status {
  margin: 0;
}

.generator-status.error {
  color: #ff9d9d;
}