:root {
  color-scheme: light;
  --bg: #f6fbf8;
  --surface: #ffffff;
  --surface-soft: #eef8f2;
  --ink: #14231b;
  --muted: #587064;
  --subtle: #819288;
  --line: #dbece2;
  --green: #19ad67;
  --green-dark: #108651;
  --green-soft: #eaf8f0;
  --blue: #3778d5;
  --blue-soft: #edf5ff;
  --rose: #f06c8e;
  --rose-soft: #fff0f4;
  --gold: #d9942f;
  --shadow: 0 24px 70px rgb(20 35 27 / 0.12);
  --radius: 18px;
  --max: 1160px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", "PingFang SC", "PingFang TC", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.55;
  overflow-x: hidden;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  background: linear-gradient(180deg, #f9fffb 0%, var(--bg) 48%, #ffffff 100%);
}

a {
  color: inherit;
  text-underline-offset: 4px;
}

p,
h1,
h2,
h3,
strong,
summary,
li {
  overflow-wrap: break-word;
}

.cn,
.en { display: none; }

html[data-lang="zh"] .cn { display: inline; }
html[data-lang="zh"] .cn.block { display: block; }
html[data-lang="en"] .en { display: inline; }
html[data-lang="en"] .en.block { display: block; }

.shell {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgb(249 255 251 / 0.9);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgb(219 236 226 / 0.86);
}

.topbar-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-weight: 850;
  letter-spacing: 0;
}

.brand-icon {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: 0 10px 26px rgb(25 173 103 / 0.22);
}

.nav {
  display: flex;
  align-items: center;
  gap: 18px;
  color: var(--muted);
  font-size: 15px;
}

.nav a {
  text-decoration: none;
  font-weight: 720;
}

.nav a:hover { color: var(--ink); }

.lang-switch {
  border: 1px solid rgb(20 35 27 / 0.16);
  background: var(--surface);
  color: var(--ink);
  border-radius: 999px;
  padding: 7px 13px;
  min-height: 38px;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
  box-shadow: 0 8px 22px rgb(20 35 27 / 0.08);
}

.lang-switch:focus-visible,
.btn:focus-visible,
.nav a:focus-visible,
.footer a:focus-visible {
  outline: 3px solid rgb(25 173 103 / 0.28);
  outline-offset: 3px;
}

.hero-wrap {
  border-bottom: 1px solid rgb(219 236 226 / 0.72);
  background:
    linear-gradient(135deg, rgb(234 248 240 / 0.96), rgb(246 251 248 / 0.88) 46%, rgb(237 245 255 / 0.9)),
    #f6fbf8;
}

.hero {
  min-height: min(720px, calc(100vh - 72px));
  display: grid;
  align-items: center;
  padding: clamp(48px, 8vw, 88px) 0 clamp(42px, 6vw, 72px);
  position: relative;
}

.hero-content {
  width: min(760px, 100%);
  position: relative;
  z-index: 2;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--green-dark);
  font-weight: 850;
}

h1 {
  margin: 0;
  max-width: 820px;
  font-size: clamp(52px, 8.6vw, 98px);
  line-height: 0.98;
  letter-spacing: 0;
}

.lead {
  margin: 24px 0 0;
  max-width: 720px;
  color: var(--muted);
  font-size: clamp(18px, 2vw, 23px);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 22px;
  border: 1.5px solid var(--green-dark);
  border-radius: 999px;
  text-decoration: none;
  font-weight: 850;
  background: var(--green);
  color: #ffffff;
  box-shadow: 0 12px 26px rgb(25 173 103 / 0.2);
}

.btn.secondary {
  background: var(--surface);
  color: var(--ink);
  border-color: var(--line);
  box-shadow: 0 12px 26px rgb(20 35 27 / 0.08);
}

.hero-stage {
  position: absolute;
  inset: 48px 0 32px auto;
  width: min(46vw, 560px);
  min-width: 360px;
  pointer-events: none;
}

.app-icon-large {
  position: absolute;
  right: 42px;
  top: 20px;
  width: 150px;
  height: 150px;
  border-radius: 34px;
  box-shadow: var(--shadow);
}

.phone {
  position: absolute;
  right: 68px;
  bottom: 0;
  width: min(360px, 84%);
  min-height: 560px;
  border: 10px solid #173024;
  border-radius: 42px;
  background: linear-gradient(180deg, #fbfffd, #eef8f2);
  box-shadow: var(--shadow);
  padding: 20px;
  overflow: hidden;
}

.phone::before {
  content: "";
  position: absolute;
  top: 12px;
  left: 50%;
  width: 84px;
  height: 23px;
  transform: translateX(-50%);
  border-radius: 999px;
  background: #173024;
  z-index: 2;
}

.phone-status {
  display: flex;
  justify-content: space-between;
  margin: 18px 6px 22px;
  font-size: 13px;
  font-weight: 820;
}

.persona-strip {
  display: flex;
  gap: 8px;
  margin-bottom: 18px;
  overflow: hidden;
}

.persona-strip span {
  flex: 0 0 auto;
  padding: 7px 10px;
  border-radius: 999px;
  background: #ffffff;
  border: 1px solid var(--line);
  color: var(--green-dark);
  font-size: 12px;
  font-weight: 820;
}

.chat-card {
  display: grid;
  gap: 12px;
}

.bubble {
  padding: 13px 15px;
  border-radius: 20px;
  font-weight: 760;
  box-shadow: 0 10px 22px rgb(20 35 27 / 0.07);
}

.bubble.in {
  width: 82%;
  background: #ffffff;
  border: 1px solid var(--line);
}

.bubble.out {
  width: 88%;
  justify-self: end;
  color: #ffffff;
  background: linear-gradient(135deg, var(--green), #43c978);
}

.action-panel {
  margin-top: 20px;
  padding: 18px;
  border-radius: 24px;
  background: rgb(255 255 255 / 0.86);
  border: 1px solid var(--line);
}

.action-panel strong,
.action-panel span {
  display: block;
}

.action-panel strong {
  font-size: 18px;
}

.action-panel span {
  margin-top: 7px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 720;
}

.mini-tabs {
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: 18px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 6px;
}

.mini-tabs span {
  min-height: 46px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: #f3f3f5;
  color: var(--muted);
  font-size: 12px;
  font-weight: 820;
}

.section {
  padding: 76px 0;
  border-top: 1px solid rgb(219 236 226 / 0.82);
}

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 460px) minmax(0, 1fr);
  gap: 34px;
  align-items: end;
  margin-bottom: 30px;
}

h2 {
  margin: 0;
  font-size: clamp(34px, 4.6vw, 58px);
  line-height: 1.02;
  letter-spacing: 0;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.feature-card {
  min-height: 246px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgb(255 255 255 / 0.94);
  box-shadow: 0 12px 28px rgb(20 35 27 / 0.06);
}

.feature-card.wide {
  grid-column: span 2;
  background: linear-gradient(145deg, #ffffff, var(--green-soft));
}

.feature-icon {
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  margin-bottom: 20px;
  border-radius: 16px;
  color: #ffffff;
  background: linear-gradient(135deg, var(--green), #65d98b);
  font-weight: 900;
}

.feature-card:nth-child(3n) .feature-icon { background: linear-gradient(135deg, var(--blue), #67a7ef); }
.feature-card:nth-child(4n) .feature-icon { background: linear-gradient(135deg, var(--rose), #f5a0b8); }

.feature-card strong {
  display: block;
  font-size: 22px;
  margin-bottom: 10px;
}

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

.persona-section {
  background: linear-gradient(180deg, transparent, rgb(255 255 255 / 0.68));
}

.persona-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
}

.persona-card {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: 0 12px 28px rgb(20 35 27 / 0.055);
}

.persona-card .persona-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 13px;
  color: var(--green-dark);
  background: var(--green-soft);
  font-weight: 900;
  margin-bottom: 14px;
}

.persona-card strong {
  display: block;
  font-size: 20px;
  margin-bottom: 8px;
}

.persona-card p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.privacy-band {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(280px, 0.92fr);
  gap: 28px;
  padding: clamp(28px, 4vw, 42px);
  border: 1.5px solid rgb(20 35 27 / 0.16);
  border-radius: 28px;
  background:
    linear-gradient(135deg, rgb(234 248 240 / 0.96), rgb(237 245 255 / 0.9)),
    var(--surface-soft);
  box-shadow: 0 20px 52px rgb(20 35 27 / 0.08);
}

.privacy-band p:not(.eyebrow) {
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.checklist {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.checklist li {
  padding: 15px 17px;
  border: 1px solid rgb(219 236 226 / 0.96);
  border-radius: 16px;
  background: rgb(255 255 255 / 0.88);
  font-weight: 820;
}

.plans {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.plan {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: 0 12px 28px rgb(20 35 27 / 0.06);
}

.plan.featured {
  border-color: rgb(25 173 103 / 0.42);
  background: linear-gradient(145deg, var(--green-soft), #ffffff);
}

.plan h3 {
  margin: 0 0 16px;
  font-size: 30px;
}

.plan ul {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
}

.plan li { margin: 8px 0; }

.faq {
  display: grid;
  gap: 12px;
}

details {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px 20px;
  background: var(--surface);
  box-shadow: 0 10px 24px rgb(20 35 27 / 0.05);
}

summary {
  cursor: pointer;
  font-weight: 850;
  font-size: 18px;
}

details p {
  margin: 12px 0 0;
  color: var(--muted);
}

.footer {
  min-height: 104px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

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

.footer-links a {
  text-decoration: none;
  font-weight: 720;
}

@media (max-width: 1080px) {
  .hero-stage {
    opacity: 0.36;
    right: -80px;
  }

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

  .persona-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 820px) {
  .section-head,
  .privacy-band,
  .plans {
    grid-template-columns: 1fr;
  }

  .hero-stage {
    display: none;
  }

  .hero {
    min-height: auto;
  }
}

@media (max-width: 720px) {
  .shell {
    width: min(calc(100% - 28px), var(--max));
  }

  .topbar-inner {
    align-items: flex-start;
    flex-direction: column;
    padding: 14px 0;
  }

  .nav {
    width: 100%;
    flex-wrap: wrap;
    overflow-x: visible;
    padding-bottom: 0;
    gap: 10px;
  }

  h1 {
    font-size: 52px;
  }

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

  .feature-card.wide {
    grid-column: auto;
  }

  .footer {
    flex-direction: column;
    align-items: flex-start;
    padding: 26px 0;
  }
}