:root {
  --bg: #f5f8f7;
  --surface: #ffffff;
  --surface-soft: #e8f7f4;
  --ink: #111c22;
  --muted: #54636b;
  --line: #d7e1df;
  --primary: #007a82;
  --primary-dark: #005c64;
  --accent: #d89d2b;
  --shadow: 0 20px 60px rgba(17, 28, 34, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  color: var(--primary-dark);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(20px, 5vw, 72px);
  background: rgba(245, 248, 247, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 800;
  white-space: nowrap;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), #0ea79f);
  box-shadow: 0 10px 24px rgba(0, 122, 130, 0.22);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 24px);
  flex-wrap: wrap;
  font-size: 14px;
  color: var(--muted);
}

.site-nav a {
  color: var(--muted);
}

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

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.8fr);
  align-items: center;
  gap: clamp(32px, 6vw, 88px);
  max-width: 1160px;
  margin: 0 auto;
  padding: clamp(48px, 8vw, 96px) clamp(20px, 5vw, 72px) 56px;
}

.hero h1,
.doc-page h1 {
  margin: 0;
  font-size: clamp(44px, 7vw, 86px);
  line-height: 1.05;
  letter-spacing: 0;
}

.hero p {
  max-width: 640px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: clamp(17px, 2vw, 22px);
}

.hero-contact {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  padding: 10px 14px;
  border-radius: 8px;
  color: var(--ink);
  background: #fff4d9;
  border: 1px solid rgba(216, 157, 43, 0.36);
  font-size: 15px;
}

.hero-contact strong {
  color: var(--primary-dark);
  font-size: 17px;
}

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

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 8px;
  font-weight: 800;
}

.primary-button {
  color: #fff;
  background: var(--primary);
}

.primary-button:hover {
  color: #fff;
  background: var(--primary-dark);
}

.secondary-button {
  color: var(--primary);
  background: var(--surface);
  border: 1px solid var(--line);
}

.app-meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  max-width: 560px;
  margin: 34px 0 0;
}

.app-meta div {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.app-meta dt {
  color: var(--muted);
  font-size: 13px;
}

.app-meta dd {
  margin: 4px 0 0;
  font-weight: 800;
  word-break: break-word;
}

.phone-preview {
  width: min(100%, 360px);
  margin: 0 auto;
  padding: 14px;
  border-radius: 34px;
  background: #102a31;
  box-shadow: var(--shadow);
}

.phone-top {
  width: 80px;
  height: 6px;
  margin: 4px auto 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.28);
}

.phone-screen {
  min-height: 560px;
  padding: 22px;
  border-radius: 24px;
  background: linear-gradient(180deg, #effafa, #ffffff 62%);
}

.app-row {
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: 14px;
}

.app-card {
  margin-top: 18px;
  padding: 18px;
  border-radius: 8px;
  background: var(--surface);
  border: 1px solid var(--line);
  font-weight: 700;
}

.app-card.target {
  color: var(--primary-dark);
  background: var(--surface-soft);
}

.listen-button {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 112px;
  width: 112px;
  margin: 56px auto 24px;
  border-radius: 50%;
  color: #fff;
  background: var(--primary);
  font-weight: 800;
  box-shadow: 0 18px 40px rgba(0, 122, 130, 0.28);
}

.mini-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}

.mini-grid span {
  padding: 12px;
  border-radius: 8px;
  text-align: center;
  color: var(--primary);
  border: 1px solid var(--line);
  background: var(--surface);
  font-weight: 700;
}

.section {
  max-width: 1160px;
  margin: 0 auto;
  padding: 56px clamp(20px, 5vw, 72px);
}

.section-heading {
  max-width: 680px;
}

.section h2,
.doc-page h2 {
  margin: 0;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.18;
  letter-spacing: 0;
}

.section-heading p,
.split p,
.download-panel p,
.audience-grid p,
.contact-card p {
  color: var(--muted);
  font-size: 17px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-top: 26px;
}

.feature-grid article,
.download-panel,
.scenario-list {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.feature-grid article {
  padding: 22px;
}

.feature-grid h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

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

.split {
  display: grid;
  grid-template-columns: 0.8fr 1fr;
  gap: 24px;
  align-items: start;
}

.scenario-list {
  margin: 0;
  padding: 24px 24px 24px 44px;
  color: var(--muted);
}

.scenario-list li + li {
  margin-top: 10px;
}

.audience-section {
  padding-top: 64px;
}

.audience-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-top: 28px;
}

.audience-grid article {
  min-height: 250px;
  padding: 24px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--surface);
}

.audience-grid span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 8px;
  color: var(--primary-dark);
  background: var(--surface-soft);
  font-weight: 900;
}

.audience-grid h3 {
  margin: 20px 0 10px;
  font-size: 22px;
}

.audience-grid p {
  margin: 0;
}

.download-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.72fr);
  gap: 28px;
  align-items: center;
  padding: 34px;
  background: linear-gradient(135deg, #ffffff, #e9f8f5);
}

.download-panel p {
  margin-bottom: 0;
}

.contact-card {
  padding: 24px;
  border-radius: 8px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
}

.contact-card span {
  display: block;
  color: rgba(255, 255, 255, 0.76);
  font-weight: 800;
}

.contact-card strong {
  display: block;
  margin-top: 8px;
  font-size: clamp(24px, 3vw, 32px);
  line-height: 1.15;
}

.contact-card p {
  margin: 12px 0 0;
  color: rgba(255, 255, 255, 0.82);
}

.light-link {
  display: inline-flex;
  margin-top: 16px;
  color: #fff;
  font-weight: 800;
  border-bottom: 1px solid rgba(255, 255, 255, 0.62);
}

.light-link:hover {
  color: #fff;
}

.floating-contact {
  position: fixed;
  right: clamp(16px, 3vw, 34px);
  bottom: clamp(16px, 3vw, 34px);
  z-index: 20;
  width: min(300px, calc(100vw - 32px));
  padding: 16px;
  border: 1px solid rgba(0, 122, 130, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 16px 44px rgba(17, 28, 34, 0.16);
  backdrop-filter: blur(14px);
}

.floating-contact span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}

.floating-contact strong {
  display: block;
  margin-top: 4px;
  color: var(--primary-dark);
  font-size: 18px;
}

.floating-contact p {
  margin: 4px 0 6px;
  color: var(--muted);
}

.floating-contact a {
  font-weight: 800;
  word-break: break-word;
}

.doc-page {
  max-width: 880px;
  margin: 0 auto;
  padding: 56px clamp(20px, 5vw, 72px);
}

.doc-page h1 {
  font-size: clamp(38px, 6vw, 64px);
}

.doc-date {
  color: var(--muted);
  margin: 12px 0 34px;
}

.doc-page section {
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.doc-page h2 {
  font-size: 24px;
}

.doc-page p,
.doc-page li {
  color: var(--muted);
}

.notice-panel {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.notice-panel .primary-button {
  margin-top: 12px;
}

.info-list {
  display: grid;
  gap: 12px;
  margin: 18px 0 0;
}

.info-list div {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 14px;
  padding: 14px 0;
  border-top: 1px solid var(--line);
}

.info-list dt {
  color: var(--muted);
}

.info-list dd {
  margin: 0;
  font-weight: 800;
}

.contact-methods {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.contact-methods article {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.contact-methods span {
  color: var(--muted);
  font-weight: 800;
}

.contact-methods strong {
  display: block;
  margin-top: 8px;
  font-size: 24px;
  word-break: break-word;
}

.contact-methods p {
  margin-bottom: 0;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
  max-width: 1160px;
  margin: 0 auto;
  padding: 28px clamp(20px, 5vw, 72px) 42px;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.site-footer span:last-child {
  display: flex;
  gap: 18px;
}

@media (max-width: 860px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero,
  .split,
  .download-panel {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 560px) {
  .site-nav {
    width: 100%;
    justify-content: space-between;
  }

  .hero {
    padding-top: 36px;
  }

  .app-meta,
  .feature-grid,
  .audience-grid,
  .contact-methods {
    grid-template-columns: 1fr;
  }

  .info-list div {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .audience-grid article {
    min-height: auto;
  }

  .phone-screen {
    min-height: 500px;
  }

  .primary-button,
  .secondary-button {
    width: 100%;
  }

  .floating-contact {
    position: static;
    width: auto;
    margin: 0 20px 24px;
  }
}