:root {
  --bg: #f6f8fb;
  --panel: #ffffff;
  --ink: #151922;
  --muted: #5f6b7a;
  --line: #dde5ef;
  --blue: #0a7cff;
  --blue-dark: #075dc2;
  --red: #d82136;
  --yellow: #f7a71a;
  --green: #68d65f;
  --shadow: 0 16px 44px rgba(25, 45, 75, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: 72px;
  padding: 0 clamp(20px, 5vw, 72px);
  border-bottom: 1px solid rgba(221, 229, 239, 0.72);
  background: rgba(246, 248, 251, 0.9);
  backdrop-filter: blur(18px);
}

.site-header.is-scrolled {
  box-shadow: 0 10px 30px rgba(25, 45, 75, 0.08);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 20px;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  color: #fff;
  background: var(--blue);
  font-size: 18px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 28px;
  color: var(--muted);
  font-size: 15px;
}

.nav a:hover,
.header-action:hover {
  color: var(--blue);
}

.header-action {
  padding: 10px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-weight: 700;
  background: #fff;
}

.hero {
  min-height: calc(100vh - 72px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 520px);
  align-items: center;
  gap: clamp(30px, 6vw, 84px);
  padding: clamp(36px, 6vw, 76px) clamp(20px, 7vw, 92px) 54px;
  background: linear-gradient(180deg, #edf7ff 0%, #f6f8fb 88%);
}

.hero-copy {
  max-width: 680px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 18px;
  font-size: clamp(56px, 7vw, 96px);
  line-height: 1;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 16px;
  font-size: clamp(30px, 4vw, 54px);
  line-height: 1.12;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  font-size: 22px;
  letter-spacing: 0;
}

.hero-text,
.screen-copy p,
.wear-copy p,
.download p {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 32px 0;
}

.primary-btn,
.secondary-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border-radius: 8px;
  font-weight: 800;
}

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

.primary-btn:hover {
  background: var(--blue-dark);
}

.secondary-btn {
  border: 1px solid var(--line);
  background: #fff;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin: 0;
}

.hero-stats div {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.78);
}

.hero-stats dt {
  font-size: 28px;
  font-weight: 900;
}

.hero-stats dd {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.hero-media {
  justify-self: center;
  width: min(100%, 410px);
}

.hero-media img {
  width: 100%;
  max-height: 76vh;
  object-fit: cover;
  object-position: top;
  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.section {
  padding: 86px clamp(20px, 7vw, 92px);
}

.intro-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  padding-top: 0;
  padding-bottom: 0;
  background: var(--line);
}

.strip-item {
  min-height: 118px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 8px;
  padding: 26px;
  background: #fff;
}

.strip-item strong {
  font-size: 20px;
}

.strip-item span,
.feature-card p,
.privacy-list span,
.watch-preview span {
  color: var(--muted);
  line-height: 1.7;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 32px;
}

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

.feature-card {
  min-height: 260px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.feature-index {
  display: inline-block;
  margin-bottom: 42px;
  color: var(--blue);
  font-weight: 900;
}

.screens {
  display: grid;
  grid-template-columns: 0.86fr 1.14fr;
  align-items: center;
  gap: clamp(28px, 6vw, 72px);
  background: #fff;
}

.screen-copy {
  max-width: 560px;
}

.screen-gallery {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.screen-gallery figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: #f2f7fd;
  box-shadow: 0 14px 38px rgba(25, 45, 75, 0.1);
}

.screen-gallery img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.screen-gallery figcaption {
  padding: 12px 14px;
  color: var(--muted);
  font-weight: 700;
  background: #fff;
}

.wear-section {
  display: grid;
  grid-template-columns: minmax(280px, 520px) minmax(0, 1fr);
  gap: clamp(28px, 6vw, 76px);
  align-items: center;
  padding: 86px clamp(20px, 7vw, 92px);
  background: #f5f1e8;
}

.wear-image img {
  width: 100%;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.wear-copy {
  max-width: 620px;
}

.watch-preview {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-top: 30px;
  padding: 16px;
  border: 1px solid rgba(21, 25, 34, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.72);
}

.watch-preview img {
  width: 96px;
  border-radius: 8px;
}

.watch-preview strong,
.watch-preview span {
  display: block;
}

.privacy {
  background: #fff;
}

.privacy-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.privacy-list div {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfe;
}

.privacy-list strong {
  display: block;
  margin-bottom: 10px;
  font-size: 20px;
}

.download {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin: 0 clamp(20px, 7vw, 92px) 70px;
  padding: 36px;
  border-radius: 8px;
  color: #fff;
  background: #151922;
}

.download p {
  max-width: 760px;
  margin-bottom: 0;
  color: #ccd6e2;
}

.download .eyebrow {
  color: #73b8ff;
}

.download .primary-btn {
  flex: 0 0 auto;
}

.footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 28px clamp(20px, 7vw, 92px);
  border-top: 1px solid var(--line);
  color: var(--muted);
  background: #fff;
}

@media (max-width: 980px) {
  .site-header {
    height: auto;
    min-height: 66px;
  }

  .nav {
    display: none;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-media {
    width: min(100%, 360px);
  }

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

  .screens,
  .wear-section {
    grid-template-columns: 1fr;
  }

  .wear-image {
    max-width: 520px;
  }
}

@media (max-width: 680px) {
  .site-header {
    padding: 12px 18px;
  }

  .header-action {
    display: none;
  }

  .hero {
    padding: 30px 18px 42px;
  }

  .hero-stats,
  .intro-strip,
  .feature-grid,
  .privacy-list {
    grid-template-columns: 1fr;
  }

  .section,
  .wear-section {
    padding: 58px 18px;
  }

  .screen-gallery {
    grid-template-columns: 1fr;
  }

  .screen-gallery figure:nth-child(2) {
    display: none;
  }

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

  .download {
    margin: 0 18px 44px;
    padding: 26px;
  }
}