:root {
  --bg: #f7f8fb;
  --paper: #ffffff;
  --text: #15171c;
  --muted: #626a78;
  --line: #e7e9ee;
  --blue: #1769ff;
  --blue-deep: #0b4ed8;
  --ink: #111827;
  --soft: #eef4ff;
  --shadow: 0 28px 80px rgba(16, 24, 40, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Microsoft YaHei UI", "Segoe UI", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  letter-spacing: 0;
}

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

button,
input,
textarea,
.button {
  font: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  padding: 0 56px;
  background: rgba(247, 248, 251, 0.88);
  border-bottom: 1px solid rgba(231, 233, 238, 0.76);
  backdrop-filter: blur(18px);
}

.brand,
.site-nav,
.hero-actions,
.visual-head,
.site-footer,
.modal-actions {
  display: flex;
  align-items: center;
}

.brand {
  gap: 11px;
  font-weight: 900;
}

.brand-icon {
  width: 34px;
  height: 34px;
}

.brand span {
  font-size: 20px;
}

.brand em {
  color: var(--muted);
  font-size: 13px;
  font-style: normal;
  font-weight: 700;
}

.site-nav {
  gap: 34px;
  color: #303846;
  font-size: 15px;
}

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

.nav-action {
  min-height: 42px;
  padding: 0 18px;
  background: var(--text);
  border: 0;
  border-radius: 999px;
  color: #fff;
  cursor: pointer;
  font-weight: 800;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(420px, 1.08fr);
  gap: 72px;
  align-items: center;
  min-height: calc(100vh - 76px);
  padding: 74px 64px 56px;
}

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

.eyebrow {
  margin: 0 0 16px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 900;
}

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

h1 {
  margin-bottom: 22px;
  font-size: clamp(72px, 10vw, 156px);
  line-height: 0.86;
  font-weight: 950;
}

.slogan {
  margin-bottom: 22px;
  font-size: clamp(30px, 4vw, 58px);
  line-height: 1.08;
  font-weight: 950;
}

.hero-text,
.statement p,
.feature-lines p,
.plain-list,
.formats p,
.blog-card p,
.download-section p,
.modal-panel p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.86;
}

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

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 24px;
  border: 1px solid var(--line);
  border-radius: 999px;
  cursor: pointer;
  font-weight: 900;
}

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

.button.primary:hover {
  background: var(--blue-deep);
  border-color: var(--blue-deep);
}

.button.secondary {
  background: var(--paper);
}

.support-note {
  margin-top: 16px;
  color: var(--muted);
  font-size: 14px;
}

.product-visual {
  min-width: 0;
}

.visual-screen {
  position: relative;
  overflow: hidden;
  padding: 24px;
  background:
    radial-gradient(circle at 72% 18%, rgba(23, 105, 255, 0.18), transparent 28%),
    linear-gradient(145deg, #ffffff, #eef3fb);
  border: 1px solid var(--line);
  border-radius: 30px;
  box-shadow: var(--shadow);
}

.visual-head {
  justify-content: space-between;
  margin-bottom: 18px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
}

.visual-head strong {
  color: var(--text);
}

.visual-player {
  position: relative;
  min-height: 330px;
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.12), transparent 42%),
    linear-gradient(145deg, #141b28, #2a405e 58%, #111827);
  border-radius: 24px;
}

.visual-player::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 42%;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.45));
}

.play-mark {
  position: absolute;
  left: 50%;
  top: 50%;
  z-index: 1;
  width: 72px;
  height: 72px;
  transform: translate(-50%, -50%);
  background: rgba(255, 255, 255, 0.92);
  border-radius: 50%;
}

.play-mark::after {
  content: "";
  position: absolute;
  left: 29px;
  top: 21px;
  border-left: 22px solid var(--blue);
  border-top: 15px solid transparent;
  border-bottom: 15px solid transparent;
}

.visual-timeline {
  position: relative;
  height: 42px;
  margin: 18px 4px 14px;
  border-bottom: 3px solid #d7deea;
}

.visual-timeline i {
  position: absolute;
  left: var(--left);
  bottom: -3px;
  width: var(--width);
  height: 8px;
  background: var(--blue);
  border-radius: 999px;
}

.visual-notes {
  display: grid;
  gap: 10px;
}

.visual-notes button {
  min-height: 46px;
  padding: 0 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  color: #2b3341;
  text-align: left;
  font-weight: 800;
}

.statement {
  padding: 0 64px 88px;
}

.statement p {
  max-width: 1180px;
  margin: 0 auto;
  padding: 44px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  color: #303846;
  font-size: clamp(22px, 3vw, 38px);
  line-height: 1.48;
  font-weight: 850;
}

.feature-flow,
.use-section,
.formats,
.blog-section,
.download-section {
  padding: 96px 64px;
}

.feature-flow {
  display: grid;
  grid-template-columns: minmax(260px, 0.78fr) minmax(460px, 1.22fr);
  gap: 80px;
  background: var(--paper);
}

.feature-copy h2,
.use-section h2,
.formats h2,
.section-title h2,
.download-section h2 {
  margin-bottom: 0;
  font-size: clamp(34px, 4.6vw, 64px);
  line-height: 1.08;
}

.feature-lines article {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 24px;
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.feature-lines article:first-child {
  padding-top: 0;
}

.feature-lines span {
  color: var(--blue);
  font-weight: 950;
}

.feature-lines h3 {
  margin-bottom: 8px;
  font-size: 25px;
}

.use-section {
  display: grid;
  grid-template-columns: minmax(260px, 0.86fr) minmax(460px, 1.14fr);
  gap: 72px;
}

.plain-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.plain-list li {
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
  color: #222936;
  font-size: 22px;
  font-weight: 800;
}

.formats {
  background: var(--paper);
}

.formats p {
  max-width: 980px;
  margin-top: 24px;
  color: #303846;
  font-size: 21px;
}

.blog-section {
  background: #f7f8fb;
}

.section-title {
  margin-bottom: 32px;
}

.blog-list {
  display: grid;
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--line);
}

.blog-card {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 36px;
  padding: 30px;
  background: var(--paper);
}

.blog-card time {
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
}

.blog-card h3 {
  margin-bottom: 10px;
  font-size: 26px;
}

.download-section {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 52px;
  background: #101722;
  color: #fff;
}

.download-section > div {
  max-width: 760px;
}

.download-section p {
  margin-top: 18px;
  color: #cbd5e1;
}

.download-section .eyebrow {
  color: #8bb8ff;
}

.button.light {
  flex: 0 0 auto;
  background: #fff;
  border-color: #fff;
  color: var(--text);
}

.site-footer {
  justify-content: space-between;
  min-height: 82px;
  padding: 0 64px;
  background: #fff;
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.site-footer span {
  color: var(--text);
  font-weight: 950;
}

.sponsor-modal[hidden] {
  display: none;
}

.sponsor-modal {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(9, 14, 23, 0.56);
}

.modal-panel {
  position: relative;
  width: min(680px, 100%);
  padding: 36px;
  background: #fff;
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.modal-close {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 38px;
  height: 38px;
  background: #f2f4f7;
  border: 0;
  border-radius: 50%;
  cursor: pointer;
  font-size: 24px;
}

.qr-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin: 24px 0;
}

.qr-card {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  text-align: center;
}

.qr-card img {
  display: block;
  width: 100%;
  max-width: 220px;
  margin: 0 auto 12px;
  border-radius: 12px;
}

.qr-card strong {
  display: block;
}

@media (max-width: 980px) {
  .site-header {
    padding: 0 24px;
  }

  .site-nav {
    display: none;
  }

  .hero,
  .feature-flow,
  .use-section {
    grid-template-columns: 1fr;
  }

  .hero,
  .feature-flow,
  .use-section,
  .formats,
  .blog-section,
  .download-section {
    padding-left: 24px;
    padding-right: 24px;
  }

  .statement {
    padding-left: 24px;
    padding-right: 24px;
  }
}

@media (max-width: 680px) {
  .nav-action {
    display: none;
  }

  .hero {
    padding-top: 54px;
  }

  .hero-actions .button,
  .download-section .button {
    width: 100%;
  }

  .visual-player {
    min-height: 230px;
  }

  .feature-lines article,
  .blog-card,
  .download-section {
    grid-template-columns: 1fr;
  }

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

  .site-footer {
    justify-content: center;
    padding: 24px;
  }

  .qr-grid {
    grid-template-columns: 1fr;
  }
}