:root {
  color-scheme: light;
  --sky: #007cd6;
  --sky-deep: #045f9f;
  --sky-bright: #20a8ee;
  --sky-soft: #eaf8ff;
  --sky-wash: #f6fcff;
  --yellow: #ffcc66;
  --yellow-soft: #fff5cc;
  --ink: #0b3f66;
  --ink-2: #315c78;
  --muted: #6f8a9f;
  --white: #ffffff;
  --line: rgba(0, 124, 214, 0.16);
  --line-soft: rgba(0, 124, 214, 0.09);
  --shadow: 0 24px 70px rgba(18, 94, 150, 0.14);
  --shadow-soft: 0 14px 36px rgba(18, 94, 150, 0.1);
  --radius: 22px;
  font-family: "Noto Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: #ffffff;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(180deg, #f7fcff 0, #ffffff 680px, #ffffff 100%),
    #ffffff;
  letter-spacing: 0;
  overflow-x: hidden;
}

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

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

.intro-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(18px, 4vw, 58px);
  background: rgba(248, 253, 255, 0.88);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 900;
  white-space: nowrap;
}

.brand-sign {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 11px;
  color: var(--white);
  background: linear-gradient(135deg, var(--sky), var(--sky-bright));
  box-shadow: 0 10px 22px rgba(0, 124, 214, 0.2);
  font-size: 13px;
  font-weight: 900;
}

.intro-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.intro-nav a {
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--ink-2);
  font-size: 14px;
  font-weight: 800;
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.intro-nav a:hover,
.intro-nav a:focus-visible,
.intro-nav a.is-active {
  color: var(--sky);
  background: var(--white);
  outline: none;
  box-shadow: 0 10px 24px rgba(0, 124, 214, 0.09);
}

.intro-nav .nav-demo {
  color: var(--white);
  background: var(--sky-deep);
  box-shadow: 0 12px 26px rgba(0, 124, 214, 0.2);
}

main {
  width: 100%;
}

section {
  padding: 92px clamp(22px, 5vw, 76px);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.98fr) minmax(430px, 1.02fr);
  gap: clamp(34px, 5vw, 76px);
  align-items: center;
  min-height: 96svh;
  padding-top: 120px;
  background:
    radial-gradient(circle at 78% 22%, rgba(255, 204, 102, 0.2), transparent 28%),
    linear-gradient(135deg, #ffffff 0%, #f3fbff 66%, #fff7db 100%);
}

.hero-copy {
  max-width: 850px;
}

.eyebrow,
.section-kicker,
.feature-label {
  margin: 0;
  color: var(--sky);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1,
.section-heading h2,
.story-layout h2,
.crowd-copy h2,
.codex-card h2,
.cta-section h2 {
  margin: 0;
  color: var(--ink);
  line-height: 1.04;
  font-weight: 900;
}

.hero h1 {
  max-width: 800px;
  margin-top: 14px;
  font-size: clamp(46px, 7vw, 92px);
}

.hero-lead {
  max-width: 760px;
  margin: 24px 0 0;
  color: var(--ink-2);
  font-size: clamp(17px, 1.7vw, 21px);
  line-height: 1.78;
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 54px;
  padding: 0 24px;
  border-radius: 999px;
  font-weight: 900;
  transition: transform 0.22s ease, box-shadow 0.22s ease, background 0.22s ease;
}

.btn:hover,
.btn:focus-visible {
  transform: translateY(-2px);
  outline: none;
}

.btn.primary {
  color: var(--white);
  background: linear-gradient(135deg, var(--sky-deep), var(--sky));
  box-shadow: 0 18px 36px rgba(0, 92, 160, 0.3);
}

.btn.primary:hover,
.btn.primary:focus-visible {
  box-shadow: 0 24px 48px rgba(0, 92, 160, 0.36);
}

.btn.large {
  min-height: 58px;
  padding: 0 28px;
}

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

.hero-tags span {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  color: var(--sky-deep);
  background: rgba(255, 255, 255, 0.72);
  box-shadow: inset 0 0 0 1px rgba(0, 124, 214, 0.14);
  font-size: 13px;
  font-weight: 900;
}

.hero-panel {
  align-self: center;
  overflow: hidden;
  border-radius: 30px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: var(--shadow);
  animation: float-panel 5.4s ease-in-out infinite;
}

.panel-caption {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 20px;
  color: var(--ink-2);
  background: rgba(255, 255, 255, 0.92);
}

.panel-caption span,
.panel-caption strong {
  font-size: 13px;
  font-weight: 900;
}

.panel-caption span {
  color: var(--sky);
}

.hero-panel img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: top left;
  filter: contrast(1.08) saturate(1.08);
}

.section-reveal {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.72s ease, transform 0.72s ease;
}

.motion-ready .section-reveal:not(.hero) {
  opacity: 1;
  transform: translateY(16px);
}

.motion-ready .section-reveal.is-visible,
.motion-ready .hero.section-reveal {
  opacity: 1;
  transform: translateY(0);
}

.story-section {
  background: linear-gradient(180deg, #ffffff 0%, #f7fcff 100%);
}

.section-kicker {
  margin-bottom: 18px;
}

.story-layout,
.crowd-section,
.codex-card {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(360px, 1.1fr);
  gap: clamp(28px, 5vw, 70px);
  align-items: center;
}

.story-layout h2,
.section-heading h2,
.crowd-copy h2,
.codex-card h2,
.cta-section h2 {
  font-size: clamp(32px, 4.8vw, 58px);
}

.story-layout p,
.section-heading p,
.demo-copy p,
.crowd-copy p,
.codex-card p,
.cta-section p,
.phone-result p {
  color: var(--ink-2);
  line-height: 1.78;
}

.problem-layers {
  display: grid;
  gap: 12px;
}

.problem-layers article {
  display: grid;
  grid-template-columns: 58px minmax(120px, 0.42fr) 1fr;
  gap: 16px;
  align-items: center;
  min-height: 96px;
  padding: 18px 20px;
  border-radius: 22px;
  background: var(--layer-bg);
  box-shadow: var(--shadow-soft);
  transform: translateX(var(--offset));
}

.problem-layers article:nth-child(1) {
  --layer-bg: #f7fcff;
  --offset: 0;
}

.problem-layers article:nth-child(2) {
  --layer-bg: #edf8ff;
  --offset: 18px;
}

.problem-layers article:nth-child(3) {
  --layer-bg: #ddf2ff;
  --offset: 36px;
}

.problem-layers article:nth-child(4) {
  --layer-bg: #ccecff;
  --offset: 54px;
}

.problem-layers span {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 16px;
  color: var(--white);
  background: linear-gradient(135deg, var(--sky-deep), var(--sky));
  font-weight: 900;
}

.problem-layers strong {
  color: var(--ink);
  font-size: 18px;
}

.problem-layers p {
  margin: 0;
  color: var(--ink-2);
  line-height: 1.55;
}

.thinking-section {
  background: linear-gradient(180deg, #f7fcff 0%, #ffffff 100%);
}

.section-heading {
  max-width: 920px;
  margin-bottom: 34px;
}

.flow-track {
  --progress: 0%;
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
}

.flow-track::before,
.flow-track::after {
  content: "";
  position: absolute;
  left: 6%;
  right: 6%;
  top: 38px;
  height: 4px;
  border-radius: 999px;
}

.flow-track::before {
  background: rgba(0, 124, 214, 0.12);
}

.flow-track::after {
  right: auto;
  width: var(--progress);
  max-width: 88%;
  background: linear-gradient(90deg, var(--sky-deep), var(--sky-bright));
  transition: width 0.55s ease;
}

.flow-track.is-visible {
  animation: track-progress 5.8s ease-in-out infinite;
}

.flow-step {
  position: relative;
  z-index: 1;
  min-height: 220px;
  padding: 20px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.78);
  box-shadow: var(--shadow-soft);
  transition: transform 0.32s ease, box-shadow 0.32s ease, background 0.32s ease;
}

.flow-step span {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 16px;
  color: var(--sky);
  background: var(--sky-soft);
  font-weight: 900;
  transition: background 0.32s ease, color 0.32s ease, transform 0.32s ease;
}

.flow-step h3 {
  margin: 18px 0 8px;
  color: var(--ink);
  font-size: 24px;
}

.flow-step p {
  margin: 0;
  color: var(--ink-2);
  line-height: 1.72;
}

.flow-step.is-active {
  transform: translateY(-8px);
  background: #ffffff;
  box-shadow: var(--shadow);
}

.flow-step.is-active span {
  color: #ffffff;
  background: linear-gradient(135deg, var(--sky-deep), var(--sky));
  transform: scale(1.08);
}

.feature-section {
  background: linear-gradient(180deg, #ffffff 0%, #f7fcff 48%, #ffffff 100%);
}

.demo-gallery {
  display: grid;
  gap: 28px;
}

.demo-card {
  display: grid;
  grid-template-columns: minmax(0, 1.18fr) minmax(300px, 0.82fr);
  gap: clamp(22px, 3vw, 40px);
  align-items: center;
  padding: clamp(18px, 2vw, 28px);
  border-radius: 30px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: var(--shadow-soft);
}

.demo-card:nth-child(even) {
  grid-template-columns: minmax(300px, 0.82fr) minmax(0, 1.18fr);
}

.demo-card:nth-child(even) .demo-shot {
  order: 2;
}

.demo-card.featured {
  background: linear-gradient(135deg, #ffffff, #eef9ff);
}

.demo-shot {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: 22px;
  background: var(--sky-soft);
  box-shadow: 0 18px 44px rgba(18, 94, 150, 0.12);
}

.demo-shot::after {
  content: "点击进入模块";
  position: absolute;
  right: 16px;
  bottom: 16px;
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--white);
  background: rgba(4, 95, 159, 0.86);
  font-size: 12px;
  font-weight: 900;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.22s ease, transform 0.22s ease;
}

.demo-shot:hover::after,
.demo-shot:focus-visible::after {
  opacity: 1;
  transform: translateY(0);
}

.demo-shot img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: top left;
  transition: transform 0.35s ease;
}

.demo-shot:hover img,
.demo-shot:focus-visible img {
  transform: scale(1.025);
}

.demo-copy {
  padding: 6px;
}

.demo-copy h3 {
  margin: 12px 0 12px;
  color: var(--ink);
  font-size: clamp(24px, 2.6vw, 36px);
  line-height: 1.2;
}

.module-link {
  display: inline-flex;
  align-items: center;
  margin-top: 12px;
  color: var(--sky-deep);
  font-weight: 900;
}

.module-link::after {
  content: "→";
  margin-left: 8px;
  transition: transform 0.2s ease;
}

.module-link:hover::after,
.module-link:focus-visible::after {
  transform: translateX(4px);
}

.crowd-section {
  background: linear-gradient(135deg, #f7fcff, #ffffff 52%, #fff8df);
}

.reward-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.reward-strip span {
  display: inline-flex;
  align-items: center;
  min-height: 38px;
  padding: 0 13px;
  border-radius: 999px;
  color: var(--sky-deep);
  background: rgba(255, 255, 255, 0.72);
  box-shadow: inset 0 0 0 1px rgba(0, 124, 214, 0.13);
  font-weight: 900;
}

.reward-strip strong {
  margin-right: 5px;
  color: var(--sky);
  font-size: 22px;
}

.crowd-link {
  margin-top: 22px;
}

.phone-demo {
  display: flex;
  justify-content: center;
}

.phone-frame {
  width: min(360px, 100%);
  padding: 14px;
  border-radius: 36px;
  background: #f3fbff;
  box-shadow: var(--shadow);
}

.phone-top {
  width: 110px;
  height: 24px;
  margin: -14px auto 10px;
  border-radius: 0 0 15px 15px;
  background: #d6ebf8;
}

.phone-screen {
  min-height: 580px;
  overflow: hidden;
  border-radius: 24px;
  background: var(--white);
}

.phone-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 18px;
  color: var(--white);
  background: var(--sky);
  font-weight: 900;
}

.phone-head b {
  padding: 4px 9px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.2);
  font-size: 12px;
}

.phone-photo {
  position: relative;
  height: 230px;
  overflow: hidden;
}

.phone-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.scan-line {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--sky), transparent);
  box-shadow: 0 0 18px rgba(0, 124, 214, 0.6);
  animation: scan 2.8s ease-in-out infinite;
}

.phone-tag {
  position: absolute;
  left: 18px;
  bottom: 18px;
  padding: 6px 10px;
  border-radius: 999px;
  color: var(--white);
  background: rgba(0, 124, 214, 0.84);
  font-size: 12px;
  font-weight: 900;
}

.phone-result {
  margin: 18px;
  padding: 16px;
  border-radius: 16px;
  background: var(--sky-soft);
}

.phone-result span {
  color: var(--sky);
  font-weight: 900;
}

.phone-result strong {
  display: block;
  margin: 8px 0;
  color: var(--ink);
  font-size: 22px;
}

.codex-section {
  background: #ffffff;
}

.codex-card {
  padding: clamp(24px, 4vw, 42px);
  border-radius: 30px;
  background: linear-gradient(135deg, #ffffff, #edf8ff 62%, #fff5d6);
  box-shadow: var(--shadow);
}

.build-stack {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.build-stack span {
  display: grid;
  place-items: center;
  min-height: 92px;
  border-radius: 18px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.72);
  font-size: 18px;
  font-weight: 900;
}

.build-stack span:nth-child(4) {
  color: var(--white);
  background: var(--sky);
}

.cta-section {
  min-height: 58svh;
  display: grid;
  place-items: center;
  text-align: center;
  background:
    radial-gradient(circle at 50% 20%, rgba(255, 204, 102, 0.22), transparent 30%),
    linear-gradient(180deg, #f6fcff, #ffffff);
}

.cta-section p {
  max-width: 720px;
  margin: 18px auto 28px;
  font-size: 18px;
}

@keyframes scan {
  0% { top: 0; opacity: 0; }
  12% { opacity: 1; }
  72% { top: 100%; opacity: 0.9; }
  100% { top: 100%; opacity: 0; }
}

@keyframes float-panel {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

@keyframes track-progress {
  0%, 10% { --progress: 0%; }
  24% { --progress: 22%; }
  38% { --progress: 44%; }
  52% { --progress: 66%; }
  66%, 100% { --progress: 88%; }
}

@media (max-width: 1120px) {
  .hero,
  .story-layout,
  .crowd-section,
  .codex-card {
    grid-template-columns: 1fr;
  }

  .problem-layers article {
    transform: none;
  }

  .flow-track {
    grid-template-columns: 1fr;
  }

  .flow-track::before,
  .flow-track::after {
    display: none;
  }

  .demo-card,
  .demo-card:nth-child(even) {
    grid-template-columns: 1fr;
  }

  .demo-card:nth-child(even) .demo-shot {
    order: 0;
  }
}

@media (max-width: 760px) {
  .intro-header {
    position: sticky;
    padding: 12px 16px;
  }

  .intro-nav {
    display: none;
  }

  section,
  .hero {
    padding-left: 18px;
    padding-right: 18px;
  }

  .hero {
    min-height: auto;
    padding-top: 72px;
    padding-bottom: 52px;
  }

  .hero h1 {
    font-size: 42px;
  }

  .hero-tags,
  .reward-strip {
    align-items: stretch;
    flex-direction: column;
  }

  .hero-tags span,
  .reward-strip span,
  .btn {
    width: 100%;
  }

  .panel-caption {
    flex-direction: column;
    gap: 4px;
  }

  .problem-layers article {
    grid-template-columns: 48px 1fr;
  }

  .problem-layers p {
    grid-column: 1 / -1;
  }

  .build-stack {
    grid-template-columns: 1fr 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}