:root {
  color-scheme: dark;
  --bg: #071527;
  --bg-deep: #04101e;
  --text: #f7fbff;
  --muted: rgba(230, 242, 255, 0.78);
  --soft: rgba(230, 242, 255, 0.58);
  --line: rgba(255, 255, 255, 0.16);
  --line-strong: rgba(255, 255, 255, 0.24);
  --panel: rgba(7, 22, 40, 0.42);
  --panel-strong: rgba(7, 22, 40, 0.58);
  --blue: #5db8ff;
  --cyan: #7fe9ff;
  --oxygen: #ff9f3f;
  --oxygen-deep: #ff6d28;
  --green: #67e8a5;
  --shadow: 0 28px 90px rgba(0, 20, 48, 0.42);
  --radius-xl: 34px;
  --radius-lg: 26px;
  --radius-md: 18px;
  --page-bg: url('/assets/qinghai-chat-hd.jpg');
  --page-bg-position: center 46%;
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 10% 12%, rgba(93, 184, 255, 0.18), transparent 30%),
    linear-gradient(180deg, #071a31 0%, var(--bg) 48%, #08213c 100%);
  color: var(--text);
  overflow-x: hidden;
}

a { color: inherit; }

.page-shell {
  position: relative;
  isolation: isolate;
  min-height: 100vh;
}

.page-shell::before {
  content: '';
  position: absolute;
  inset: 0 0 auto;
  height: min(980px, 100vh + 180px);
  z-index: -3;
  background:
    linear-gradient(90deg, rgba(7, 26, 49, 0.44) 0%, rgba(7, 26, 49, 0.16) 42%, rgba(7, 26, 49, 0.34) 100%),
    linear-gradient(180deg, rgba(9, 28, 52, 0.08) 0%, rgba(9, 28, 52, 0.14) 38%, rgba(7, 20, 38, 0.5) 100%),
    var(--page-bg) var(--page-bg-position) / cover no-repeat;
}

.page-shell::after {
  content: '';
  position: absolute;
  inset: 0 0 auto;
  height: min(980px, 100vh + 180px);
  z-index: -2;
  background:
    radial-gradient(circle at 18% 20%, rgba(127, 233, 255, 0.1), transparent 30%),
    radial-gradient(circle at 82% 22%, rgba(255, 159, 63, 0.08), transparent 24%);
  pointer-events: none;
}

.aurora {
  position: absolute;
  inset: -20% -10% auto;
  height: 60vh;
  z-index: -1;
  background:
    radial-gradient(circle at 20% 40%, rgba(127, 233, 255, 0.12), transparent 22%),
    radial-gradient(circle at 70% 20%, rgba(255, 159, 63, 0.08), transparent 24%);
  filter: blur(10px);
  animation: floatGlow 14s ease-in-out infinite alternate;
  will-change: transform, opacity;
  transform: translateZ(0);
}

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto;
  padding: max(18px, env(safe-area-inset-top)) 20px 14px;
  transition: background 0.24s ease, box-shadow 0.24s ease, border-color 0.24s ease;
  border: 1px solid transparent;
  border-radius: 0 0 28px 28px;
}

.nav.is-scrolled {
  background: rgba(5, 18, 34, 0.62);
  border-color: rgba(255, 255, 255, 0.1);
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.22);
  backdrop-filter: blur(10px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(127, 233, 255, 0.35);
  border-radius: 15px;
  background: linear-gradient(145deg, rgba(93, 184, 255, 0.32), rgba(255, 159, 63, 0.16));
  box-shadow: 0 14px 34px rgba(14, 112, 255, 0.2);
  font-weight: 900;
  letter-spacing: -0.08em;
}

.brand-title {
  display: grid;
  gap: 2px;
}

.brand-title strong {
  font-size: 16px;
  letter-spacing: 0.08em;
}

.brand-title span {
  color: var(--soft);
  font-size: 11px;
  letter-spacing: 0.08em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 7px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(3, 16, 31, 0.22);
  box-shadow: 0 14px 38px rgba(0, 0, 0, 0.14);
  backdrop-filter: blur(8px);
}

.nav-links a {
  padding: 9px 13px;
  border-radius: 999px;
  color: var(--muted);
  font-size: 13px;
  text-decoration: none;
  transition: 0.2s ease;
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a[aria-current='page'] {
  color: var(--text);
  background: rgba(255, 255, 255, 0.08);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 0 17px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--oxygen), var(--oxygen-deep));
  color: #fff;
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
  box-shadow: 0 18px 42px rgba(255, 109, 40, 0.28);
  white-space: nowrap;
}

main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 34px 20px 72px;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(320px, 0.94fr);
  gap: 32px;
  align-items: center;
  min-height: calc(100vh - 130px);
  padding: 36px 0 58px;
}

.hero.compact {
  min-height: auto;
  padding: 44px 0 22px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  width: fit-content;
  padding: 9px 14px;
  border: 1px solid rgba(127, 233, 255, 0.32);
  border-radius: 999px;
  background: rgba(127, 233, 255, 0.1);
  color: #dff9ff;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.03em;
}

.pulse-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 0 rgba(103, 232, 165, 0.55);
  animation: pulse 1.8s infinite;
}

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

h1 {
  max-width: 760px;
  margin: 24px 0 18px;
  font-size: clamp(44px, 8vw, 86px);
  line-height: 0.95;
  letter-spacing: -0.075em;
  text-shadow: 0 10px 28px rgba(6, 20, 38, 0.22);
}

h2 {
  font-size: clamp(32px, 4vw, 50px);
  line-height: 1.02;
  letter-spacing: -0.05em;
}

.gradient-text {
  display: block;
  background: linear-gradient(90deg, #fff 8%, #bdeeff 46%, #ffce9f 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-copy,
.lead {
  max-width: 680px;
  color: var(--muted);
  font-size: clamp(16px, 2vw, 20px);
  line-height: 1.8;
  text-shadow: 0 8px 24px rgba(6, 20, 38, 0.22);
}

.hero-actions,
.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 54px;
  padding: 0 22px;
  border: 0;
  border-radius: 18px;
  font-size: 15px;
  font-weight: 900;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.button:hover { transform: translateY(-2px); }
.button:active { transform: translateY(0); }

.button.primary {
  color: #fff;
  background: linear-gradient(135deg, var(--oxygen), var(--oxygen-deep));
  box-shadow: 0 20px 46px rgba(255, 109, 40, 0.28);
}

.button.secondary {
  color: #e8f7ff;
  border: 1px solid rgba(127, 233, 255, 0.28);
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(8px);
}

.hero-meta,
.status-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 11px;
  margin-top: 26px;
  color: var(--soft);
  font-size: 13px;
}

.hero-meta span,
.status-pill {
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.07);
}

.status-pill.pending {
  border-color: rgba(255, 159, 63, 0.24);
  background: rgba(255, 159, 63, 0.09);
}

.hero-card,
.visual-card {
  position: relative;
  min-height: 620px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.16), rgba(255, 255, 255, 0.06)),
    rgba(6, 20, 38, 0.38);
  box-shadow: var(--shadow);
  overflow: hidden;
  backdrop-filter: blur(10px);
}

.hero-card::before,
.visual-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(3, 14, 28, 0.02) 6%, rgba(6, 20, 38, 0.12) 44%, rgba(6, 20, 38, 0.54) 100%),
    var(--card-bg, url('/assets/chat-landscape-hd.jpg')) center 44% / cover no-repeat;
  opacity: 0.98;
}

.radar {
  position: absolute;
  inset: 42px 42px auto auto;
  width: 190px;
  height: 190px;
  border: 1px solid rgba(127, 233, 255, 0.36);
  border-radius: 50%;
  background:
    radial-gradient(circle, transparent 0 22%, rgba(127, 233, 255, 0.12) 23% 24%, transparent 25% 48%, rgba(127, 233, 255, 0.14) 49% 50%, transparent 51%),
    conic-gradient(from 0deg, rgba(127, 233, 255, 0.54), transparent 30%, transparent);
  animation: rotate 8s linear infinite;
  opacity: 0.9;
  will-change: transform;
  transform: translateZ(0);
}

.device {
  position: absolute;
  left: 34px;
  right: 34px;
  bottom: 34px;
  display: grid;
  gap: 15px;
  padding: 20px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 24px;
  background: rgba(9, 24, 44, 0.92);
  box-shadow: 0 18px 46px rgba(0, 0, 0, 0.26);
  backdrop-filter: blur(12px);
}

.device-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.avatar {
  display: flex;
  align-items: center;
  gap: 12px;
}

.avatar img {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
}

.avatar strong {
  display: block;
  margin-bottom: 3px;
  font-size: 14px;
}

.avatar span,
.mini-copy {
  color: var(--soft);
  font-size: 12px;
  line-height: 1.55;
}

.live-pill {
  flex-shrink: 0;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(103, 232, 165, 0.14);
  color: #b7ffd7;
  font-size: 12px;
  font-weight: 800;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.metric {
  padding: 14px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
}

.metric span {
  display: block;
  color: var(--soft);
  font-size: 12px;
  margin-bottom: 8px;
}

.metric strong {
  font-size: 18px;
}

.oxygen-bar {
  height: 10px;
  border-radius: 999px;
  background: linear-gradient(90deg, rgba(93, 184, 255, 0.9), rgba(255, 159, 63, 0.9));
}

.section {
  margin-top: 48px;
}

.section-card,
.download-panel,
.grid-card,
.list-item,
.page-nav a {
  border: 1px solid var(--line);
  background: rgba(7, 22, 40, 0.56);
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
}

.section-card,
.download-panel {
  padding: 32px;
  border-radius: var(--radius-xl);
}

.grid {
  display: grid;
  gap: 18px;
}

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

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

.grid-card {
  padding: 24px;
  border-radius: 24px;
}

.grid-card h3,
.list-item h3 {
  margin-bottom: 10px;
  font-size: 22px;
}

.grid-card p,
.list-item p,
.section-card p,
.download-copy,
.download-note,
.footer,
.page-nav small {
  color: var(--muted);
  line-height: 1.8;
}

.kicker,
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  color: #bdeeff;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.kicker::before,
.section-kicker::before {
  content: '';
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 0 rgba(103, 232, 165, 0.5);
  animation: pulse 1.8s infinite;
}

.page-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 18px;
}

.feature-visual {
  min-height: 430px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background:
    linear-gradient(180deg, rgba(3, 16, 31, 0.06), rgba(3, 16, 31, 0.46)),
    var(--feature-bg, url('/assets/chat-snow-lake-qtp.jpg')) center 48% / cover no-repeat;
  box-shadow: var(--shadow);
  overflow: hidden;
  position: relative;
}

.route-line {
  position: absolute;
  inset: 14% auto auto 9%;
  width: 62%;
  height: 58%;
  border: 2px dashed rgba(127, 233, 255, 0.35);
  border-right: 0;
  border-bottom: 0;
  border-radius: 280px 0 0 0;
  transform: rotate(10deg);
}

.feature-list {
  display: grid;
  gap: 14px;
}

.list-item {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 14px;
  padding: 20px;
  border-radius: 22px;
}

.icon {
  display: grid;
  place-items: center;
  width: 54px;
  height: 54px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.08);
  font-size: 24px;
}

.num {
  display: inline-grid;
  place-items: center;
  min-width: 42px;
  height: 42px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(127, 233, 255, 0.12);
  color: #dff9ff;
  font-weight: 800;
  margin-bottom: 18px;
}

.quick-links {
  margin-top: 42px;
}

.page-nav {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 36px;
}

.page-nav a {
  display: block;
  padding: 18px 20px;
  border-radius: 20px;
  text-decoration: none;
}

.page-nav strong {
  display: block;
  margin-top: 6px;
  font-size: 18px;
}

.download-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 20px;
  align-items: stretch;
}

.qr-card {
  display: grid;
  gap: 16px;
  padding: 22px;
  border-radius: 26px;
}

.qr-frame {
  display: grid;
  place-items: center;
  min-height: 250px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.qr-frame img {
  width: 100%;
  max-width: 220px;
  aspect-ratio: 1;
  object-fit: contain;
}

.qr-fallback {
  display: none;
  width: 100%;
  height: 100%;
  min-height: 220px;
  place-items: center;
  text-align: center;
  color: var(--muted);
  line-height: 1.8;
}

.wechat-tip {
  position: fixed;
  left: 50%;
  bottom: 18px;
  z-index: 30;
  transform: translate(-50%, 24px);
  max-width: min(92vw, 720px);
  padding: 14px 18px;
  border-radius: 16px;
  border: 1px solid rgba(255, 159, 63, 0.28);
  background: rgba(10, 24, 42, 0.92);
  color: #fff4e7;
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.22);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.24s ease, transform 0.24s ease;
}

.wechat-tip.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

.footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  margin-top: 34px;
  padding: 20px 4px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 13px;
}

.content-auto {
  content-visibility: auto;
  contain-intrinsic-size: 720px;
}

@keyframes rotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(103, 232, 165, 0.55); }
  70% { box-shadow: 0 0 0 10px rgba(103, 232, 165, 0); }
  100% { box-shadow: 0 0 0 0 rgba(103, 232, 165, 0); }
}

@keyframes floatGlow {
  from { transform: translate3d(0, 0, 0) scale(1); opacity: 0.78; }
  to { transform: translate3d(0, 26px, 0) scale(1.08); opacity: 1; }
}

@media (max-width: 1080px) {
  .hero,
  .page-split,
  .download-layout {
    grid-template-columns: 1fr;
  }

  .nav {
    padding-inline: 16px;
  }

  .nav-links {
    display: none;
  }
}

@media (max-width: 780px) {
  main {
    padding: 18px 14px 56px;
  }

  .hero {
    gap: 20px;
    padding-top: 18px;
    min-height: auto;
  }

  h1 {
    font-size: clamp(38px, 15vw, 64px);
    line-height: 1.02;
  }

  .hero-card,
  .visual-card {
    min-height: 500px;
  }

  .metric-grid,
  .grid.cols-2,
  .grid.cols-3,
  .page-nav {
    grid-template-columns: 1fr;
  }

  .button,
  .nav-cta {
    width: 100%;
  }

  .nav {
    gap: 12px;
  }
}

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