/* 丘腾官网 — 晨雾朱砂：冷雾青灰底 + 朱砂强调，非紫白/奶油报纸风 */
:root {
  --ink: #1a1614;
  --ink-soft: #3d3530;
  --muted: #6b635c;
  --fog: #dfe8ec;
  --fog-warm: #f3ece4;
  --paper: #faf8f5;
  --cinnabar: #c23a2b;
  --cinnabar-deep: #9e2e22;
  --line: rgba(26, 22, 20, 0.12);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --font-display: "ZCOOL XiaoWei", "Noto Serif SC", "Songti SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.55;
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}

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

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

/* 氛围底：流动雾带 + 细网格 */
.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  background:
    radial-gradient(ellipse 90% 70% at 12% 18%, rgba(223, 232, 236, 0.95), transparent 55%),
    radial-gradient(ellipse 80% 60% at 88% 12%, rgba(194, 58, 43, 0.12), transparent 50%),
    radial-gradient(ellipse 70% 50% at 70% 88%, rgba(243, 236, 228, 0.9), transparent 55%),
    linear-gradient(165deg, #e4eef2 0%, #f7f2ec 48%, #ebe4db 100%);
}

.atmosphere::before {
  content: "";
  position: absolute;
  inset: -20%;
  background-image:
    linear-gradient(rgba(26, 22, 20, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(26, 22, 20, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  transform: rotate(-6deg);
  animation: grid-drift 28s linear infinite;
  opacity: 0.55;
  pointer-events: none;
}

.atmosphere::after {
  content: "";
  position: absolute;
  width: 55vmax;
  height: 55vmax;
  left: -12%;
  bottom: -18%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(194, 58, 43, 0.08), transparent 68%);
  animation: blob-float 16s var(--ease) infinite alternate;
  pointer-events: none;
}

@keyframes grid-drift {
  from { transform: rotate(-6deg) translate3d(0, 0, 0); }
  to { transform: rotate(-6deg) translate3d(24px, 18px, 0); }
}

@keyframes blob-float {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to { transform: translate3d(6%, -4%, 0) scale(1.08); }
}

.site-header {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem clamp(1.25rem, 4vw, 3rem);
}

.nav-brand {
  font-family: var(--font-display);
  font-size: 1.35rem;
  letter-spacing: 0.08em;
  color: var(--ink);
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  font-size: 0.92rem;
  color: var(--ink-soft);
}

.nav-links a {
  position: relative;
  transition: color 0.25s var(--ease);
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.2em;
  width: 0;
  height: 1.5px;
  background: var(--cinnabar);
  transition: width 0.35s var(--ease);
}

.nav-links a:hover {
  color: var(--cinnabar);
}

.nav-links a:hover::after,
.nav-links a[aria-current="page"]::after {
  width: 100%;
}

/* —— Hero —— */
.hero {
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: clamp(1.5rem, 4vw, 3.5rem);
  padding: clamp(5.5rem, 12vh, 7rem) clamp(1.25rem, 5vw, 4rem) 3rem;
  max-width: 1180px;
  margin: 0 auto;
}

.hero-copy {
  max-width: 32rem;
}

.brand-mark {
  font-family: var(--font-display);
  font-size: clamp(3.6rem, 9vw, 6.4rem);
  line-height: 0.95;
  letter-spacing: 0.06em;
  margin: 0 0 1.1rem;
  color: var(--ink);
  opacity: 0;
  transform: translateY(28px);
  animation: rise 0.9s var(--ease) 0.08s forwards;
}

.brand-mark span {
  display: inline-block;
  color: var(--cinnabar);
}

.hero-title {
  margin: 0 0 0.85rem;
  font-size: clamp(1.15rem, 2.4vw, 1.55rem);
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--ink-soft);
  opacity: 0;
  transform: translateY(22px);
  animation: rise 0.9s var(--ease) 0.22s forwards;
}

.hero-lead {
  margin: 0 0 1.75rem;
  font-size: 1.02rem;
  color: var(--muted);
  max-width: 26rem;
  opacity: 0;
  transform: translateY(18px);
  animation: rise 0.9s var(--ease) 0.34s forwards;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem 1rem;
  align-items: center;
  opacity: 0;
  transform: translateY(16px);
  animation: rise 0.9s var(--ease) 0.46s forwards;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.85rem;
  padding: 0.65rem 1.45rem;
  border: 1.5px solid transparent;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: transform 0.3s var(--ease), background 0.3s var(--ease), border-color 0.3s var(--ease), color 0.3s var(--ease), opacity 0.3s;
}

.btn:focus-visible {
  outline: 2px solid var(--cinnabar);
  outline-offset: 3px;
}

.btn-primary {
  background: var(--cinnabar);
  color: #fffaf7;
  border-color: var(--cinnabar);
}

.btn-primary:hover:not([aria-disabled="true"]) {
  background: var(--cinnabar-deep);
  border-color: var(--cinnabar-deep);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--ink-soft);
  border-color: var(--line);
}

.btn-ghost:hover {
  border-color: var(--ink-soft);
  transform: translateY(-2px);
}

.btn[aria-disabled="true"],
.btn.is-disabled {
  opacity: 0.45;
  cursor: not-allowed;
  pointer-events: none;
  transform: none;
}

.hero-visual {
  position: relative;
  justify-self: end;
  width: min(100%, 420px);
  opacity: 0;
  transform: translateY(36px) scale(0.98);
  animation: rise-scale 1.05s var(--ease) 0.28s forwards;
}

.device-frame {
  position: relative;
  aspect-ratio: 9 / 17.5;
  border: 1.5px solid rgba(26, 22, 20, 0.18);
  background:
    linear-gradient(160deg, rgba(255, 255, 255, 0.55), rgba(255, 255, 255, 0.12)),
    linear-gradient(180deg, #2a2420 0%, #14110f 100%);
  padding: 0.7rem;
  box-shadow: none;
}

.device-screen {
  height: 100%;
  background:
    radial-gradient(circle at 50% 18%, rgba(194, 58, 43, 0.35), transparent 42%),
    linear-gradient(180deg, #3a322c 0%, #1c1917 55%, #12100e 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 1.5rem;
  color: #f5efe8;
}

.device-logo {
  width: 72px;
  height: 72px;
  object-fit: contain;
  border-radius: 14px;
}

.device-brand {
  font-family: var(--font-display);
  font-size: 1.85rem;
  letter-spacing: 0.12em;
}

.device-sub {
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  opacity: 0.65;
  text-transform: uppercase;
}

.visual-ribbon {
  position: absolute;
  inset: auto -8% -6% 18%;
  height: 42%;
  background: linear-gradient(105deg, transparent, rgba(194, 58, 43, 0.18), transparent);
  transform: skewY(-8deg);
  pointer-events: none;
  animation: ribbon-pulse 5.5s ease-in-out infinite;
}

@keyframes ribbon-pulse {
  0%, 100% { opacity: 0.55; }
  50% { opacity: 1; }
}

@keyframes rise {
  to { opacity: 1; transform: translateY(0); }
}

@keyframes rise-scale {
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* —— Download page —— */
.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.page-main {
  flex: 1;
  width: min(960px, 100%);
  margin: 0 auto;
  padding: clamp(5.5rem, 12vh, 7rem) clamp(1.25rem, 4vw, 2.5rem) 3rem;
}

.page-kicker {
  font-size: 0.85rem;
  letter-spacing: 0.16em;
  color: var(--muted);
  text-transform: uppercase;
  margin: 0 0 0.75rem;
}

.page-title {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  margin: 0 0 0.6rem;
  letter-spacing: 0.04em;
}

.page-lead {
  margin: 0 0 2.25rem;
  color: var(--muted);
  max-width: 34rem;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.download-item {
  padding: 1.35rem 0 1.5rem;
  border-top: 1.5px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  min-height: 11.5rem;
  opacity: 0;
  transform: translateY(20px);
  animation: rise 0.75s var(--ease) forwards;
}

.download-item:nth-child(1) { animation-delay: 0.12s; }
.download-item:nth-child(2) { animation-delay: 0.24s; }
.download-item:nth-child(3) { animation-delay: 0.36s; }

.download-item h2 {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 600;
}

.download-item p {
  margin: 0;
  flex: 1;
  font-size: 0.92rem;
  color: var(--muted);
}

.download-meta {
  font-size: 0.8rem;
  color: var(--muted);
  min-height: 1.2em;
}

.qr-slot {
  width: 96px;
  height: 96px;
  border: 1px dashed var(--line);
  display: grid;
  place-items: center;
  font-size: 0.72rem;
  color: var(--muted);
  margin-top: 0.35rem;
}

.qr-slot img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.req-note {
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
  color: var(--muted);
}

.status-banner {
  margin-bottom: 1.25rem;
  font-size: 0.88rem;
  color: var(--muted);
}

/* —— Footer —— */
.site-footer {
  margin-top: auto;
  padding: 1.5rem clamp(1.25rem, 4vw, 3rem) 1.75rem;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  justify-content: space-between;
  align-items: center;
  font-size: 0.82rem;
  color: var(--muted);
  background: rgba(250, 248, 245, 0.55);
  backdrop-filter: blur(6px);
}

.site-footer a {
  color: var(--muted);
  border-bottom: 1px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}

.site-footer a:hover {
  color: var(--ink-soft);
  border-bottom-color: var(--ink-soft);
}

.beian-link.is-placeholder {
  opacity: 0.75;
  font-style: italic;
}

.footer-legal a {
  color: var(--muted);
}

.legal-main .policy-container {
  max-width: 800px;
}

.legal-main .policy-header h1 {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2rem);
  font-weight: 700;
  color: var(--ink);
  border-bottom: 2px solid var(--cinnabar);
  padding-bottom: 12px;
  margin: 0 0 16px;
}

.legal-main .policy-subtitle {
  color: var(--muted);
  margin-bottom: 8px;
}

.legal-main .policy-version {
  color: var(--muted);
  font-size: 0.875rem;
  margin-bottom: 24px;
}

.legal-main .policy-h2,
.legal-main .policy-h3,
.legal-main .policy-h4 {
  color: var(--cinnabar-deep);
  margin: 24px 0 12px;
  font-size: 1.1rem;
}

.legal-main .policy-section p,
.legal-main .policy-section li {
  color: var(--ink-soft);
  margin-bottom: 12px;
}

.legal-main .policy-sdk-block {
  border: 1px solid rgba(194, 58, 43, 0.25);
  border-radius: 8px;
  padding: 12px 14px;
  margin: 12px 0;
  background: rgba(194, 58, 43, 0.06);
  white-space: pre-line;
}

.legal-main .policy-footer {
  border-top: 1px solid var(--line);
  padding-top: 24px;
  margin-top: 32px;
  color: var(--muted);
  font-size: 0.875rem;
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-bottom: 2.5rem;
  }

  .hero-visual {
    justify-self: center;
    width: min(100%, 280px);
    order: -1;
  }

  .device-frame {
    aspect-ratio: 9 / 14;
  }

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

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  .brand-mark,
  .hero-title,
  .hero-lead,
  .cta-row,
  .hero-visual,
  .download-item {
    opacity: 1;
    transform: none;
  }
}