:root {
  --bg: #060a16;
  --bg-soft: #0b1226;
  --panel: rgba(255, 255, 255, 0.035);
  --panel-strong: rgba(255, 255, 255, 0.06);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --text: #e9efff;
  --muted: #8e9ac0;
  --accent: #4e6bff;
  --accent-soft: rgba(78, 107, 255, 0.16);
  --cyan: #5fe8ff;
  --pink: #ff9ec4;
  --radius: 18px;
  --font: "PingFang SC", "Microsoft YaHei", "HarmonyOS Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

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

/* ---------- 背景装饰 ---------- */
.bg-fx { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(110px);
  opacity: 0.5;
}
.orb-a {
  width: 640px; height: 640px;
  left: -220px; top: -180px;
  background: radial-gradient(circle, rgba(78, 107, 255, 0.55), transparent 65%);
  animation: drift 22s ease-in-out infinite alternate;
}
.orb-b {
  width: 560px; height: 560px;
  right: -200px; top: 30%;
  background: radial-gradient(circle, rgba(95, 232, 255, 0.3), transparent 65%);
  animation: drift 26s ease-in-out infinite alternate-reverse;
}
@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(70px, 50px) scale(1.12); }
}
.grid-overlay {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 40%, transparent 100%);
}

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; gap: 32px;
  max-width: 1200px; margin: 0 auto;
  padding: 16px 24px;
  backdrop-filter: blur(16px);
  background: rgba(6, 10, 22, 0.72);
  border-bottom: 1px solid var(--border);
}
.nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: 17px; letter-spacing: 0.5px;
}
.nav-links { display: flex; gap: 26px; margin-left: auto; }
.nav-links a {
  color: var(--muted); font-size: 14.5px;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  border-radius: 12px; font-weight: 600; cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.18s, box-shadow 0.18s, background 0.18s, border-color 0.18s;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px) scale(0.99); }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-big { padding: 14px 26px; font-size: 15.5px; }
.btn-block { width: 100%; padding: 13px 20px; font-size: 15px; }
.btn-primary {
  background: linear-gradient(135deg, #4e6bff, #6a5cff);
  color: #fff;
  box-shadow: 0 6px 24px rgba(78, 107, 255, 0.35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 32px rgba(78, 107, 255, 0.5);
}
.btn-ghost {
  background: var(--panel);
  border-color: var(--border-strong);
  color: var(--text);
}
.btn-ghost:hover {
  background: var(--panel-strong);
  border-color: rgba(95, 232, 255, 0.4);
  transform: translateY(-2px);
}
.btn-ghost.demo-on {
  background: rgba(95, 232, 255, 0.12);
  border-color: rgba(95, 232, 255, 0.5);
  color: var(--cyan);
}

/* ---------- Hero ---------- */
.hero {
  display: grid;
  grid-template-columns: 1.02fr 0.98fr;
  align-items: center;
  gap: 40px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 72px 24px 64px;
  min-height: calc(100vh - 70px);
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 7px 16px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--border-strong);
  color: var(--muted); font-size: 13.5px;
  margin-bottom: 26px;
}
.hero-badge .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: #6ee7a0;
  box-shadow: 0 0 10px #6ee7a0;
  animation: pulse 2.2s infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.4; } }
.hero h1 {
  font-size: clamp(42px, 5.5vw, 66px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: 1px;
  margin-bottom: 14px;
}
.grad-text {
  background: linear-gradient(120deg, #5fe8ff, #4e6bff 55%, #a78bff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.tagline {
  font-size: clamp(18px, 2.2vw, 24px);
  color: var(--cyan);
  font-weight: 600;
  margin-bottom: 18px;
}
.desc {
  color: var(--muted);
  font-size: 16px;
  max-width: 520px;
  margin-bottom: 32px;
}
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 36px; }
.hero-stats { display: flex; gap: 40px; margin-bottom: 22px; }
.stat b {
  display: block;
  font-size: 26px; font-weight: 800;
  background: linear-gradient(120deg, #e9efff, #8fb0ff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.stat span { color: var(--muted); font-size: 13px; }
.hero-hint { color: var(--muted); font-size: 13.5px; opacity: 0.85; }

/* 3D 舞台 */
.hero-stage { display: flex; flex-direction: column; gap: 14px; }
.stage-card {
  position: relative;
  height: clamp(360px, 46vw, 480px);
  border-radius: 24px;
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, rgba(78, 107, 255, 0.14), transparent 70%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.045), rgba(255, 255, 255, 0.015));
  border: 1px solid var(--border-strong);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.08),
    0 24px 80px rgba(0, 0, 0, 0.45);
  overflow: hidden;
  cursor: default;
}
.stage-card.hover { cursor: pointer; }
.stage-card canvas { position: absolute; inset: 0; display: block; }

.bubble {
  position: absolute;
  top: 16px; left: 50%;
  transform: translateX(-50%) translateY(-6px) scale(0.95);
  padding: 8px 18px;
  background: rgba(13, 20, 40, 0.92);
  border: 1px solid rgba(95, 232, 255, 0.35);
  border-radius: 999px;
  color: #dceaff; font-size: 14px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4), 0 0 20px rgba(95, 232, 255, 0.12);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s, transform 0.25s;
  z-index: 5;
}
.bubble.show { opacity: 1; transform: translateX(-50%) translateY(0) scale(1); }

/* ---------- 区块 ---------- */
.section {
  max-width: 1200px;
  margin: 0 auto;
  padding: 88px 24px;
}
.section-head { text-align: center; margin-bottom: 52px; }
.section-tag {
  display: inline-block;
  padding: 5px 15px;
  border-radius: 999px;
  background: var(--accent-soft);
  border: 1px solid rgba(78, 107, 255, 0.35);
  color: #9db4ff; font-size: 13px; font-weight: 600;
  margin-bottom: 16px;
}
.section-head h2 {
  font-size: clamp(26px, 3.4vw, 38px);
  font-weight: 800;
  margin-bottom: 10px;
}
.section-head p { color: var(--muted); font-size: 15.5px; }

/* 功能卡片 */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.card {
  padding: 28px 26px;
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--border);
  transition: transform 0.22s, border-color 0.22s, background 0.22s, box-shadow 0.22s;
}
.card:hover {
  transform: translateY(-5px);
  background: var(--panel-strong);
  border-color: var(--border-strong);
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.35);
}
.card h3 { font-size: 18px; margin: 18px 0 8px; }
.card p { color: var(--muted); font-size: 14.5px; }
.card-icon {
  width: 46px; height: 46px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 13px;
}
.card-icon svg { width: 24px; height: 24px; }
.ci-blue { background: rgba(78, 107, 255, 0.16); color: #8fa4ff; box-shadow: inset 0 0 0 1px rgba(78, 107, 255, 0.3); }
.ci-cyan { background: rgba(95, 232, 255, 0.12); color: #7feaf9; box-shadow: inset 0 0 0 1px rgba(95, 232, 255, 0.28); }
.ci-violet { background: rgba(167, 139, 255, 0.14); color: #b7a4ff; box-shadow: inset 0 0 0 1px rgba(167, 139, 255, 0.3); }
.ci-pink { background: rgba(255, 158, 196, 0.13); color: #ffa8c9; box-shadow: inset 0 0 0 1px rgba(255, 158, 196, 0.28); }
.ci-red { background: rgba(255, 122, 122, 0.13); color: #ff9a9a; box-shadow: inset 0 0 0 1px rgba(255, 122, 122, 0.28); }
.ci-green { background: rgba(110, 231, 160, 0.12); color: #8feab4; box-shadow: inset 0 0 0 1px rgba(110, 231, 160, 0.26); }

/* 服务商 */
.providers {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.provider {
  padding: 22px 22px 20px;
  border-radius: 15px;
  background: var(--panel);
  border: 1px solid var(--border);
  transition: transform 0.2s, border-color 0.2s, background 0.2s;
}
.provider:hover {
  transform: translateY(-4px);
  background: var(--panel-strong);
  border-color: rgba(95, 232, 255, 0.3);
}
.p-name { font-weight: 700; font-size: 16.5px; margin-bottom: 5px; }
.p-models { color: var(--muted); font-size: 13px; }
.provider-custom {
  background: linear-gradient(135deg, rgba(78, 107, 255, 0.12), rgba(95, 232, 255, 0.07));
  border-color: rgba(78, 107, 255, 0.35);
}
.provider-custom .p-name { color: #9db4ff; }

/* 步骤 */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.step {
  position: relative;
  padding: 30px 26px;
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--border);
}
.step-num {
  width: 42px; height: 42px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 50%;
  font-weight: 800; font-size: 18px;
  background: linear-gradient(135deg, #4e6bff, #5fe8ff);
  color: #061020;
  margin-bottom: 18px;
  box-shadow: 0 6px 20px rgba(78, 107, 255, 0.35);
}
.step h3 { font-size: 18px; margin-bottom: 8px; }
.step p { color: var(--muted); font-size: 14.5px; }

/* 下载 */
.dl-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  max-width: 860px;
  margin: 0 auto;
}
.dl-card {
  position: relative;
  padding: 30px 28px;
  border-radius: 20px;
  background: var(--panel);
  border: 1px solid var(--border);
  display: flex; flex-direction: column; gap: 14px;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}
.dl-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 56px rgba(0, 0, 0, 0.4);
}
.dl-primary {
  background:
    radial-gradient(ellipse 90% 70% at 50% 0%, rgba(78, 107, 255, 0.16), transparent 70%),
    var(--panel);
  border-color: rgba(78, 107, 255, 0.4);
}
.dl-primary:hover { border-color: rgba(78, 107, 255, 0.65); }
.dl-badge {
  position: absolute;
  top: -12px; right: 22px;
  padding: 4px 14px;
  border-radius: 999px;
  background: linear-gradient(135deg, #4e6bff, #5fe8ff);
  color: #061020;
  font-size: 12.5px; font-weight: 800;
  box-shadow: 0 6px 18px rgba(78, 107, 255, 0.4);
}
.dl-title { display: flex; align-items: center; gap: 16px; color: #9db4ff; }
.dl-title h3 { font-size: 21px; }
.dl-meta { color: var(--muted); font-size: 13.5px; }
.dl-desc { color: var(--muted); font-size: 14.5px; flex: 1; }

/* FAQ */
.faq-list { max-width: 780px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-list details {
  border-radius: 14px;
  background: var(--panel);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: border-color 0.2s;
}
.faq-list details[open] { border-color: rgba(78, 107, 255, 0.4); }
.faq-list summary {
  list-style: none;
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 22px;
  font-weight: 600; font-size: 15.5px;
  cursor: pointer;
  user-select: none;
}
.faq-list summary::-webkit-details-marker { display: none; }
.chev { color: var(--muted); transition: transform 0.25s; flex-shrink: 0; }
details[open] .chev { transform: rotate(180deg); color: var(--cyan); }
.faq-list p { padding: 0 22px 20px; color: var(--muted); font-size: 14.5px; }

/* ---------- 页脚 ---------- */
.footer {
  border-top: 1px solid var(--border);
  background: rgba(6, 10, 22, 0.6);
  padding: 40px 24px 46px;
}
.footer-inner {
  max-width: 1200px; margin: 0 auto;
  display: flex; flex-direction: column; align-items: center; gap: 10px;
  text-align: center;
}
.footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.footer-line { color: var(--muted); font-size: 14px; }
.footer-copy { color: var(--muted); font-size: 13px; opacity: 0.7; }

/* ---------- 入场动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .nav-links { display: none; }
  .hero {
    grid-template-columns: 1fr;
    padding-top: 48px;
    min-height: auto;
  }
  .hero-copy { text-align: center; }
  .desc { margin-left: auto; margin-right: auto; }
  .hero-cta, .hero-stats { justify-content: center; }
  .cards { grid-template-columns: 1fr 1fr; }
  .providers { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: 1fr; }
  .dl-grid { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .cards { grid-template-columns: 1fr; }
  .providers { grid-template-columns: 1fr; }
  .hero-stats { gap: 26px; }
}

/* 弱动画偏好 */
@media (prefers-reduced-motion: reduce) {
  .reveal { transition: none; opacity: 1; transform: none; }
  .orb { animation: none; }
}