:root {
  --bg: #0b1020;
  --ink: #f2f5ff;
  --muted: #9aa8c7;
  --line: rgba(140, 170, 255, 0.22);
  --cyan: #34d6ff;
  --orange: #ff7a3d;
  --violet: #6d8cff;
  --ok: #45d69a;
  --panel: rgba(18, 26, 48, 0.88);
  --shadow: 0 30px 60px rgba(0, 0, 0, 0.45);
  --radius: 18px;
  --font-display: "Impact", "Arial Black", "Segoe UI Variable", "PingFang SC", "Microsoft YaHei UI", sans-serif;
  --font-body: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: var(--font-body);
  background:
    radial-gradient(circle at 50% 0%, rgba(52, 214, 255, 0.16), transparent 34%),
    radial-gradient(circle at 90% 20%, rgba(255, 122, 61, 0.14), transparent 28%),
    linear-gradient(180deg, #10182e 0%, var(--bg) 45%, #070b16 100%);
  line-height: 1.65;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font: inherit; cursor: pointer; }

.container {
  width: min(1140px, calc(100% - 2rem));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 16, 32, 0.86);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}

.nav {
  min-height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-family: var(--font-display);
  letter-spacing: 0.04em;
}

.logo-mark {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: #081018;
  background: linear-gradient(145deg, var(--cyan), var(--orange));
  box-shadow: 0 10px 24px rgba(52, 214, 255, 0.35);
  transform: perspective(400px) rotateY(-18deg) rotateX(8deg);
  font-size: 0.78rem;
}

.logo-text span { color: var(--cyan); }

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.05rem;
  color: var(--muted);
}

.nav-links a:hover,
.nav-links a.active { color: var(--cyan); }

.lang-switch {
  display: flex;
  gap: 0.25rem;
  padding: 0.22rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
}

.lang-switch button {
  border: 0;
  background: transparent;
  color: var(--muted);
  border-radius: 999px;
  padding: 0.32rem 0.72rem;
}

.lang-switch button.active {
  background: rgba(52, 214, 255, 0.16);
  color: var(--ink);
}

.hero {
  position: relative;
  padding: 4.2rem 0 3rem;
  perspective: 1200px;
}

.hero::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 18%;
  width: 140%;
  height: 520px;
  transform: translateX(-50%) perspective(900px) rotateX(62deg);
  background:
    linear-gradient(90deg, transparent, rgba(52, 214, 255, 0.08), transparent),
    repeating-linear-gradient(90deg, rgba(109, 140, 255, 0.16) 0 1px, transparent 1px 56px),
    repeating-linear-gradient(0deg, rgba(255, 122, 61, 0.12) 0 1px, transparent 1px 56px);
  mask-image: linear-gradient(180deg, #000 20%, transparent 85%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 2rem;
  align-items: center;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.tag {
  display: inline-flex;
  padding: 0.3rem 0.72rem;
  border-radius: 999px;
  border: 1px solid rgba(52, 214, 255, 0.28);
  background: rgba(18, 26, 48, 0.75);
  color: var(--muted);
  font-size: 0.84rem;
}

.hero h1 {
  margin: 0 0 0.9rem;
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 4.6vw, 3.5rem);
  line-height: 1.1;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  max-width: 12ch;
  transform: perspective(700px) rotateY(-4deg);
}

.hero h1 em {
  font-style: normal;
  color: transparent;
  background: linear-gradient(90deg, var(--cyan), var(--orange));
  -webkit-background-clip: text;
  background-clip: text;
}

.hero-lead {
  margin: 0 0 1.4rem;
  color: var(--muted);
  max-width: 40rem;
  font-size: 1.04rem;
}

.hero-actions,
.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-bottom: 1.35rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.72rem 1.3rem;
  border-radius: 14px;
  border: 1px solid transparent;
  font-family: var(--font-display);
  letter-spacing: 0.03em;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover { transform: translateY(-3px) scale(1.02); }

.btn-primary {
  background: linear-gradient(135deg, var(--cyan), #1ea8d8 45%, var(--orange));
  color: #081018;
  box-shadow: 0 14px 30px rgba(52, 214, 255, 0.28);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.03);
  border-color: var(--line);
  color: var(--ink);
}

.trust-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
}

.trust-item {
  padding: 0.9rem 1rem;
  border-radius: 16px;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(52, 214, 255, 0.08), transparent);
  transform: perspective(600px) rotateX(8deg);
}

.trust-item strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.trust-item span {
  color: var(--muted);
  font-size: 0.85rem;
}

.poster-stage {
  position: relative;
  min-height: 430px;
  perspective: 1000px;
}

.poster-card {
  position: absolute;
  inset: 8% 8% 8% 12%;
  border-radius: 24px;
  padding: 1rem;
  border: 1px solid rgba(52, 214, 255, 0.35);
  background:
    linear-gradient(160deg, rgba(52, 214, 255, 0.14), transparent 40%),
    linear-gradient(320deg, rgba(255, 122, 61, 0.16), transparent 42%),
    rgba(12, 18, 34, 0.95);
  box-shadow: var(--shadow), 0 0 0 1px rgba(255, 255, 255, 0.04);
  transform: rotateY(-22deg) rotateX(10deg) translateZ(20px);
  animation: floatPoster 7s ease-in-out infinite;
}

.poster-card img {
  border-radius: 16px;
  aspect-ratio: 4/3;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.poster-badge {
  position: absolute;
  top: -0.7rem;
  right: -0.5rem;
  padding: 0.45rem 0.8rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--orange), #ff9a4d);
  color: #1a0c05;
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  box-shadow: 0 12px 24px rgba(255, 122, 61, 0.35);
  transform: rotate(8deg);
}

.poster-ghost {
  position: absolute;
  inset: 18% 4% 4% 22%;
  border-radius: 24px;
  border: 1px dashed rgba(109, 140, 255, 0.35);
  background: rgba(109, 140, 255, 0.08);
  transform: rotateY(-28deg) rotateX(14deg) translateZ(-40px);
}

.section { padding: 3.5rem 0; }

.section-head {
  margin-bottom: 1.5rem;
  max-width: 46rem;
}

.section-kicker {
  display: inline-flex;
  margin-bottom: 0.5rem;
  color: var(--orange);
  font-family: var(--font-display);
  letter-spacing: 0.12em;
  font-size: 0.86rem;
}

.section-head h2 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.3rem);
  line-height: 1.2;
  letter-spacing: 0.02em;
}

.section-head p {
  margin: 0;
  color: var(--muted);
}

.platform-grid,
.feature-grid,
.recommend-grid,
.scene-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  perspective: 1200px;
}

.compat-grid,
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.platform-card,
.feature-card,
.recommend-card,
.scene-card,
.faq-item,
.step-card,
.compat-item,
.hint-box,
.docs-panel,
.download-card,
.flow-panel,
.preview-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.platform-card,
.feature-card,
.recommend-card,
.scene-card,
.faq-item,
.step-card,
.compat-item,
.hint-box,
.docs-panel,
.flow-panel,
.preview-panel {
  padding: 1.2rem 1.25rem;
}

.platform-card,
.feature-card,
.recommend-card {
  transform: perspective(900px) rotateY(-6deg) rotateX(4deg);
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.platform-card:hover,
.feature-card:hover,
.recommend-card:hover {
  transform: perspective(900px) rotateY(0deg) rotateX(0deg) translateY(-6px);
  border-color: rgba(52, 214, 255, 0.45);
}

.platform-card h3,
.feature-card h3,
.recommend-card h3,
.scene-card h3,
.faq-item h3,
.step-card h3,
.docs-panel h3 {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.platform-card p,
.feature-card p,
.recommend-card p,
.scene-card p,
.faq-item p,
.step-card p,
.compat-item p,
.hint-box p,
.docs-panel p,
.download-card p {
  margin: 0;
  color: var(--muted);
}

.meta-list {
  list-style: none;
  margin: 0.8rem 0 1rem;
  padding: 0;
  display: grid;
  gap: 0.4rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.meta-list li {
  display: flex;
  gap: 0.45rem;
}

.meta-list li::before {
  content: "▶";
  color: var(--cyan);
  font-size: 0.65rem;
  margin-top: 0.35rem;
}

.os-badge {
  display: inline-flex;
  margin-bottom: 0.7rem;
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  background: rgba(255, 122, 61, 0.14);
  border: 1px solid rgba(255, 122, 61, 0.35);
  color: var(--orange);
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
}

.feature-index {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  margin-bottom: 0.75rem;
  background: linear-gradient(145deg, rgba(52, 214, 255, 0.2), rgba(255, 122, 61, 0.18));
  border: 1px solid rgba(52, 214, 255, 0.35);
  color: var(--cyan);
  font-family: var(--font-display);
}

.how-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  perspective: 1000px;
}

.flow-panel { transform: perspective(900px) rotateY(6deg); }
.preview-panel { transform: perspective(900px) rotateY(-6deg); }

.flow-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.flow-list li {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 0.8rem;
}

.flow-num {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: linear-gradient(145deg, var(--cyan), var(--violet));
  color: #081018;
  font-family: var(--font-display);
}

.flow-list h3 {
  margin: 0 0 0.25rem;
  font-size: 1.02rem;
  font-family: var(--font-display);
}

.flow-list p {
  margin: 0;
  color: var(--muted);
}

.preview-panel img {
  border-radius: 14px;
  border: 1px solid var(--line);
  margin-bottom: 0.85rem;
}

.code-box {
  margin: 0;
  padding: 0.95rem 1rem;
  border-radius: 12px;
  background: #070b16;
  border: 1px solid rgba(52, 214, 255, 0.18);
  color: #b8f0ff;
  font-size: 0.84rem;
  overflow-x: auto;
  line-height: 1.55;
}

.ability-row {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.75rem;
}

.ability-row span {
  display: block;
  padding: 0.85rem 0.95rem;
  border-radius: 14px;
  border: 1px dashed rgba(52, 214, 255, 0.28);
  background: rgba(255, 255, 255, 0.02);
  color: var(--muted);
  font-size: 0.9rem;
}

.compat-item {
  display: grid;
  grid-template-columns: 50px 1fr;
  gap: 0.85rem;
  align-items: start;
}

.compat-dot {
  width: 50px;
  height: 50px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: rgba(109, 140, 255, 0.12);
  border: 1px solid rgba(109, 140, 255, 0.35);
  color: var(--violet);
  font-family: var(--font-display);
  font-size: 0.74rem;
}

.recommend-card .badge {
  display: inline-flex;
  margin-bottom: 0.65rem;
  padding: 0.22rem 0.65rem;
  border-radius: 999px;
  background: rgba(69, 214, 154, 0.12);
  color: var(--ok);
  border: 1px solid rgba(69, 214, 154, 0.28);
  font-size: 0.8rem;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
  perspective: 1000px;
}

.step-card {
  transform: perspective(800px) rotateX(8deg);
}

.step-label {
  display: inline-block;
  margin-bottom: 0.55rem;
  color: var(--cyan);
  font-family: var(--font-display);
  letter-spacing: 0.08em;
  font-size: 0.86rem;
}

.hint-box {
  border-color: rgba(255, 122, 61, 0.35);
  background:
    radial-gradient(circle at 0% 0%, rgba(255, 122, 61, 0.14), transparent 45%),
    var(--panel);
}

.hint-box strong {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--orange);
  font-family: var(--font-display);
}

.scene-card { min-height: 150px; }

.cta-band {
  margin: 0.5rem 0 3rem;
  padding: 2.4rem;
  border-radius: 28px;
  text-align: center;
  border: 1px solid rgba(52, 214, 255, 0.3);
  background:
    radial-gradient(circle at 20% 0%, rgba(52, 214, 255, 0.2), transparent 40%),
    radial-gradient(circle at 80% 100%, rgba(255, 122, 61, 0.18), transparent 40%),
    linear-gradient(135deg, #121a32, #182244);
  box-shadow: var(--shadow);
  transform: perspective(1000px) rotateX(4deg);
}

.cta-band h2 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 3vw, 2.2rem);
  letter-spacing: 0.03em;
}

.cta-band p {
  margin: 0 auto 1.2rem;
  max-width: 34rem;
  color: var(--muted);
}

.cta-actions { justify-content: center; margin-bottom: 0; }

.site-footer {
  border-top: 1px solid var(--line);
  background: #070b16;
  padding: 2.8rem 0 1.3rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.35fr repeat(4, 1fr);
  gap: 1.1rem;
  margin-bottom: 1.5rem;
}

.site-footer h3,
.site-footer h4 {
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  letter-spacing: 0.03em;
}

.site-footer p,
.site-footer li,
.site-footer a { color: var(--muted); }

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
}

.site-footer a:hover { color: var(--cyan); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  padding-top: 1rem;
  border-top: 1px solid rgba(140, 170, 255, 0.12);
  color: #6f7f9e;
  font-size: 0.9rem;
}

.page-hero {
  padding: 3rem 0 1rem;
}

.page-hero h1 {
  margin: 0 0 0.7rem;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.4vw, 2.6rem);
  letter-spacing: 0.02em;
  transform: perspective(700px) rotateY(-3deg);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 46rem;
}

.download-list {
  display: grid;
  gap: 0.9rem;
  perspective: 1000px;
}

.download-card {
  display: grid;
  grid-template-columns: 1.25fr 1fr auto;
  gap: 1rem;
  align-items: center;
  padding: 1.2rem 1.3rem;
  transform: perspective(900px) rotateX(4deg);
  transition: transform 0.2s ease;
}

.download-card:hover {
  transform: perspective(900px) rotateX(0deg) translateY(-3px);
}

.download-card h3 {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
}

.status {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--ok);
  font-weight: 700;
  font-size: 0.88rem;
}

.status::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 10px var(--ok);
}

.inline-img {
  border-radius: 18px;
  border: 1px solid var(--line);
  margin: 1rem 0;
  box-shadow: var(--shadow);
  transform: perspective(900px) rotateY(-4deg);
}

.tutorial-layout { display: grid; gap: 1rem; }

@keyframes floatPoster {
  0%, 100% { transform: rotateY(-22deg) rotateX(10deg) translateZ(20px) translateY(0); }
  50% { transform: rotateY(-18deg) rotateX(8deg) translateZ(28px) translateY(-8px); }
}

@media (max-width: 980px) {
  .hero-grid,
  .how-grid,
  .download-card,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .poster-stage { min-height: 360px; }
  .poster-card,
  .poster-ghost,
  .platform-card,
  .feature-card,
  .recommend-card,
  .flow-panel,
  .preview-panel,
  .step-card,
  .cta-band,
  .download-card,
  .inline-img,
  .hero h1,
  .page-hero h1 {
    transform: none;
  }

  .platform-grid,
  .feature-grid,
  .recommend-grid,
  .scene-grid,
  .steps,
  .ability-row {
    grid-template-columns: 1fr 1fr;
  }

  .nav-links { display: none; }
}

@media (max-width: 640px) {
  .platform-grid,
  .feature-grid,
  .recommend-grid,
  .scene-grid,
  .steps,
  .ability-row,
  .compat-grid,
  .faq-grid,
  .trust-row {
    grid-template-columns: 1fr;
  }

  .cta-band { padding: 1.5rem; }
  .poster-stage { min-height: 300px; }
}