:root {
  --bg: #050714;
  --ink: #eef3ff;
  --muted: #9aa7c7;
  --line: rgba(160, 180, 255, 0.22);
  --neon: #6ef3ff;
  --magenta: #ff5ec8;
  --violet: #8b7cff;
  --ok: #5dffb0;
  --panel: rgba(16, 20, 48, 0.72);
  --shadow: 0 24px 50px rgba(0, 0, 0, 0.45);
  --radius: 20px;
  --font-display: "Segoe UI Variable", "Bahnschrift", "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 15% 10%, rgba(255, 94, 200, 0.18), transparent 26%),
    radial-gradient(circle at 85% 15%, rgba(110, 243, 255, 0.16), transparent 28%),
    radial-gradient(circle at 50% 80%, rgba(139, 124, 255, 0.14), transparent 34%),
    linear-gradient(180deg, #0a0e24 0%, var(--bg) 45%, #03040c 100%);
  line-height: 1.65;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image:
    radial-gradient(1px 1px at 20px 30px, rgba(255, 255, 255, 0.7), transparent),
    radial-gradient(1px 1px at 80px 120px, rgba(255, 255, 255, 0.45), transparent),
    radial-gradient(1.5px 1.5px at 160px 70px, rgba(110, 243, 255, 0.7), transparent),
    radial-gradient(1px 1px at 260px 180px, rgba(255, 94, 200, 0.55), transparent),
    radial-gradient(1px 1px at 340px 40px, rgba(255, 255, 255, 0.4), transparent);
  background-size: 380px 240px;
  opacity: 0.35;
  pointer-events: none;
  z-index: 0;
}

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;
  position: relative;
  z-index: 1;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(5, 7, 20, 0.78);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.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);
  font-weight: 700;
  letter-spacing: 0.03em;
}

.logo-mark {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #081018;
  background: conic-gradient(from 200deg, var(--neon), var(--violet), var(--magenta), var(--neon));
  box-shadow: 0 0 24px rgba(110, 243, 255, 0.35);
  font-size: 0.78rem;
}

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

.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(--neon); }

.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(110, 243, 255, 0.14);
  color: var(--ink);
}

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

.hero-grid {
  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(110, 243, 255, 0.28);
  background: rgba(16, 20, 48, 0.7);
  color: var(--muted);
  font-size: 0.84rem;
}

.hero h1 {
  margin: 0 0 0.9rem;
  font-family: var(--font-display);
  font-size: clamp(2.05rem, 4.4vw, 3.3rem);
  line-height: 1.14;
  max-width: 13ch;
}

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

.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: 999px;
  border: 1px solid transparent;
  font-family: var(--font-display);
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover { transform: translateY(-2px); }

.btn-primary {
  background: linear-gradient(135deg, var(--neon), #4bb8ff 45%, var(--magenta));
  color: #081018;
  box-shadow: 0 0 28px rgba(110, 243, 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: 18px;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(110, 243, 255, 0.08), transparent);
}

.trust-item strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.1rem;
}

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

.space-stage {
  position: relative;
  min-height: 430px;
  display: grid;
  place-items: center;
}

.planet {
  position: relative;
  width: min(100%, 380px);
  aspect-ratio: 1;
  border-radius: 50%;
  background:
    radial-gradient(circle at 30% 28%, rgba(255, 255, 255, 0.35), transparent 18%),
    radial-gradient(circle at 60% 70%, rgba(255, 94, 200, 0.35), transparent 40%),
    radial-gradient(circle at 40% 40%, rgba(110, 243, 255, 0.25), transparent 50%),
    linear-gradient(145deg, #1a2150, #0c1230 55%, #1d1540);
  border: 1px solid rgba(110, 243, 255, 0.28);
  box-shadow:
    0 0 60px rgba(139, 124, 255, 0.3),
    inset 0 0 50px rgba(110, 243, 255, 0.12);
  overflow: hidden;
  animation: planetPulse 8s ease-in-out infinite;
}

.planet img {
  position: absolute;
  inset: 16%;
  width: 68%;
  height: 68%;
  object-fit: cover;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.ring {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 120%;
  height: 36%;
  border: 2px solid rgba(110, 243, 255, 0.35);
  border-radius: 50%;
  transform: translate(-50%, -50%) rotateX(72deg);
  box-shadow: 0 0 20px rgba(110, 243, 255, 0.2);
  animation: ringSpin 12s linear infinite;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(0.2px);
  animation: orbFloat 5.5s ease-in-out infinite;
}

.orb-a {
  width: 18px;
  height: 18px;
  background: var(--neon);
  top: 8%;
  right: 18%;
  box-shadow: 0 0 18px var(--neon);
}

.orb-b {
  width: 12px;
  height: 12px;
  background: var(--magenta);
  bottom: 16%;
  left: 12%;
  box-shadow: 0 0 16px var(--magenta);
  animation-delay: 0.8s;
}

.orb-c {
  width: 10px;
  height: 10px;
  background: var(--violet);
  top: 42%;
  left: 4%;
  box-shadow: 0 0 14px var(--violet);
  animation-delay: 1.4s;
}

.section { padding: 3.5rem 0; }

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

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-bottom: 0.5rem;
  color: var(--magenta);
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: 0.1em;
  font-size: 0.86rem;
  text-transform: uppercase;
}

.section-kicker::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 12px var(--neon);
}

.section-head h2 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 2.9vw, 2.2rem);
  line-height: 1.25;
}

.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;
}

.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);
  backdrop-filter: blur(10px);
}

.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 {
  transition: transform 0.22s ease, border-color 0.22s ease, box-shadow 0.22s ease;
}

.platform-card:hover,
.feature-card:hover,
.recommend-card:hover {
  transform: translateY(-4px);
  border-color: rgba(110, 243, 255, 0.45);
  box-shadow: 0 0 28px rgba(110, 243, 255, 0.12), var(--shadow);
}

.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: 1.12rem;
}

.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(--neon);
}

.os-badge {
  display: inline-flex;
  margin-bottom: 0.7rem;
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  background: rgba(255, 94, 200, 0.12);
  border: 1px solid rgba(255, 94, 200, 0.3);
  color: var(--magenta);
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.05em;
}

.feature-index {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  margin-bottom: 0.75rem;
  background: rgba(110, 243, 255, 0.1);
  border: 1px solid rgba(110, 243, 255, 0.35);
  color: var(--neon);
  font-family: var(--font-display);
  font-weight: 700;
}

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

.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: 50%;
  display: grid;
  place-items: center;
  background: linear-gradient(145deg, rgba(110, 243, 255, 0.3), rgba(255, 94, 200, 0.25));
  border: 1px solid rgba(110, 243, 255, 0.4);
  font-family: var(--font-display);
  font-weight: 700;
}

.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: 16px;
  border: 1px solid var(--line);
  margin-bottom: 0.85rem;
}

.code-box {
  margin: 0;
  padding: 0.95rem 1rem;
  border-radius: 14px;
  background: #070a18;
  border: 1px solid rgba(110, 243, 255, 0.18);
  color: #bff7ff;
  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(139, 124, 255, 0.35);
  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: 50%;
  display: grid;
  place-items: center;
  background: rgba(139, 124, 255, 0.12);
  border: 1px solid rgba(139, 124, 255, 0.35);
  color: var(--violet);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.74rem;
}

.recommend-card .badge {
  display: inline-flex;
  margin-bottom: 0.65rem;
  padding: 0.22rem 0.65rem;
  border-radius: 999px;
  background: rgba(93, 255, 176, 0.12);
  color: var(--ok);
  border: 1px solid rgba(93, 255, 176, 0.28);
  font-size: 0.8rem;
}

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

.step-label {
  display: inline-block;
  margin-bottom: 0.55rem;
  color: var(--neon);
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: 0.06em;
  font-size: 0.86rem;
}

.hint-box {
  border-color: rgba(255, 94, 200, 0.35);
  background:
    radial-gradient(circle at 0% 0%, rgba(255, 94, 200, 0.14), transparent 45%),
    var(--panel);
}

.hint-box strong {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--magenta);
  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(110, 243, 255, 0.28);
  background:
    radial-gradient(circle at 20% 0%, rgba(110, 243, 255, 0.2), transparent 40%),
    radial-gradient(circle at 80% 100%, rgba(255, 94, 200, 0.18), transparent 40%),
    linear-gradient(135deg, #10153a, #15103a);
  box-shadow: var(--shadow);
}

.cta-band h2 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 2.9vw, 2.1rem);
}

.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: #03040c;
  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);
}

.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(--neon); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  padding-top: 1rem;
  border-top: 1px solid rgba(160, 180, 255, 0.12);
  color: #6f7c9e;
  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(1.75rem, 3.3vw, 2.5rem);
}

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

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

.download-card {
  display: grid;
  grid-template-columns: 1.25fr 1fr auto;
  gap: 1rem;
  align-items: center;
  padding: 1.2rem 1.3rem;
}

.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);
}

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

@keyframes planetPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.02); }
}

@keyframes ringSpin {
  from { transform: translate(-50%, -50%) rotateX(72deg) rotateZ(0deg); }
  to { transform: translate(-50%, -50%) rotateX(72deg) rotateZ(360deg); }
}

@keyframes orbFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

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

  .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; }
  .space-stage { min-height: 320px; }
}