:root {
  --bg: #0a0a0b;
  --bg-elevated: #111113;
  --bg-card: #161618;
  --border: rgba(255, 255, 255, 0.08);
  --text: #f4f4f5;
  --text-muted: #a1a1aa;
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --accent-soft: rgba(99, 102, 241, 0.12);
  --green: #22c55e;
  --radius: 12px;
  --max: 1120px;
  --font: "Inter", "SF Pro Display", -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

.container {
  width: min(var(--max), calc(100% - 48px));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  background: rgba(10, 10, 11, 0.85);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), #a855f7);
  display: grid;
  place-items: center;
  font-size: 14px;
  font-weight: 700;
}

.logo-en {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 14px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav a {
  color: var(--text-muted);
  font-size: 14px;
  transition: color 0.15s;
}

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

.nav-cta {
  padding: 8px 16px;
  border-radius: 8px;
  background: var(--text);
  color: var(--bg) !important;
  font-weight: 500;
}

.nav-cta:hover {
  opacity: 0.9;
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 24px;
  cursor: pointer;
}

/* Hero */
.hero {
  padding: 96px 0 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: -40% -20% auto;
  height: 600px;
  background: radial-gradient(ellipse at center, var(--accent-soft), transparent 70%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.hero-badge .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green);
}

.hero h1 {
  font-size: clamp(40px, 6vw, 64px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin: 0 0 20px;
}

.hero h1 .en {
  display: block;
  font-size: 0.45em;
  font-weight: 500;
  color: var(--text-muted);
  margin-top: 8px;
  letter-spacing: 0.02em;
}

.hero-lead {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto 36px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 500;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
}

.btn-secondary {
  background: var(--bg-card);
  border-color: var(--border);
  color: var(--text);
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.18);
}

.hero-meta {
  margin-top: 48px;
  font-size: 13px;
  color: var(--text-muted);
}

/* Sections */
section {
  padding: 80px 0;
}

.section-label {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(28px, 4vw, 36px);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 16px;
}

.section-desc {
  color: var(--text-muted);
  max-width: 560px;
  margin-bottom: 48px;
}

/* Features */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  padding: 28px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
}

.feature-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--accent-soft);
  display: grid;
  place-items: center;
  font-size: 20px;
  margin-bottom: 16px;
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.feature-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 14px;
}

/* Workflow */
.workflow {
  background: var(--bg-elevated);
  border-block: 1px solid var(--border);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  counter-reset: step;
}

.step {
  position: relative;
  padding-top: 8px;
}

.step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 12px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

.step p {
  margin: 0;
  font-size: 14px;
  color: var(--text-muted);
}

/* Download */
.download-box {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.download-card {
  padding: 32px;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid var(--border);
}

.download-card h3 {
  margin: 0 0 4px;
  font-size: 20px;
}

.download-card .platform {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 20px;
}

.download-card .version {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--accent-soft);
  color: var(--accent-hover);
  font-size: 12px;
  font-weight: 500;
  margin-bottom: 20px;
}

/* Footer */
.site-footer {
  padding: 48px 0 32px;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 24px;
  align-items: flex-start;
}

.footer-brand p {
  margin: 8px 0 0;
  color: var(--text-muted);
  font-size: 14px;
  max-width: 320px;
}

.footer-links {
  display: flex;
  gap: 32px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 14px;
}

.footer-links a:hover {
  color: var(--text);
}

.footer-bottom {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  font-size: 13px;
  color: var(--text-muted);
}

.icp-pending {
  color: #f59e0b;
}

@media (max-width: 900px) {
  .features-grid,
  .steps {
    grid-template-columns: 1fr 1fr;
  }

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

@media (max-width: 640px) {
  .nav {
    display: none;
  }

  .nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    padding: 16px 24px 24px;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
  }

  .menu-toggle {
    display: block;
  }

  .features-grid,
  .steps {
    grid-template-columns: 1fr;
  }

  .hero {
    padding: 64px 0 56px;
  }
}