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

:root {
  --bg: #fafafa;
  --surface: #ffffff;
  --text: #171717;
  --text-muted: #737373;
  --border: #e5e5e5;
  --accent: #f05032;
  --accent-hover: #d94528;
  --accent-soft: #fff4f0;
  --radius: 10px;
  --max-width: 1080px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Sans SC", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}

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

ul {
  list-style: none;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 250, 250, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 24px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: -0.02em;
}

.logo-img {
  height: 36px;
  width: 36px;
  display: block;
  border-radius: 8px;
  flex-shrink: 0;
}

.nav {
  display: flex;
  gap: 28px;
}

.nav a {
  font-size: 0.9375rem;
  color: var(--text-muted);
  transition: color 0.15s;
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  font-size: 0.9375rem;
  font-weight: 500;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

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

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

.btn-ghost {
  color: var(--text-muted);
}

.btn-ghost:hover {
  color: var(--text);
}

.btn-outline {
  border-color: var(--border);
  background: var(--surface);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn-lg {
  padding: 12px 24px;
  font-size: 1rem;
}

/* Demo QR popover */
.demo-wrap {
  position: relative;
  display: inline-block;
}

.qrcode-popover {
  display: none;
  position: absolute;
  top: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%);
  z-index: 200;
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-align: center;
  pointer-events: none;
}

.qrcode-popover-up {
  top: auto;
  bottom: calc(100% + 10px);
}

.qrcode-popover img {
  display: block;
  width: 160px;
  height: 160px;
  border-radius: 8px;
}

.qrcode-popover p {
  margin-top: 10px;
  font-size: 0.8125rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.demo-wrap:hover .qrcode-popover,
.demo-wrap.is-open .qrcode-popover {
  display: block;
  pointer-events: auto;
}

.qrcode-backdrop {
  position: fixed;
  inset: 0;
  z-index: 150;
  background: rgba(0, 0, 0, 0.35);
}

.qrcode-backdrop[hidden] {
  display: none;
}

@media (max-width: 768px) {
  .demo-wrap.is-open .qrcode-popover {
    position: fixed;
    top: 50%;
    left: 50%;
    bottom: auto;
    transform: translate(-50%, -50%);
    pointer-events: auto;
  }

  .demo-wrap.is-open .qrcode-popover-up {
    top: 50%;
    bottom: auto;
  }
}

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

.hero-badge {
  display: inline-block;
  margin-bottom: 20px;
  padding: 6px 14px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 100px;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
}

.hero-desc {
  max-width: 560px;
  margin: 0 auto 32px;
  font-size: 1.125rem;
  color: var(--text-muted);
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  margin-bottom: 24px;
}

.hero-note {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Sections */
.section {
  padding: 72px 0;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-align: center;
  margin-bottom: 8px;
}

.section-desc {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 48px;
}

/* Features */
.features {
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
}

.feature-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 0.9375rem;
  color: var(--text-muted);
}

.feature-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  margin-bottom: 16px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: var(--radius);
}

/* Stats */
.stats-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 48px 80px;
}

.stat {
  text-align: center;
}

.stat-value {
  display: block;
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--accent);
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Services */
.services {
  background: var(--surface);
  border-top: 1px solid var(--border);
}

.service-list {
  max-width: 720px;
  margin: 0 auto;
}

.service-item {
  display: flex;
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid var(--border);
}

.service-item:first-child {
  border-top: 1px solid var(--border);
}

.service-step {
  flex-shrink: 0;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.4;
}

.service-item h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.service-item p {
  font-size: 0.9375rem;
  color: var(--text-muted);
}

.services-cta {
  text-align: center;
  margin-top: 48px;
}

/* FAQ */
.faq-inner {
  max-width: 640px;
  margin: 0 auto;
}

.faq-list {
  margin-top: 40px;
}

.faq-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}

.faq-item:first-child {
  border-top: 1px solid var(--border);
}

.faq-item dt {
  font-weight: 600;
  margin-bottom: 8px;
}

.faq-item dd {
  font-size: 0.9375rem;
  color: var(--text-muted);
}

/* CTA Banner */
.cta-banner {
  padding: 64px 0;
  background: #1c1917;
  color: #fff;
}

.cta-inner {
  text-align: center;
}

.cta-inner h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.cta-inner p {
  color: #a8a29e;
  margin-bottom: 28px;
}

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

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

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

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.footer-copy {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.footer-nav {
  display: flex;
  gap: 24px;
}

.footer-nav a {
  font-size: 0.875rem;
  color: var(--text-muted);
}

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

/* Mobile */
@media (max-width: 768px) {
  .nav,
  .header-actions {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

  .header.nav-open .nav,
  .header.nav-open .header-actions {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    padding: 20px 24px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    gap: 16px;
  }

  .header.nav-open .header-inner {
    flex-wrap: wrap;
  }

  .hero {
    padding: 48px 0 64px;
  }

  .section {
    padding: 48px 0;
  }

  .service-item {
    gap: 16px;
  }
}