:root {
  --color-primary: #3498db;
  --color-primary-dark: #2980b9;
  --color-text: #1e293b;
  --color-muted: #64748b;
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(15, 23, 42, 0.08);
  --max: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

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

.wrap {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(248, 250, 252, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(148, 163, 184, 0.2);
}

.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 0;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--color-text);
  text-decoration: none;
}

.brand:hover {
  text-decoration: none;
  color: var(--color-primary);
}

.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--color-primary), #5dade2);
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 0.95rem;
  flex-shrink: 0;
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav a {
  color: var(--color-muted);
  font-size: 0.95rem;
  text-decoration: none;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1.15rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
}

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

.btn-primary:hover {
  background: var(--color-primary-dark);
  text-decoration: none;
  transform: translateY(-1px);
}

.btn-secondary {
  background: #e2e8f0;
  color: #334155;
}

.btn-secondary:hover {
  background: #cbd5e1;
  text-decoration: none;
  transform: translateY(-1px);
}

.hero {
  padding: 3.5rem 0 4rem;
  background: linear-gradient(180deg, #e8f4fc 0%, var(--color-bg) 55%);
}

.hero-grid {
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

@media (min-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
  }
}

.hero h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
}

.hero .tagline {
  margin: 0 0 1.25rem;
  font-size: 1.1rem;
  color: var(--color-muted);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-size: 0.9rem;
  color: var(--color-muted);
}

.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.hero-visual {
  border-radius: var(--radius);
  background: var(--color-surface);
  box-shadow: var(--shadow);
  padding: 2rem;
  min-height: 260px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  border: 1px solid rgba(148, 163, 184, 0.15);
}

.hero-visual .app-icon {
  width: 88px;
  height: 88px;
  border-radius: 20px;
  background: linear-gradient(145deg, var(--color-primary), #5dade2);
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: 1rem;
  box-shadow: 0 12px 32px rgba(52, 152, 219, 0.35);
}

.hero-visual p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--color-muted);
  max-width: 280px;
}

.section {
  padding: 3.5rem 0;
}

.section-title {
  margin: 0 0 0.5rem;
  font-size: 1.65rem;
  font-weight: 800;
  text-align: center;
}

.section-lead {
  margin: 0 auto 2.5rem;
  max-width: 560px;
  text-align: center;
  color: var(--color-muted);
  font-size: 1rem;
}

.feature-grid {
  display: grid;
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 900px) {
  .feature-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.feature-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(148, 163, 184, 0.12);
  transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 32px rgba(15, 23, 42, 0.1);
}

.feature-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
  font-weight: 700;
}

.feature-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--color-muted);
}

.feature-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(52, 152, 219, 0.12);
  color: var(--color-primary);
  display: grid;
  place-items: center;
  font-size: 1.25rem;
  margin-bottom: 0.85rem;
}

.about-block {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 2rem 2.25rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(148, 163, 184, 0.12);
  max-width: 800px;
  margin-inline: auto;
}

.about-block p {
  margin: 0 0 1rem;
  color: var(--color-text);
  font-size: 0.98rem;
}

.about-block p:last-child {
  margin-bottom: 0;
}

.cta {
  text-align: center;
  padding: 3rem 1.5rem;
  background: linear-gradient(135deg, #1e3a5f 0%, #0f172a 100%);
  color: #e2e8f0;
  border-radius: var(--radius);
  margin: 0 auto;
  max-width: var(--max);
}

.cta h2 {
  margin: 0 0 0.5rem;
  font-size: 1.5rem;
  color: #fff;
}

.cta p {
  margin: 0 0 1.5rem;
  color: #94a3b8;
  font-size: 0.98rem;
}

.qr-wrap {
  margin: 0 auto 1rem;
  width: fit-content;
  padding: 0.5rem;
  background: #fff;
  border-radius: 12px;
}

.qr-wrap img {
  display: block;
  width: 160px;
  height: 160px;
  object-fit: contain;
  border-radius: 8px;
}

.site-footer {
  padding: 2rem 0 2.5rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-muted);
}

.site-footer .company {
  margin-bottom: 0.35rem;
  color: var(--color-text);
}

.site-footer .icp {
  margin-top: 0.75rem;
  margin-bottom: 0;
}

.site-footer .icp a {
  color: var(--color-muted);
  text-decoration: none;
}

.site-footer .icp a:hover {
  color: var(--color-primary);
  text-decoration: underline;
}

@media (max-width: 720px) {
  .nav {
    display: none;
  }
}