:root {
  --green: #1B6B48;
  --green2: #2D6A4F;
  --green-light: #E8F2EC;
  --bg: #F5F7F4;
  --card: #ffffff;
  --text: #1f2d27;
  --muted: #5b6b63;
  --radius: 16px;
  --maxw: 1080px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

/* 导航 */
.nav {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #eef1ee;
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 20px;
}
.brand { font-weight: 800; font-size: 20px; color: var(--green); letter-spacing: .5px; }
.nav-links { display: flex; gap: 24px; font-size: 15px; color: var(--muted); }
.nav-links a:hover { color: var(--green); }

/* Hero */
.hero {
  background: linear-gradient(160deg, #1B6B48 0%, #2D6A4F 60%, #38865e 100%);
  color: #fff; padding: 88px 20px 96px; text-align: center;
}
.hero-inner { max-width: 720px; margin: 0 auto; }
.eyebrow {
  font-size: 13px; letter-spacing: 2px; text-transform: uppercase;
  opacity: .85; margin-bottom: 18px;
}
.hero h1 { font-size: 44px; line-height: 1.25; font-weight: 800; margin-bottom: 20px; }
.hero-sub { font-size: 17px; opacity: .92; margin-bottom: 34px; }
.hero-cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn-primary {
  background: #fff; color: var(--green); font-weight: 700;
  padding: 13px 28px; border-radius: 999px; font-size: 16px;
  transition: transform .15s ease;
}
.btn-primary:hover { transform: translateY(-2px); }
.btn-ghost {
  border: 1px solid rgba(255,255,255,.6); color: #fff;
  padding: 13px 28px; border-radius: 999px; font-size: 16px;
}
.btn-ghost:hover { background: rgba(255,255,255,.12); }

/* 区块通用 */
.section { max-width: var(--maxw); margin: 0 auto; padding: 72px 20px; }
.section-alt { max-width: none; background: var(--green-light); }
.section-alt > * { max-width: var(--maxw); margin-left: auto; margin-right: auto; }
.section-title { font-size: 30px; font-weight: 800; text-align: center; color: var(--green); margin-bottom: 12px; }
.section-desc { text-align: center; color: var(--muted); max-width: 640px; margin: 0 auto 44px; font-size: 15px; }

/* 小程序卡片 */
.apps-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px;
}
.app-card {
  background: var(--card); border-radius: var(--radius); padding: 28px 24px;
  border: 1px solid #eef1ee; box-shadow: 0 4px 18px rgba(27,107,72,.06);
  display: flex; flex-direction: column;
}
.app-card.main { border: 2px solid var(--green); }
.app-tag {
  display: inline-block; align-self: flex-start;
  background: var(--green-light); color: var(--green);
  font-size: 12px; font-weight: 700; padding: 4px 10px; border-radius: 999px; margin-bottom: 12px;
}
.app-card h3 { font-size: 22px; margin-bottom: 10px; }
.app-desc { color: var(--muted); font-size: 14px; margin-bottom: 14px; }
.app-feat { list-style: none; margin-bottom: 18px; }
.app-feat li {
  font-size: 14px; color: var(--text); padding-left: 20px; position: relative; margin-bottom: 8px;
}
.app-feat li::before { content: "✓"; color: var(--green); position: absolute; left: 0; font-weight: 700; }

.qr-box {
  margin-top: auto; align-self: center;
  width: 130px; height: 130px; border: 2px dashed var(--green);
  border-radius: 12px; display: flex; align-items: center; justify-content: center;
  text-align: center; color: var(--green); font-size: 13px; font-weight: 600;
  background: var(--green-light);
}
.qr-box.small { width: 110px; height: 110px; }

/* 科普 */
.science-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.science-card {
  background: var(--card); border-radius: var(--radius); padding: 26px;
  border: 1px solid #eef1ee;
}
.science-card h3 { font-size: 19px; color: var(--green); margin-bottom: 10px; }
.science-card p { font-size: 14px; color: var(--muted); }

/* IP */
.ip-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; }
.ip-card {
  background: var(--card); border-radius: var(--radius); padding: 28px;
  border: 1px solid #eef1ee; box-shadow: 0 4px 18px rgba(27,107,72,.06);
  text-align: center;
}
.ip-card h3 { font-size: 20px; color: var(--green); margin-bottom: 10px; }
.ip-card p { font-size: 14px; color: var(--muted); margin-bottom: 18px; }

/* Footer */
.footer { background: #163d2c; color: #cfe3d8; padding: 40px 20px; text-align: center; }
.footer-inner { max-width: var(--maxw); margin: 0 auto; }
.footer-brand { font-size: 18px; font-weight: 700; color: #fff; margin-bottom: 10px; }
.footer-note { font-size: 13px; opacity: .8; max-width: 600px; margin: 0 auto 12px; }
.footer-icp { font-size: 13px; opacity: .7; }

/* 响应式 */
@media (max-width: 820px) {
  .apps-grid { grid-template-columns: 1fr; }
  .science-grid { grid-template-columns: 1fr; }
  .ip-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 34px; }
  .section-title { font-size: 25px; }
  .nav-links { gap: 16px; font-size: 14px; }
}