:root { color-scheme: light; font-family: system-ui, "Microsoft YaHei", sans-serif; color: #172c3b; background: #f5f8fa; }
* { box-sizing: border-box; }
body { margin: 0; }
a { color: inherit; text-decoration: none; }
a:hover { text-decoration: underline; }
.site-header { max-width: 1120px; margin: auto; padding: 26px 24px; display: flex; justify-content: space-between; align-items: center; }
.brand { font-weight: 750; font-size: 22px; }
nav { display: flex; gap: 24px; font-size: 14px; }
main { max-width: 1120px; margin: auto; padding: 0 24px; }
.hero { padding: 88px 0 56px; max-width: 800px; }
.eyebrow { color: #137d70; font-weight: 650; letter-spacing: 3px; }
h1 { font-size: clamp(32px, 5vw, 56px); line-height: 1.2; margin: 20px 0; }
.intro, .card p, .about p { color: #536674; line-height: 1.8; }
.intro { font-size: 19px; }
button { margin-top: 18px; padding: 14px 24px; border: 0; border-radius: 8px; background: #137d70; color: white; font: inherit; cursor: pointer; }
button:hover { background: #0e6359; }
:focus-visible { outline: 3px solid #e0a635; outline-offset: 4px; }
.message { min-height: 24px; color: #137d70; }
.features { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.card { padding: 28px; background: white; border: 1px solid #dfe8ed; border-radius: 12px; }
.card span { color: #137d70; font-size: 14px; }
.card h2 { font-size: 20px; margin-top: 22px; }
.about { padding: 56px 0; }
.about h2 { font-size: 24px; }
footer { max-width: 1120px; margin: auto; padding: 24px; border-top: 1px solid #dfe8ed; color: #536674; font-size: 14px; }
@media (max-width: 700px) { .features { grid-template-columns: 1fr; } .hero { padding-top: 48px; } }