:root { color-scheme: light dark; --text: #1d1d1f; --muted: #6e6e73; --bg: #fbfbfd; --card: #fff; --line: #d2d2d7; --accent: #0071e3; --hero1: #e8f1ff; --hero2: #fbfbfd; }
@media (prefers-color-scheme: dark) { :root { --text: #f5f5f7; --muted: #a1a1a6; --bg: #000; --card: #1c1c1e; --line: #38383a; --accent: #2997ff; --hero1: #0b2346; --hero2: #000; } }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); font: 17px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.hero { position: relative; text-align: center; padding: 64px 16px 48px; background: linear-gradient(180deg, var(--hero1), var(--hero2)); }
.icon { width: 128px; height: 128px; filter: drop-shadow(0 12px 24px rgba(0, 113, 227, .3)); }
.hero h1 { font-size: 48px; line-height: 1.1; margin: 16px 0 0; letter-spacing: -.02em; }
.tagline { font-size: 22px; font-weight: 600; color: var(--accent); margin: 4px 0 16px; }
.lead { font-size: 19px; color: var(--muted); margin: 0; }

main { max-width: 880px; margin: 0 auto; padding: 0 16px 48px; }
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 8px 0 56px; }
.features div { background: var(--card); border: 1px solid var(--line); border-radius: 20px; padding: 20px; }
.features span { font-size: 28px; }
.features h3 { margin: 8px 0 4px; font-size: 19px; }
.features p { margin: 0; color: var(--muted); font-size: 15px; }

h2 { font-size: 32px; text-align: center; margin: 0 0 20px; }
details { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 0 18px; margin: 10px 0; }
summary { cursor: pointer; font-weight: 600; padding: 14px 0; }
details[open] summary { border-bottom: 1px solid var(--line); margin-bottom: 8px; }
details p, details ul { margin: 8px 0 14px; }
li { margin: 4px 0; }

.contact { text-align: center; margin-top: 32px; }
.contact p { color: var(--muted); margin: 0 0 12px; }
.button { display: inline-block; background: var(--accent); color: #fff; font-weight: 600; padding: 12px 24px; border-radius: 999px; }
.button:hover { text-decoration: none; opacity: .9; }

footer { text-align: center; color: var(--muted); font-size: 14px; padding: 24px 16px 40px; border-top: 1px solid var(--line); }
footer p { margin: 8px 0 0; }

@media (max-width: 480px) { .hero h1 { font-size: 40px; } .icon { width: 104px; height: 104px; } }