:root {
  color-scheme: light dark;
  --bg: #f6f7fb;
  --surface: rgba(255, 255, 255, .88);
  --text: #14233a;
  --muted: #647084;
  --line: rgba(20, 35, 58, .1);
  --brand: #ff613f;
  --brand-2: #ff9d52;
  --navy: #0c2c52;
  --shadow: 0 18px 55px rgba(12, 44, 82, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(circle at 8% 0%, rgba(255, 97, 63, .11), transparent 30rem),
    radial-gradient(circle at 94% 15%, rgba(255, 157, 82, .12), transparent 27rem),
    var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.8;
}

a { color: var(--brand); text-underline-offset: 3px; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1080px, calc(100% - 32px));
  margin: 16px auto 0;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  box-shadow: 0 8px 30px rgba(12, 44, 82, .06);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  text-decoration: none;
}
.brand img, .footer-brand img { border-radius: 11px; box-shadow: 0 5px 14px rgba(255, 97, 63, .2); }
.brand span { display: grid; line-height: 1.25; }
.brand strong { font-size: 17px; }
.brand small { margin-top: 3px; color: var(--muted); font-size: 11px; }
nav { display: flex; gap: 6px; }
nav a {
  padding: 8px 13px;
  border-radius: 11px;
  color: var(--muted);
  font-size: 14px;
  text-decoration: none;
}
nav a:hover, nav a[aria-current="page"] { background: rgba(255, 97, 63, .1); color: var(--brand); }

main { width: min(900px, calc(100% - 32px)); margin: 0 auto; }
.hero { padding: 100px 0 62px; text-align: center; }
.hero.compact { padding-bottom: 46px; }
.eyebrow { color: var(--brand); font-size: 12px; font-weight: 800; letter-spacing: .18em; }
.hero h1 { margin: 12px 0 14px; font-size: clamp(40px, 8vw, 68px); line-height: 1.1; letter-spacing: -.04em; }
.hero p { max-width: 720px; margin: 0 auto; color: var(--muted); font-size: clamp(16px, 2.2vw, 19px); }
.meta { display: flex; justify-content: center; gap: 18px; margin-top: 24px; color: var(--muted); font-size: 13px; }

.policy {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--surface);
  box-shadow: var(--shadow);
}
.policy section { padding: 34px 42px; border-bottom: 1px solid var(--line); }
.policy section:last-child { border-bottom: 0; }
h2 { margin: 0 0 13px; color: var(--navy); font-size: 21px; line-height: 1.35; }
h2 span { display: inline-block; min-width: 36px; color: var(--brand); font-size: 12px; letter-spacing: .06em; vertical-align: 3px; }
p { margin: 8px 0; }
.policy p { color: var(--muted); }
.notice { margin-top: 18px; padding: 15px 17px; border-left: 4px solid var(--brand); border-radius: 4px 13px 13px 4px; background: rgba(255, 97, 63, .08); color: var(--muted); }
.notice strong { display: block; margin-bottom: 3px; color: var(--text); }

.support-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.support-card {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--surface);
  box-shadow: var(--shadow);
}
.support-card.primary { grid-column: 1 / -1; }
.card-icon { display: grid; place-items: center; width: 44px; height: 44px; margin-bottom: 17px; border-radius: 14px; background: linear-gradient(135deg, var(--brand), var(--brand-2)); color: white; font-size: 22px; font-weight: 700; }
.support-card p { color: var(--muted); }
.button { display: inline-block; margin: 12px 0; padding: 11px 17px; border-radius: 13px; background: var(--brand); color: white; font-weight: 700; text-decoration: none; }
.fine { font-size: 13px; }
details { padding: 10px 0; border-bottom: 1px solid var(--line); }
details:last-child { border-bottom: 0; }
summary { cursor: pointer; font-weight: 650; }
details p { font-size: 14px; }

footer { width: min(900px, calc(100% - 32px)); margin: 64px auto 0; padding: 30px 0 44px; border-top: 1px solid var(--line); color: var(--muted); text-align: center; font-size: 13px; }
.footer-brand { display: flex; align-items: center; justify-content: center; gap: 9px; color: var(--text); font-size: 15px; }
.owner { color: var(--text); }

@media (max-width: 680px) {
  .site-header { width: calc(100% - 20px); margin-top: 10px; }
  .brand small { display: none; }
  nav a { padding: 7px 9px; font-size: 13px; }
  main { width: min(100% - 22px, 900px); }
  .hero { padding: 68px 8px 40px; }
  .meta { flex-direction: column; gap: 2px; }
  .policy { border-radius: 22px; }
  .policy section { padding: 26px 22px; }
  .support-grid { grid-template-columns: 1fr; }
  .support-card.primary { grid-column: auto; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #080b10;
    --surface: rgba(24, 27, 32, .9);
    --text: #f2f5fa;
    --muted: #a3acba;
    --line: rgba(255, 255, 255, .09);
    --navy: #f2f5fa;
    --shadow: 0 18px 55px rgba(0, 0, 0, .24);
  }
}