:root {
  color-scheme: dark;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  background: #020a23;
  color: #edf6ff;
}

* { box-sizing: border-box; }
body { margin: 0; line-height: 1.8; background: radial-gradient(circle at 85% 0%, #0b57b5 0, transparent 30%), #020a23; }
.hero { min-height: 340px; padding: 78px 24px 56px; text-align: center; background: linear-gradient(135deg, #06194b, #082b77 55%, #075cab); border-bottom: 2px solid #f7c95d; }
.eyebrow { margin: 0; color: #f7c95d; font-weight: 800; letter-spacing: .18em; font-size: .78rem; }
h1 { margin: 10px 0 0; color: #ffd15c; font-size: clamp(2.2rem, 8vw, 4.7rem); font-weight: 900; letter-spacing: .06em; text-shadow: 0 4px 0 #4d2800, 0 0 24px #ffd15c77; }
.lead { margin: 8px 0 0; color: #fff; font-size: 1.18rem; font-weight: 800; }
.description { margin: 2px 0; color: #c8e9ff; }
main { width: min(900px, calc(100% - 32px)); margin: 0 auto; padding: 38px 0 60px; }
section { margin: 20px 0; padding: 24px; border: 1px solid #2c5c9e; border-radius: 18px; background: #071738cc; box-shadow: 0 12px 28px #0004; }
h2 { margin-top: 0; color: #ffd15c; font-size: 1.35rem; }
h3 { margin-bottom: 6px; color: #c8e9ff; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 14px; }
article { padding: 10px 18px; border-radius: 12px; background: #0c2654; }
.note { color: #f9d77c; font-size: .94rem; }
.steps strong { color: #7ad8ff; }
.games { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 4px 24px; padding-left: 22px; }
footer { padding: 28px; text-align: center; color: #8ba8d3; border-top: 1px solid #23477e; }
footer p { margin: 4px 0; }
a { color: #ffd15c; }
@media (max-width: 520px) { section { padding: 18px; } .hero { min-height: 290px; padding-top: 58px; } }