:root{--bg:#eaf2f7;--ink:#1a2733;--accent:#1f5a7a;--muted:#4a5d6c;--card:#fff;--border:#cfdde6}*{box-sizing:border-box}body,html{margin:0;padding:0;background:var(--bg);color:var(--ink);font-family:Helvetica Neue,Arial,sans-serif;line-height:1.65}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}.site-header{display:flex;justify-content:space-between;align-items:center;padding:1rem 2rem;background:var(--card);border-bottom:1px solid var(--border);position:-webkit-sticky;position:sticky;top:0;z-index:10}.site-header .logo{font-size:1.4rem;font-weight:700}.site-header nav{display:flex;flex-wrap:wrap;gap:1.2rem;font-weight:500}main{max-width:1080px;margin:0 auto;padding:2rem 1.5rem}h1{font-size:2.4rem;margin:0 0 1rem;letter-spacing:-.01em}h2{font-size:1.7rem;margin:2.5rem 0 1rem;border-bottom:2px solid var(--border);padding-bottom:.3rem}h3{font-size:1.25rem;margin:1.5rem 0 .5rem}p{margin:.8rem 0}ol,ul{padding-left:1.5rem}li{margin:.3rem 0}.game-frame{width:100%;aspect-ratio:4/3;border:1px solid var(--border);border-radius:12px;background:#2d6a4f;overflow:hidden;margin:1rem 0 2rem;box-shadow:0 8px 24px rgba(31,90,122,.15)}.game-frame iframe{width:100%;height:100%;border:0;display:block}.feature-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));grid-gap:1rem;gap:1rem;margin:1rem 0}.feature-grid>div{padding:1.2rem;background:var(--card);border:1px solid var(--border);border-radius:10px}.feature-grid h3{margin:0 0 .4rem;font-size:1.05rem}.feature-grid p{margin:0;color:var(--muted);font-size:.95rem}table{width:100%;border-collapse:collapse;margin:1rem 0;background:var(--card)}td,th{border:1px solid var(--border);padding:.6rem .8rem;text-align:left}th{background:#f5f9fb;font-weight:600}.faq details{margin:.5rem 0;padding:.8rem 1rem;background:var(--card);border:1px solid var(--border);border-radius:8px}.faq summary{cursor:pointer;font-weight:600}.faq summary:after{content:" ▾";color:var(--muted)}.site-footer{max-width:1080px;margin:3rem auto 0;padding:2rem 1.5rem;display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));grid-gap:2rem;gap:2rem;border-top:1px solid var(--border);background:var(--card)}.site-footer ul{list-style:none;padding:0}.site-footer .copyright{grid-column:1/-1;color:var(--muted);text-align:center;font-size:.9rem}