:root{color-scheme:light dark;--bg:#fafaf9;--card:#fff;--line:#e7e9ed;--fg:#0f172a;--mut:#64748b;--ac:#2563eb;--on:#fff;--soft:#f3f4f6}
@media(prefers-color-scheme:dark){:root{--bg:#0b0d10;--card:#14171c;--line:#252a33;--fg:#f1f5f9;--mut:#9aa6b8;--ac:#6d9bff;--on:#0b0d10;--soft:#1a1e25}}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:17px/1.6 -apple-system,BlinkMacSystemFont,"SF Pro Text","Segoe UI",Roboto,Helvetica,Arial,sans-serif;overflow-wrap:anywhere}
:lang(ja){font-family:-apple-system,"Hiragino Sans","Yu Gothic","Noto Sans JP",sans-serif}
:lang(ko){font-family:-apple-system,"Apple SD Gothic Neo","Malgun Gothic","Noto Sans KR",sans-serif}
:lang(zh-Hans){font-family:-apple-system,"PingFang SC","Microsoft YaHei","Noto Sans SC",sans-serif}
:lang(zh-Hant){font-family:-apple-system,"PingFang TC","Microsoft JhengHei","Noto Sans TC",sans-serif}
:lang(th){font-family:-apple-system,"Thonburi","Leelawadee UI","Noto Sans Thai",sans-serif}
:lang(ja),:lang(ko),:lang(zh-Hans),:lang(zh-Hant),:lang(th){line-height:1.75}
:lang(ar),:lang(he),:lang(hi),:lang(th){--ls:0}
a{color:var(--ac)}a:focus-visible{outline:3px solid var(--ac);outline-offset:3px;border-radius:4px}
.skip{position:absolute;inset-inline-start:-9999px;top:8px;background:var(--bg);color:var(--fg);padding:10px 16px;z-index:10}.skip:focus{inset-inline-start:12px}
.wrap{max-width:880px;margin:0 auto;padding-inline:max(20px,env(safe-area-inset-left)) max(20px,env(safe-area-inset-right))}
header.top{border-bottom:1px solid var(--line)}
header.top .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px 24px;flex-wrap:wrap;min-height:60px;padding-block:6px}
.brand{font-weight:600;font-size:19px;letter-spacing:-.3px;color:var(--fg);text-decoration:none}
nav ul{display:flex;gap:4px 20px;list-style:none;margin:0;padding:0;flex-wrap:wrap}
nav a{color:var(--mut);text-decoration:none;font-size:15px}nav a:hover,nav a[aria-current]{color:var(--fg)}
h1{font-size:clamp(30px,6vw,50px);line-height:1.15;letter-spacing:var(--ls,-1.2px);margin:0 0 16px;font-weight:600}
h2{font-size:clamp(22px,3.4vw,28px);letter-spacing:var(--ls,-.5px);line-height:1.25;margin:40px 0 12px}
h3{font-size:18px;margin:0 0 4px;line-height:1.35}
.hero{padding:56px 0 24px}
.icon{display:block;width:88px;height:88px;border-radius:20px;margin:0 0 24px}
.lead{font-size:clamp(18px,2.4vw,21px);color:var(--mut);max-width:640px;margin:0}
.eyebrow{margin:0 0 12px;color:var(--ac);font-weight:600;font-size:15px}
.cta{display:flex;align-items:center;gap:12px 20px;flex-wrap:wrap;margin:28px 0 0}
.btn{display:inline-block;background:var(--ac);color:var(--on);padding:12px 22px;border-radius:12px;font-weight:600;text-decoration:none;font-size:17px}
.btn:hover{opacity:.9}.btn:focus-visible{outline-color:var(--fg)}
.dev{color:var(--mut);font-size:15px}
main section{padding:8px 0 16px}
.list{list-style:none;margin:0;padding:0;border-top:1px solid var(--line)}
.list li{padding:16px 0;border-bottom:1px solid var(--line)}
.list p{margin:0;color:var(--mut)}
.prose{padding:24px 0 64px;max-width:720px}.prose h1{font-size:clamp(28px,5vw,40px)}
.prose li{margin:4px 0}.muted{color:var(--mut)}
.crumbs{padding-top:20px;font-size:14px;color:var(--mut)}
.crumbs ol{display:flex;flex-wrap:wrap;gap:2px 8px;list-style:none;margin:0;padding:0}
.crumbs li+li::before{content:"/";margin-inline-end:8px}
.crumbs a{color:var(--mut)}
.legal-note{margin:0 0 20px;padding:10px 14px;background:var(--soft);border:1px solid var(--line);border-radius:8px;font-size:15px}
footer{border-top:1px solid var(--line);margin-top:32px;padding:24px 0 40px;color:var(--mut);font-size:14px}
footer ul{display:flex;gap:4px 20px;list-style:none;margin:0 0 10px;padding:0;flex-wrap:wrap}footer a{color:var(--mut)}
footer .langs{gap:2px 14px;margin:16px 0 0}footer .langs a[aria-current]{color:var(--fg);font-weight:600;text-decoration:none}
footer .lh{margin:16px 0 0;font-weight:600}