:root{--bg:#EEF2F1;--surface:#fff;--ink:#17222B;--muted:#56636E;--line:#D6DEDD;--acc:#0B7A6A;--acc-soft:#DDF1EC;color-scheme:light}
@media (prefers-color-scheme:dark){:root{--bg:#10161A;--surface:#182127;--ink:#E6EDF0;--muted:#9AA9B3;--line:#2C3A42;--acc:#3CC2A8;--acc-soft:#15332D;color-scheme:dark}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:"Hiragino Sans","BIZ UDPGothic","Yu Gothic",sans-serif;font-size:16px;line-height:1.8;padding-inline:16px;padding-block:24px 56px}
main{max-width:680px;margin:0 auto;display:flex;flex-direction:column;gap:18px}
h1{font-family:"Hiragino Maru Gothic ProN","Hiragino Sans",sans-serif;font-size:26px;line-height:1.35;margin:0;text-wrap:balance}
h2{font-family:"Hiragino Maru Gothic ProN","Hiragino Sans",sans-serif;font-size:18px;margin:0 0 6px;color:var(--acc)}
p{margin:0}
.sub{color:var(--muted);font-size:14px}
section{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:16px 18px}
section p+p,section ul+p,section p+ul{margin-top:8px}
ul{margin:0;padding-left:1.3em}
dl{margin:0;display:flex;flex-direction:column;gap:12px}
dt{font-weight:700}
dd{margin:2px 0 0}
nav{display:flex;gap:14px;flex-wrap:wrap;font-size:14px}
a{color:var(--acc)}
footer{color:var(--muted);font-size:13px;text-align:center}
.btn{display:block;text-align:center;font-weight:700;border-radius:12px;padding:13px;background:var(--acc);color:#fff;text-decoration:none;margin-top:12px}
@media (prefers-color-scheme:dark){.btn{color:#0E1418}}