:root{--bg:#f3f4f7;--surface:#fff;--sunk:#eceef3;--ink:#18202e;--muted:#5d6779;--line:#dfe3ea;--ai:#24407f;--ai-soft:#e4e9f6;--shu:#c8432b;--ok:#25804f;--ok-soft:#e1f2e8;--hl:#fff1b8;color-scheme:light dark}
@media (prefers-color-scheme:dark){:root{--bg:#11141b;--surface:#191e28;--sunk:#222836;--ink:#e7eaf1;--muted:#9aa4b6;--line:#2b3242;--ai:#9db2ff;--ai-soft:#25304d;--shu:#ff7b60;--ok:#5cc98b;--ok-soft:#1b3326;--hl:#4a3f12}}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 system-ui,-apple-system,'Segoe UI',Roboto,sans-serif}
.jp{font-family:'Hiragino Sans','Noto Sans JP','Yu Gothic','Meiryo',sans-serif}
a{color:var(--ai)}
.wrap{max-width:860px;margin:0 auto;padding:0 16px}
.top{background:var(--surface);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:5}
.top .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:52px}
.logo{display:flex;align-items:center;gap:8px;text-decoration:none;color:var(--ink);font-size:18px}
.top nav{display:flex;gap:4px;flex-wrap:wrap}
.top nav a{padding:6px 10px;border-radius:8px;text-decoration:none;color:var(--ink);font-size:14px}
.top nav a:hover{background:var(--sunk)}.top nav a.app{background:var(--ai);color:var(--surface);font-weight:600}
main{padding-bottom:32px}
.bc{font-size:13px;color:var(--muted);margin:14px 0 0}.bc a{text-decoration:none}
h1{font-size:30px;line-height:1.25;margin:10px 0 6px}h2{font-size:19px;margin:0 0 10px}h3{font-size:15px;margin:0 0 6px;color:var(--muted)}
section{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:16px;margin:14px 0}
.lead{font-size:18px;margin:4px 0 10px}.muted{color:var(--muted)}small{color:var(--muted)}
.tags{display:flex;flex-wrap:wrap;gap:6px;margin:8px 0}
.tag{background:var(--ai-soft);color:var(--ai);border-radius:999px;padding:2px 10px;font-size:13px}.tag.alt{background:var(--sunk);color:var(--ink)}.tag.src{background:transparent;border:1px solid var(--line);color:var(--muted)}
.lvl{display:inline-block;border-radius:6px;padding:0 8px;font-size:13px;font-weight:700;color:#fff;vertical-align:middle;background:#777}
.l5{background:#2e9b61}.l4{background:#3a8fc4}.l3{background:#c98a1b}.l2{background:#d0592b}.l1{background:#a8343f}
.tg{font-style:normal;background:var(--ai);color:var(--surface);border-radius:5px;padding:1px 6px;font-size:14px;font-weight:700}
.pl{font-style:normal;color:var(--shu);font-weight:700;padding:0 4px}
ul.fo{list-style:none;padding:0;margin:0;display:grid;gap:8px}ul.fo li{background:var(--sunk);border-radius:8px;padding:8px 12px;font-size:17px}
ol.ex{padding-left:22px;margin:0}ol.ex li{margin:0 0 12px}ol.ex .jp{font-size:19px;line-height:2}.uz{color:var(--muted)}
mark{background:var(--hl);color:inherit;border-radius:4px;padding:0 2px}
rt{font-size:.55em}
details{border-top:1px solid var(--line);padding:8px 0}details:first-of-type{border-top:0}
summary{cursor:pointer;font-size:17px;padding:2px 0}
.opts{margin:8px 0;padding-left:22px}.opts li.ok{color:var(--ok);font-weight:700}.why{margin:4px 0;color:var(--muted)}.star{color:var(--shu)}
.ctaw{text-align:center;margin:18px 0}.cta{display:inline-block;background:var(--ai);color:var(--surface);text-decoration:none;padding:12px 22px;border-radius:12px;font-weight:700}
.links{padding-left:18px;margin:6px 0}
.grid{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:8px}
.grid a{display:block;background:var(--sunk);border-radius:10px;padding:8px 12px;text-decoration:none;color:var(--ink);height:100%}.grid a span{font-size:17px;font-weight:600;display:block}.grid small{display:block;line-height:1.35}
.kg{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(52px,1fr));gap:6px}.kg a{display:block;text-align:center;font-size:28px;line-height:48px;background:var(--sunk);border-radius:10px;text-decoration:none;color:var(--ink)}
.khead{display:flex;gap:18px;align-items:center;flex-wrap:wrap;margin-top:10px}.kbig{font-size:110px;line-height:1.1;background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:6px 24px}
.cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:14px}.rd{list-style:none;padding:0;margin:0}.rd li{margin:0 0 8px}.rd .w{display:block}
.strokes{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(64px,1fr));gap:8px}.strokes li{text-align:center}
.strokes svg{width:100%;aspect-ratio:1;background:var(--sunk);border-radius:8px;stroke-width:4}
.strokes .done{stroke:var(--muted)}.strokes .cur{stroke:var(--shu);stroke-width:5}
.words{list-style:none;padding:0;margin:0}.words li{border-top:1px solid var(--line);padding:10px 0}.words li:first-child{border-top:0}
.wd{font-size:21px;font-weight:700;text-decoration:none}.rdg{color:var(--muted)}.exs{margin-top:4px}.exs .jp{font-size:17px}
.pn{display:flex;justify-content:space-between;gap:10px;margin:18px 0}.pn a{background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:8px 14px;text-decoration:none}
footer{border-top:1px solid var(--line);color:var(--muted);font-size:14px;padding:14px 0 28px}
@media (max-width:520px){h1{font-size:25px}.kbig{font-size:84px}}