:root{--brand:#2f6df6;--apricot:#f08a24;--ink:#1c2430;--muted:#5a6675;--bg:#fbf7f0;--card:#fff;--line:#ececec}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
body{margin:0;font:17px/1.65 -apple-system,Segoe UI,Roboto,sans-serif;color:var(--ink);background:var(--bg)}
.topbar{position:sticky;top:0;z-index:5;display:flex;justify-content:space-between;align-items:center;gap:8px 16px;padding:8px 16px;background:#fff;border-bottom:1px solid var(--line);flex-wrap:wrap}
.brand{font-weight:700;color:var(--brand);text-decoration:none}
.hint{margin:0;color:var(--muted);font-size:12.5px}
main{max-width:760px;margin:0 auto;padding:20px 16px 60px}
h1{font-size:24px;line-height:1.3}.lead{color:var(--muted)}
.breadcrumb{color:var(--muted);font-size:14px;margin-bottom:8px}.breadcrumb a{color:var(--brand)}
.article{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px 18px;margin:14px 0}
.article-title{font-weight:600;margin:0 0 8px}
.part{margin:8px 0}.part-no{color:var(--apricot);font-weight:700}
.part .hy{font-size:1.05em;margin:0 0 2px}.part .ru{color:#6b7785;margin:0 0 4px}
h1 .hy,h1 .ru,.article-title .hy,.article-title .ru{display:block}
.seg{cursor:pointer;border-radius:5px;padding:1px 2px;transition:background .12s,color .12s;outline:none}
.seg:hover,.seg:focus-visible{background:#fdebcf}
.seg.hl{background:var(--apricot);color:#fff}
.part:hover .ru{color:#2b3a4a}
.toc{list-style:none;padding:0}.toc li{margin:6px 0}
.toc a{display:block;background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px 14px;text-decoration:none;color:var(--ink)}
.toc .ch-num{display:block;color:var(--brand);font-size:13px;font-weight:700}
.toc .hy{color:var(--muted);font-size:.95em}
.chapter-nav{display:flex;justify-content:space-between;margin-top:20px;gap:12px}.chapter-nav a{color:var(--brand);text-decoration:none}
.preamble{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px}
.site-footer{max-width:760px;margin:0 auto;padding:20px 16px 40px;color:var(--muted);font-size:13px}