:root{color-scheme:light;--bg:#f5f8fc;--card:#ffffff;--text:#0f172a;--muted:#526176;--line:#dbe4ef;--blue:#0f62fe;--blue-dark:#0b4dcc;--soft-blue:#eef5ff;--soft-green:#eaf8f0;--soft-amber:#fff8e7;--shadow:0 14px 40px rgba(15,23,42,.07)}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.68}
a{color:var(--blue);text-decoration-thickness:1px;text-underline-offset:3px}
a:hover{color:var(--blue-dark)}
.site-header{position:sticky;top:0;z-index:20;border-bottom:1px solid var(--line);background:rgba(255,255,255,.96);backdrop-filter:blur(10px)}
.header-inner{max-width:1120px;margin:auto;padding:14px 22px;display:flex;align-items:center;justify-content:space-between;gap:18px}
.brand{display:flex;align-items:center;gap:9px;color:var(--text);font-weight:900;text-decoration:none;font-size:1.15rem}
.brand svg{width:30px;height:22px;flex:0 0 auto}
.site-nav{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px 16px;font-size:.9rem;font-weight:750}
.site-nav a{color:#334155;text-decoration:none}
.site-nav a:hover{color:var(--blue)}
.hero{border-bottom:1px solid var(--line);background:linear-gradient(135deg,#e8f2ff 0%,#f8fbff 56%,#eefaf5 100%)}
.hero-inner{max-width:1060px;margin:auto;padding:58px 24px 50px}
.eyebrow{font-size:.78rem;font-weight:900;letter-spacing:.13em;text-transform:uppercase;color:var(--blue)}
h1{max-width:900px;margin:.65rem 0 1rem;font-size:clamp(2.15rem,5vw,3.65rem);line-height:1.06;letter-spacing:-.045em}
.hero p{max-width:820px;margin:.65rem 0;color:#3d4d62;font-size:1.08rem}
.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:24px}
.button{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:11px 17px;border:1px solid var(--blue);border-radius:10px;font-weight:850;text-decoration:none}
.button-primary{background:var(--blue);color:#fff;box-shadow:0 8px 22px rgba(15,98,254,.2)}
.button-primary:hover{background:var(--blue-dark);color:#fff}
.button-secondary{background:#fff;color:var(--blue)}
.hero-note{margin-top:12px!important;font-size:.9rem!important;color:#617086!important}
.page{max-width:1060px;margin:0 auto;padding:34px 24px 64px}
.content-grid{display:grid;grid-template-columns:minmax(0,1fr) 255px;gap:28px;align-items:start}
.article{min-width:0;padding:clamp(24px,4vw,44px);border:1px solid var(--line);border-radius:18px;background:var(--card);box-shadow:var(--shadow)}
.article>section:first-child h2{margin-top:0}
.article h2{margin:2.15rem 0 .75rem;font-size:1.55rem;line-height:1.22;letter-spacing:-.02em}
.article h3{margin:1.45rem 0 .45rem;font-size:1.12rem}
.article p,.article li{color:#334155}
.article li{margin:.48rem 0}
.article strong{color:#0f172a}
.lead{font-size:1.08rem;line-height:1.75}
.formula{overflow:auto;margin:1rem 0;padding:14px 16px;border-radius:12px;background:#0f172a;color:#eef6ff;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
.callout{margin:1.35rem 0;padding:16px 18px;border-radius:14px}
.callout-blue{border:1px solid #cfe1ff;background:var(--soft-blue)}
.callout-green{border:1px solid #bfe7cf;background:var(--soft-green)}
.callout-amber{border:1px solid #f4d98c;background:var(--soft-amber)}
.article table{width:100%;margin:1rem 0 1.5rem;border-collapse:collapse;font-size:.94rem}
.article th,.article td{padding:11px 12px;border:1px solid var(--line);text-align:left;vertical-align:top}
.article th{background:#f0f5fb;color:#1e293b}
.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin:1.1rem 0 1.5rem}
.stat{padding:14px;border:1px solid var(--line);border-radius:13px;background:#f8fbff}
.stat span{display:block;color:#64748b;font-size:.75rem;font-weight:850;letter-spacing:.05em;text-transform:uppercase}
.stat strong{display:block;margin-top:.25rem;font-size:1.22rem}
.steps{counter-reset:steps;list-style:none;padding:0}
.steps li{position:relative;margin:1rem 0;padding-left:2.6rem;counter-increment:steps}
.steps li:before{content:counter(steps);position:absolute;top:.05rem;left:0;display:grid;width:1.8rem;height:1.8rem;place-items:center;border-radius:999px;background:var(--blue);color:#fff;font-size:.82rem;font-weight:900}
.figure{margin:1.4rem 0;padding:14px;border:1px solid var(--line);border-radius:16px;background:#fbfdff}
.figure img{display:block;width:100%;height:auto;border-radius:10px}
.figure figcaption{margin-top:10px;color:#64748b;font-size:.86rem;line-height:1.55}
.cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:1.2rem 0}
.card{padding:18px;border:1px solid var(--line);border-radius:15px;background:#fff;color:inherit;text-decoration:none;box-shadow:0 8px 24px rgba(15,23,42,.04)}
.card:hover{border-color:#a9c7f7;transform:translateY(-1px)}
.card h3{margin:0 0 .45rem;font-size:1.05rem}
.card p{margin:0;color:#526176;font-size:.92rem}
.toc{position:sticky;top:82px;padding:18px;border:1px solid var(--line);border-radius:16px;background:#fff}
.toc h2{margin:0 0 .7rem;font-size:1rem}
.toc a{display:block;padding:5px 0;font-size:.9rem;text-decoration:none}
.source-list{padding-left:1.2rem}
.site-footer{border-top:1px solid var(--line);background:#fff}
.footer-inner{max-width:1060px;margin:auto;padding:28px 24px 36px}
.footer-nav{display:flex;flex-wrap:wrap;gap:8px 18px;font-size:.9rem;font-weight:700}
.footer-note{max-width:860px;margin-top:15px;color:#64748b;font-size:.86rem}
.small{font-size:.9rem;color:#64748b}
@media(max-width:860px){.content-grid{grid-template-columns:1fr}.toc{position:static;order:-1}.cards{grid-template-columns:1fr}.header-inner{align-items:flex-start}.site-nav{gap:7px 12px}}
@media(max-width:620px){.header-inner{display:block}.site-nav{justify-content:flex-start;margin-top:10px}.hero-inner{padding:42px 18px 38px}.page{padding:22px 15px 48px}.article{border-radius:14px}.stats{grid-template-columns:1fr}.article table{display:block;overflow-x:auto}.hero-actions .button{width:100%}}
html.night-mode{color-scheme:dark;--bg:#020617;--card:#07111f;--text:#e8f1ff;--muted:#a7b5c8;--line:#22314a;--blue:#76a9ff;--blue-dark:#9ec0ff;--soft-blue:#0c203d;--soft-green:#0d261a;--soft-amber:#2d220b;--shadow:0 14px 40px rgba(0,0,0,.25)}
html.night-mode body{background:var(--bg);color:var(--text)}
html.night-mode .site-header,html.night-mode .site-footer,html.night-mode .toc,html.night-mode .card{background:#07111f}
html.night-mode .site-nav a,html.night-mode .hero p,html.night-mode .article p,html.night-mode .article li,html.night-mode .card p{color:#b9c7d9}
html.night-mode .hero{background:linear-gradient(135deg,#081b34,#07111f 56%,#0a2018)}
html.night-mode .button-secondary{background:#07111f}
html.night-mode .article strong{color:#eef6ff}
html.night-mode .article th{background:#0d1c31;color:#dce9fb}
html.night-mode .stat,html.night-mode .figure{background:#0b1829}
html.night-mode .brand{color:#e8f1ff}