:root{--ink:#0c1226;--ink2:#171f3d;--paper:#f6f1e6;--card:#fffdf8;--line:#dcd2bb;--brass:#c99524;--brass2:#f2c14e;
--mint:#12a37a;--mintbg:#e1f5ee;--tx:#1d2236;--mut:#5b6178;--r:14px}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:74px}
body{margin:0;background:var(--paper);color:var(--tx);font:16px/1.65 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
-webkit-text-size-adjust:100%}
img{max-width:100%;height:auto;display:block}
a{color:#0b6b52;text-underline-offset:3px}
.bv-wrap{width:100%;max-width:1180px;margin:0 auto;padding:0 18px}
.bv-head{position:sticky;top:0;z-index:50;background:var(--ink);color:#fff;border-bottom:2px solid var(--brass)}
.bv-head__bar{display:flex;flex-wrap:wrap;align-items:center;gap:10px;min-height:58px;padding-top:8px;padding-bottom:8px}
.bv-logo{display:block;line-height:0}
.bv-logo{width:132px}
.bv-logo img{width:132px;height:auto}
.bv-burger{margin-left:auto;background:transparent;border:1px solid #4b557e;color:#fff;border-radius:10px;
padding:8px 14px;font-size:14px;font-weight:600;line-height:1;cursor:pointer}
.bv-nav{display:none;flex:0 0 100%;width:100%;padding:6px 0 12px}
.bv-nav--open{display:block;flex:0 0 100%;width:100%}
.bv-nav ul{list-style:none;margin:0 0 10px;padding:0}
.bv-nav li a{display:block;padding:11px 4px;color:#e9ecf7;text-decoration:none;border-bottom:1px solid #263056;font-weight:600}
.bv-cta{display:inline-block;background:linear-gradient(180deg,var(--brass2),var(--brass));color:#1b1405;font-weight:800;
text-decoration:none;border-radius:999px;padding:11px 22px;box-shadow:0 2px 0 #8a6414;text-align:center}
.bv-cta:hover{filter:brightness(1.06)}
.bv-head__cta{display:none}
.bv-nav__cta{display:block;margin-top:12px}
.bv-progress{height:3px;background:#1c2447}
.bv-progress i{display:block;height:100%;width:0;background:var(--mint)}
.bv-band{background:var(--ink2);color:#f3e2b3;font-size:13px;font-weight:600}
.bv-band ul{list-style:none;margin:0 auto;display:flex;flex-wrap:wrap;gap:4px 18px;padding-top:7px;padding-bottom:7px}
.bv-band li::before{content:"◆";color:var(--brass2);margin-right:7px;font-size:9px;vertical-align:1px}
.bv-layout{display:grid;gap:18px;padding-top:20px;padding-bottom:40px;grid-template-columns:minmax(0,1fr)}
.bv-side{order:-1;min-width:0}
.bv-hero{order:-2}
.bv-side__in{display:grid;gap:14px}
.bv-promo{display:flex;flex-direction:column;gap:6px;background:var(--ink);color:#fff;border-radius:var(--r);padding:14px 16px;
border:1px dashed var(--brass2)}
.bv-promo__lab{font-size:12px;letter-spacing:.08em;text-transform:uppercase;color:#cdd3ea}
.bv-promo__row{display:flex;align-items:center;gap:10px}
.bv-promo__val{font:800 1.1rem/1 ui-monospace,Consolas,monospace;letter-spacing:.08em;background:#fff;color:var(--ink);
padding:9px 12px;border-radius:8px;border:2px solid var(--brass2)}
.bv-promo__btn{background:var(--mint);color:#fff;border:0;border-radius:8px;padding:10px 14px;font-weight:700;cursor:pointer}
.bv-promo__btn.bv-ok{background:#0d7d5d}
.bv-promo__hint{font-size:12.5px;color:#cdd3ea}
.bv-calc{background:var(--card);border:1px solid var(--line);border-radius:var(--r);overflow:hidden}
.bv-calc__sum{cursor:pointer;font-weight:800;padding:13px 16px;background:var(--mintbg);color:#0a5a43;list-style:none}
.bv-calc__sum::-webkit-details-marker{display:none}
.bv-calc__sum::after{content:"▾";float:right}
.bv-calc[open] .bv-calc__sum::after{content:"▴"}
.bv-calc__body{padding:12px 16px 16px;display:grid;gap:10px}
.bv-calc__f{display:grid;gap:4px;font-size:13px;font-weight:700;color:var(--mut)}
.bv-foot__in{display:block}
.bv-calc__stage,.bv-calc__amt{display:block}
.bv-calc__f select,.bv-calc__f input{font:600 15px/1.3 inherit;padding:9px 10px;border:1px solid var(--line);border-radius:8px;
background:#fff;color:var(--tx);width:100%}
.bv-calc__out{margin:0;display:grid;gap:0;border-top:1px solid var(--line)}
.bv-calc__out div{display:flex;justify-content:space-between;gap:10px;padding:7px 0;border-bottom:1px dotted var(--line)}
.bv-calc__out dt{color:var(--mut);font-size:14px}
.bv-calc__out dd{margin:0;font-weight:800;font-variant-numeric:tabular-nums}
.bv-calc__msg{font-size:12.5px;color:#a0541a;min-height:1em}
.bv-toc{display:none}
.bv-layout{counter-reset:bvs}
.bv-main{display:contents}
.bv-hero{background:radial-gradient(circle at 92% 12%,rgba(242,193,78,.35),transparent 42%),
linear-gradient(135deg,var(--ink),#26305c);color:#fff;border-radius:18px;padding:26px 20px 24px;margin-bottom:22px;position:relative;overflow:hidden}
.bv-hero::after{content:"";position:absolute;right:-34px;bottom:-34px;width:130px;height:130px;border-radius:50%;
border:14px solid rgba(242,193,78,.25);box-shadow:0 0 0 14px rgba(242,193,78,.12)}
.bv-hero h1{margin:0 0 12px;font:800 1.65rem/1.2 ui-serif,Georgia,serif;position:relative;z-index:1}
.bv-lede{margin:0;color:#e5e9f7;font-size:1.02rem;position:relative;z-index:1;max-width:60ch}
.bv-sec{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:20px 18px 6px;margin:0 0 20px;
position:relative}
.bv-sec h2{counter-increment:bvs;margin:0 0 14px;font:800 1.28rem/1.3 ui-serif,Georgia,serif;color:var(--ink);
padding-left:46px;position:relative}
.bv-sec h2::before{content:counter(bvs,decimal-leading-zero);position:absolute;left:0;top:-1px;width:36px;height:36px;
border-radius:50%;background:var(--ink);color:var(--brass2);font:800 .8rem/36px system-ui,sans-serif;text-align:center}
.bv-faq h2::before{content:"?"}
.bv-sec p{margin:0 0 14px}
.bv-fig{margin:0 0 16px;border-radius:12px;overflow:hidden;border:1px solid var(--line)}
.bv-fig img{width:100%}
.bv-tbl{overflow-x:auto;margin:6px 0 18px;border:1px solid var(--line);border-radius:10px;background:#fff}
.bv-tbl table{border-collapse:collapse;width:100%;min-width:480px;font-size:14.5px}
.bv-tbl caption{caption-side:top;text-align:left;font-weight:800;padding:10px 12px;background:var(--mintbg);color:#0a5a43}
.bv-tbl th{background:var(--ink);color:#f3e2b3;text-align:left;padding:9px 12px;font-size:13px;letter-spacing:.03em}
.bv-tbl td{padding:9px 12px;border-top:1px solid #ece4d0;vertical-align:top}
.bv-tbl tbody tr:nth-child(even) td{background:#faf6ea}
.bv-list{margin:0 0 16px;padding:0;list-style:none;display:grid;gap:8px}
.bv-list li{position:relative;padding:10px 12px 10px 40px;background:#faf6ea;border-radius:10px;border:1px solid #ece4d0}
.bv-list--ul li::before{content:"✓";position:absolute;left:12px;top:9px;width:20px;height:20px;border-radius:50%;
background:var(--mint);color:#fff;font-size:12px;line-height:20px;text-align:center;font-weight:800}
.bv-list--ol{counter-reset:bvo}
.bv-list--ol li{counter-increment:bvo}
.bv-list--ol li::before{content:counter(bvo);position:absolute;left:10px;top:9px;width:22px;height:22px;border-radius:6px;
background:var(--ink);color:var(--brass2);font-size:13px;line-height:22px;text-align:center;font-weight:800}
.bv-ctarow{margin:2px 0 20px;text-align:center}
.bv-faq__item{border:1px solid var(--line);border-radius:10px;margin:0 0 10px;background:#fff;overflow:hidden}
.bv-faq__q{cursor:pointer;font-weight:700;padding:13px 40px 13px 14px;position:relative;list-style:none}
.bv-faq__q::-webkit-details-marker{display:none}
.bv-faq__q::after{content:"+";position:absolute;right:14px;top:9px;font-size:22px;color:var(--brass)}
.bv-faq__item[open] .bv-faq__q::after{content:"–"}
.bv-faq__a{padding:0 14px 14px;color:var(--mut)}
.bv-foot{background:var(--ink);color:#cdd3ea;padding:28px 0;font-size:14px}
.bv-foot__logo{width:140px;height:auto;margin-bottom:12px}
.bv-foot__txt{margin:0 0 8px}
.bv-age{display:inline-block;border:2px solid var(--brass2);color:var(--brass2);border-radius:50%;width:32px;height:32px;
line-height:28px;text-align:center;font-weight:800;margin-right:8px;font-size:12px}
.bv-top{position:fixed;right:14px;bottom:16px;width:44px;height:44px;border-radius:50%;border:0;background:var(--ink);
color:var(--brass2);font-size:20px;cursor:pointer;box-shadow:0 3px 10px rgba(0,0,0,.3);z-index:40}
.bv-top.bv-top--on{display:block}
.bv-nf{padding:40px 0;text-align:center}
@media (min-width:900px){
 .bv-burger{display:none}
 .bv-head__bar{flex-wrap:nowrap}
 .bv-nav,.bv-nav--open{display:block;flex:1 1 auto;width:auto;margin-left:auto;padding:0}
 .bv-nav ul{display:flex;gap:4px;justify-content:flex-end;margin:0}
 .bv-nav li a{border:0;padding:8px 12px;border-radius:999px;font-size:14px}
 .bv-nav li a:hover{background:#26305c}
 .bv-nav__cta{display:none}
 .bv-head__cta{display:inline-block;padding:9px 20px}
 .bv-hero{padding:38px 36px 34px}
 .bv-hero h1{font-size:2.2rem}
 .bv-layout{grid-template-columns:minmax(0,1fr) 330px;gap:28px;padding-top:28px}
 .bv-side{order:0;grid-column:2;grid-row:1}
 .bv-main{display:block;min-width:0;grid-column:1;grid-row:1}
 .bv-hero{order:0}
 .bv-side__in{position:sticky;top:84px;max-height:calc(100vh - 100px);overflow:auto}
 .bv-toc{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:12px 16px}
 .bv-toc__t{font-weight:800;font-size:13px;text-transform:uppercase;letter-spacing:.07em;color:var(--mut)}
 .bv-toc ol{margin:8px 0 0;padding-left:18px;font-size:13.5px;line-height:1.45}
 .bv-toc li{margin-bottom:5px}
 .bv-toc a{color:var(--tx);text-decoration:none}
 .bv-toc a.bv-cur{color:#0b6b52;font-weight:800}
 .bv-sec{padding:26px 28px 10px}
}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}