:root{--bg:#eef1f4;--surface:#fbfcfd;--ink:#1b2530;--muted:#4a5866;--line:#cfd6de;--steel:#2f5d86;--steel-deep:#234867;--tint:#e1e8ef;--foot:#dce3ea}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:16px}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 "Helvetica Neue",Helvetica,"Nimbus Sans","Liberation Sans",Arial,sans-serif;padding-bottom:84px}
a{color:var(--steel)}a:hover{color:var(--steel-deep)}
svg{max-width:100%;height:auto}

.site-header{background:var(--surface);border-bottom:1px solid var(--line)}
.site-header__inner{max-width:1180px;margin:0 auto;padding:6px 16px;display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:60px}
.brand{display:flex;align-items:center;gap:10px;color:var(--ink);text-decoration:none;min-height:44px}
.brand__name{display:block;font-weight:700;font-size:18px;letter-spacing:-.02em;line-height:1.1}
.brand__tag{display:block;font-size:13px;color:var(--muted);line-height:1.2}
.site-nav{position:relative}
.site-nav__toggle{list-style:none;cursor:pointer;min-height:44px;display:flex;align-items:center;gap:8px;padding:0 14px;border:1px solid var(--line);border-radius:3px;font-size:15px;background:var(--surface)}
.site-nav__toggle::-webkit-details-marker{display:none}
.site-nav__list{list-style:none;margin:0;padding:6px 0;position:absolute;right:0;top:calc(100% + 6px);width:min(300px,calc(100vw - 32px));background:var(--surface);border:1px solid var(--line);border-radius:3px;z-index:30;box-shadow:0 8px 20px rgba(27,37,48,.14)}
.site-nav__link{display:flex;align-items:center;min-height:44px;padding:0 16px;color:var(--ink);text-decoration:none;line-height:1.3}
.site-nav__link:hover{background:var(--tint);color:var(--ink)}
.site-nav__link--current{font-weight:700;color:var(--steel)}
.site-bar{display:none}
.site-bar__link{display:flex;align-items:center;min-height:44px;padding:0 12px;color:var(--ink);text-decoration:none;font-size:15px;border-radius:3px}
.site-bar__link:hover{background:var(--tint);color:var(--ink)}
.site-bar__link--current{color:var(--steel);font-weight:700}

.layout{max-width:1180px;margin:0 auto;padding:12px 16px 48px;display:grid;gap:24px}
.layout__intro,.layout__main{min-width:0;max-width:780px}
.crumbs__list{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;font-size:14px;color:var(--muted)}
.crumbs__item{display:flex;align-items:center}
.crumbs__item+.crumbs__item::before{content:"/";margin:0 8px;color:var(--muted)}
.crumbs__link{display:inline-flex;align-items:center;min-height:44px;color:var(--steel)}
.headline{font-size:28px;line-height:1.18;letter-spacing:-.02em;margin:8px 0 6px}
.updated{font-size:14px;color:var(--muted);margin:0 0 16px}
.answer{background:var(--surface);border:1px solid var(--line);border-radius:3px;padding:14px 16px;margin:0 0 16px}
.answer__label{display:block;font-size:13px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin-bottom:4px}
.answer__text{margin:0;font-size:17px}
.cta-btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:48px;padding:0 22px;background:var(--steel);border:1px solid var(--steel-deep);border-radius:3px;color:var(--surface);font-weight:700;font-size:16px;text-decoration:none}
.cta-btn:hover{background:var(--steel-deep);color:var(--surface)}
.cta-btn--block{display:flex;width:100%}
.cta-note{font-size:14px;color:var(--muted);margin:8px 0 0}

.toc{background:var(--surface);border:1px solid var(--line);border-radius:3px;padding:12px 0 6px}
.toc__title{font-size:13px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin:0 16px 4px}
.toc__list{list-style:none;margin:0;padding:0;counter-reset:toc}
.toc__link{display:flex;align-items:center;gap:10px;min-height:44px;padding:4px 16px;color:var(--ink);text-decoration:none;font-size:15px;line-height:1.35}
.toc__link::before{counter-increment:toc;content:counter(toc) ".";color:var(--steel);font-weight:700;min-width:1.4em}
.toc__link:hover{background:var(--tint);color:var(--ink)}

.section{margin-top:40px}
.section:first-child{margin-top:0}
.section__title{font-size:22px;line-height:1.25;letter-spacing:-.01em;margin:0 0 12px;padding-bottom:8px;border-bottom:1px solid var(--line)}
.section__sub{font-size:18px;line-height:1.3;margin:24px 0 8px}
.section__text{margin:0 0 12px}
.section__list{margin:0 0 12px;padding-left:22px}
.section__list li{margin-bottom:6px}

.data-table{width:100%;border-collapse:collapse;background:var(--surface);border:1px solid var(--line)}
.data-table__cell{text-align:left;vertical-align:top;padding:10px 8px;border-bottom:1px solid var(--line)}
.data-table__cell--head{background:var(--tint);font-size:14px;line-height:1.3}
.data-table__cell--key{font-weight:700}
.data-table__cell--num{white-space:nowrap}
.data-table__caption{caption-side:bottom;text-align:left;font-size:14px;color:var(--muted);padding-top:8px}
.speed{display:inline-flex;align-items:center;gap:6px}
.speed__bars{display:inline-flex;gap:2px;align-items:flex-end}
.speed__bar{width:4px;background:var(--line);border-radius:1px}
.speed__bar:nth-child(1){height:6px}.speed__bar:nth-child(2){height:10px}.speed__bar:nth-child(3){height:14px}
.speed__bar--on{background:var(--steel)}

.scheme{margin:16px 0;padding:16px;background:var(--surface);border:1px solid var(--line);border-radius:3px}
.scheme__img{display:block;margin:0 auto;width:100%;max-width:340px}
.scheme__caption{font-size:14px;color:var(--muted);margin-top:8px}

.steps{list-style:none;margin:0;padding:0;counter-reset:step}
.step{display:grid;gap:12px;padding:20px 0;border-bottom:1px solid var(--line)}
.step__head{display:flex;gap:12px;align-items:baseline}
.step__num{flex:none;display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border:1px solid var(--steel);border-radius:3px;color:var(--steel);font-weight:700}
.step__title{font-size:18px;line-height:1.3;margin:0}
.step__text{margin:0}
.step__figure{margin:0;display:flex;justify-content:center;padding:12px;background:var(--tint);border-radius:3px}

.checklist{list-style:none;margin:0 0 12px;padding:0;border:1px solid var(--line);border-radius:3px;background:var(--surface)}
.checklist__item{display:grid;grid-template-columns:20px minmax(0,1fr);gap:10px;padding:12px 14px;border-bottom:1px solid var(--line)}
.checklist__item:last-child{border-bottom:0}
.checklist__mark{width:16px;height:16px;margin-top:4px;border:2px solid var(--steel);border-radius:2px}

.faq__item{border-bottom:1px solid var(--line)}
.faq__item:first-child{border-top:1px solid var(--line)}
.faq__q{list-style:none;cursor:pointer;display:flex;justify-content:space-between;align-items:center;gap:16px;min-height:52px;padding:8px 0;font-weight:700;line-height:1.35}
.faq__q::-webkit-details-marker{display:none}
.faq__q::after{content:"+";flex:none;width:28px;height:28px;display:inline-flex;align-items:center;justify-content:center;border:1px solid var(--line);border-radius:3px;color:var(--steel);font-weight:400;font-size:20px}
.faq__item[open] .faq__q::after{content:"−"}
.faq__a{margin:0 0 14px;color:var(--ink)}

.closing{margin-top:48px;padding:24px 20px;background:var(--tint);border:1px solid var(--line);border-radius:3px}
.closing__title{font-size:22px;line-height:1.25;margin:0 0 8px}
.closing__text{margin:0 0 16px}

.sticky-cta{position:fixed;left:0;right:0;bottom:0;z-index:40;display:flex;align-items:center;gap:12px;padding:10px 16px calc(10px + env(safe-area-inset-bottom));background:var(--surface);border-top:1px solid var(--line);box-shadow:0 -4px 14px rgba(27,37,48,.08)}
.sticky-cta__text{flex:1;font-size:14px;line-height:1.3;color:var(--muted)}
.sticky-cta__text b{display:block;color:var(--ink);font-size:15px}

.page-footer{background:var(--foot);border-top:1px solid var(--line);font-size:14px;color:var(--muted)}
.page-footer__inner{max-width:1180px;margin:0 auto;padding:28px 16px;display:grid;gap:24px}
.page-footer__heading{font-size:13px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--ink);margin:0 0 4px}
.page-footer__links{list-style:none;margin:0;padding:0}
.page-footer__link{display:flex;align-items:center;min-height:44px;color:var(--ink)}
.page-footer__legal{margin:0;line-height:1.5}

@media (min-width:960px){
  body{padding-bottom:0}
  .site-nav{display:none}
  .site-bar{display:flex;gap:2px;list-style:none;margin:0;padding:0}
  .layout{grid-template-columns:250px minmax(0,1fr);grid-template-areas:"aside intro" "aside main";column-gap:48px;row-gap:32px;padding-top:28px}
  .layout__intro{grid-area:intro}.layout__aside{grid-area:aside}.layout__main{grid-area:main}
  .toc{position:sticky;top:24px}
  .headline{font-size:38px}
  .step{grid-template-columns:minmax(0,1fr) 190px;align-items:start}
  .step__figure{grid-row:1/3;grid-column:2}
  .sticky-cta{display:none}
  .page-footer__inner{grid-template-columns:1fr 1fr 2fr}
}