:root{
  --bg:#f6f8fb; --surface:#fff; --ink:#111827; --muted:#5b6b80;
  --accent:#2563eb; --accent-2:#1d4ed8; --soft:#eef4ff; --line:#e5eaf2;
  --radius:18px; --shadow:0 1px 2px rgba(17,24,39,.04), 0 18px 40px -28px rgba(17,24,39,.35);
  --wrap:1120px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);
  font:17px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  -webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 20px}
h1,h2,h3{letter-spacing:-.02em;line-height:1.2;font-weight:500;margin:0}
h1{font-size:clamp(30px,4vw,44px)}
h2{font-size:clamp(22px,2.4vw,28px);margin:0 0 14px}
h3{font-size:19px;margin:26px 0 10px;color:#0f172a}
p{margin:0 0 14px}
ul,ol{margin:0 0 16px;padding-left:22px}
li{margin:6px 0}
.muted{color:var(--muted)}

/* шапка */
.hdr{position:sticky;top:0;z-index:40;background:rgba(255,255,255,.88);
  backdrop-filter:saturate(180%) blur(12px);border-bottom:1px solid var(--line)}
.hdr__in{display:flex;align-items:center;gap:24px;height:66px}
.brand{display:flex;align-items:center;gap:10px;font-weight:600;color:var(--ink);font-size:16px}
.brand:hover{text-decoration:none}
.brand__mark{width:34px;height:34px;border-radius:10px;flex:none;display:grid;place-items:center;
  background:linear-gradient(140deg,#3b82f6,#1d4ed8);color:#fff;font-size:14px;font-weight:600}
.nav{display:flex;gap:22px;margin-left:auto;font-size:15px}
.nav a{color:#334155}
.nav a:hover{color:var(--accent);text-decoration:none}
@media(max-width:820px){.nav{display:none}}

/* герой — калькулятор занимает первый экран */
.hero{min-height:calc(100dvh - 66px);display:flex;flex-direction:column;justify-content:center;
  padding:12px 0 20px}
.hero__in{width:100%}
.hero__head{text-align:center;margin:0 auto 14px;max-width:820px}
.hero h1{font-size:clamp(24px,2.9vw,34px);margin-bottom:6px}
.hero__lead{color:var(--muted);margin:0;font-size:15.5px}
@media(max-width:720px){
  .hero{min-height:0;padding-top:16px;padding-bottom:8px}
  .hero__head{text-align:left;margin-bottom:10px}
  .hero__lead{display:none}
  .hero h1{margin-bottom:0}
}

/* калькулятор */
.calc{width:100%;max-width:1060px;margin:0 auto;background:var(--surface);
  border:1px solid var(--line);border-radius:22px;padding:20px 22px;min-width:0;
  box-shadow:0 1px 2px rgba(17,24,39,.04),0 34px 64px -44px rgba(17,24,39,.5)}
.calc__label{display:block;font-size:12px;letter-spacing:.1em;text-transform:uppercase;
  color:var(--muted);margin-bottom:7px}
.calc__row{display:flex;gap:10px;align-items:stretch;min-width:0}
.main_chislo{flex:1 1 0;width:100%;min-width:0;font:inherit;font-weight:500;
  font-size:clamp(24px,3.2vw,34px);line-height:1.2;padding:9px 16px;
  border:1.5px solid var(--line);border-radius:14px;background:#fff;color:var(--ink);
  font-variant-numeric:tabular-nums}
.main_chislo:focus{outline:none;border-color:#b9cdf0;box-shadow:0 0 0 4px rgba(37,99,235,.1)}
.main_chislo_sbmt{flex:0 0 auto;border:0;border-radius:14px;background:var(--accent);color:#fff;
  font:inherit;font-size:15px;font-weight:500;padding:0 22px;cursor:pointer;white-space:nowrap}
.main_chislo_sbmt:hover{background:var(--accent-2)}
.main_chislo_slovami{font-size:13.5px;color:var(--muted);margin-top:8px;min-height:18px}
.calc__opts{display:flex;flex-wrap:wrap;gap:12px 26px;justify-content:space-between;margin-top:12px}
@media(max-width:820px){.calc__opts{flex-direction:column;gap:10px}}
.radio-group{margin:0}
.radio-group__title{font-size:12.5px;color:var(--muted);margin-bottom:7px}
.chips{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:6px}
.chips li{margin:0}
.chips label{display:inline-flex;align-items:center;cursor:pointer}
.chips input{position:absolute;opacity:0;pointer-events:none}
.chips span{display:inline-block;padding:8px 13px;border:1px solid var(--line);border-radius:999px;
  font-size:14.5px;color:#334155;background:#fff;transition:.15s}
.chips input:checked+span{background:var(--soft);border-color:#bfd3f5;color:var(--accent)}
.chips input:focus-visible+span{box-shadow:0 0 0 3px rgba(37,99,235,.18)}

.results{margin-top:14px;border-top:1px solid var(--line);padding-top:12px}
.results_tabs_captions ul{list-style:none;padding:5px;margin:0 0 14px;display:grid;
  grid-template-columns:repeat(3,1fr);gap:5px;background:#eef2f9;border-radius:14px}
.results_tab{padding:13px 8px;border-radius:10px;font-size:16px;color:#3b4757;cursor:pointer;
  text-align:center;line-height:1.25;transition:.15s}
.results_tab:hover{background:#fff;color:var(--accent)}
.results_tab_active{background:var(--accent);color:#fff;
  box-shadow:0 8px 18px -10px rgba(37,99,235,.9)}
.results_tab_active:hover{background:var(--accent-2);color:#fff}
.results_blocks{display:block}
.no_show{display:none}
.shab_view{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.res-item{display:flex;flex-direction:column;gap:2px;padding:11px 13px;min-width:0;
  border:1px solid var(--line);border-radius:14px;background:#f9fbff}
.res-label{font-size:12.5px;color:var(--muted)}
.res-value{font-size:clamp(19px,2.2vw,25px);font-weight:500;font-variant-numeric:tabular-nums;
  cursor:copy;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.res-value:hover{color:var(--accent)}
.res-words{font-size:11.5px;color:#7b8aa0;line-height:1.35;cursor:copy}
.calc__hints{margin-top:10px;font-size:12.5px;color:#8a97a8}

/* контентные блоки */
.sec-lead{color:var(--muted);font-size:15.5px;margin:-4px 0 16px}
.card .sec-lead{margin-bottom:18px}
.lead{font-size:18.5px;line-height:1.62;color:#1f2937;margin:0 0 18px}
.summary{background:#f2f7ff;border:1px solid #dbe8fd;border-radius:16px;padding:16px 20px;margin:0 0 24px}
.summary__title{font-size:12px;letter-spacing:.09em;text-transform:uppercase;color:var(--accent);margin-bottom:8px}
.summary ul{margin:0;padding-left:20px}
.summary li{margin:5px 0;color:#26313f}
.callout{background:#f7faff;border:1px solid #e2ecfa;border-left:3px solid var(--accent);
  border-radius:12px;padding:13px 16px;margin:18px 0;font-size:15.5px;color:#26313f;line-height:1.6}
.callout__title{font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--accent);margin-bottom:5px}
.fig{margin:24px 0}
.fig img{display:block;width:100%;height:auto;border-radius:16px;border:1px solid var(--line);background:#f7faff}
.fig figcaption{font-size:13px;color:var(--muted);margin-top:8px;text-align:center;line-height:1.45}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:12px;margin:16px 0}
.mini{background:#fbfcff;border:1px solid var(--line);border-radius:14px;padding:14px 16px}
.mini__ic{width:30px;height:30px;border-radius:9px;background:#eef4ff;color:var(--accent);
  display:grid;place-items:center;margin-bottom:9px}
.mini__t{font-size:15.5px;color:#0f172a;margin-bottom:5px}
.mini p{margin:0;font-size:14.5px;color:#4b5869;line-height:1.55}
.formula-card{background:#f9fbff;border:1px solid var(--line);border-radius:14px;padding:12px 16px;margin:14px 0}
.formula-row{display:flex;gap:14px;justify-content:space-between;align-items:baseline;padding:7px 0;
  border-bottom:1px dashed #e7edf7;font-size:15.5px;color:#3b4757}
.formula-row:last-child{border-bottom:0}
.example{background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 16px;margin:14px 0}
.example__head{font-size:13.5px;color:var(--muted);margin-bottom:8px}
.example__row{display:flex;gap:16px;justify-content:space-between;align-items:baseline;
  padding:7px 0;border-bottom:1px dashed #eef2f9;font-size:15px;color:#4b5869}
.example__row:last-child{border-bottom:0}
.example__sum{font-variant-numeric:tabular-nums;color:#0f172a;white-space:nowrap}
.example__sum--accent{color:var(--accent)}
.checks{list-style:none;padding:0;margin:16px 0}
.checks li{display:flex;gap:10px;align-items:flex-start;margin:10px 0;color:#26313f;font-size:15.5px}
.checks__ic{flex:none;width:24px;height:24px;border-radius:50%;background:#eef4ff;color:var(--accent);
  display:grid;place-items:center;margin-top:1px}
.li-t{color:#0f172a}
.cta{display:inline-flex;align-items:center;gap:8px;background:var(--accent);color:#fff;
  padding:12px 22px;border-radius:12px;margin:6px 0 10px;font-size:15.5px}
.cta:hover{background:var(--accent-2);text-decoration:none}
.cta::after{content:"→"}
.card table{width:100%;border-collapse:collapse;margin:6px 0 4px;font-size:15.5px}
.card th,.card td{border-bottom:1px solid var(--line);padding:10px 12px 10px 0;text-align:left;
  vertical-align:top;color:#26313f}
.card td:first-child{width:26%;min-width:150px;color:var(--muted);padding-right:24px}
.card tr:last-child td{border-bottom:0}
table.rates{width:100%;border-collapse:collapse;margin:10px 0 18px;font-size:15.5px}
table.rates th{font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);
  border-bottom:1px solid var(--line);padding:8px 12px 8px 0;text-align:left}
table.rates td{border-bottom:1px solid var(--line);padding:10px 12px 10px 0;vertical-align:top}
table.rates td:first-child,table.rates th:first-child{width:96px}
.meta-line{font-size:13.5px;color:var(--muted);margin:-8px 0 20px}
.chain{background:#f9fbff;border:1px solid var(--line);border-radius:16px;padding:14px 16px;margin:18px 0}
.chain__title{font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--accent);margin-bottom:8px}
.chain__row{display:flex;gap:14px;justify-content:space-between;align-items:baseline;
  padding:8px 0;border-bottom:1px dashed #e7edf7;font-size:15px;color:#4b5869}
.chain__row:last-child{border-bottom:0}
.chain__row--total{color:#0f172a;font-size:15.5px}
.chain__sum{font-variant-numeric:tabular-nums;white-space:nowrap;color:#0f172a}
.chain__row--total .chain__sum{color:var(--accent)}
.errors{counter-reset:e;list-style:none;padding:0;margin:18px 0}
.errors li{counter-increment:e;position:relative;padding-left:40px;margin:14px 0;color:#26313f;
  font-size:15.5px;line-height:1.6}
.errors li::before{content:counter(e);position:absolute;left:0;top:1px;width:27px;height:27px;
  border-radius:50%;background:#eef4ff;color:var(--accent);display:grid;place-items:center;font-size:13px}
.errors__t{display:block;color:#0f172a;margin-bottom:2px}
.disclaimer{font-size:13px;color:var(--muted);border-top:1px solid var(--line);
  padding-top:14px;margin-top:24px}
table.rates td:nth-child(3){color:var(--muted);font-variant-numeric:tabular-nums}
table.rates tr.rates__main td{color:#0f172a}
table.rates tr.rates__main td:first-child{color:var(--accent)}
@media(max-width:720px){
  .cards{grid-template-columns:1fr}
  .chain__row{flex-direction:column;gap:2px;align-items:flex-start}
  .chain__sum{white-space:normal}
  .errors li{padding-left:34px}
  table.rates{display:block}
  .example__row{flex-direction:column;gap:2px;align-items:flex-start}
  .formula-row{flex-direction:column;gap:4px;align-items:flex-start}
  .lead{font-size:17px}
}


@media(max-width:720px){
  .calc{padding:14px 12px;border-radius:18px}
  .calc__hints{display:none}
  .main_chislo_sbmt{display:none}
  .chips{gap:5px}
  .chips span{padding:6px 8px;font-size:12.8px}
  .results{margin-top:10px;padding-top:10px}
  .results_tabs_captions ul{margin-bottom:8px}
  .results_tab{padding:12px 4px;font-size:13.5px}
  .shab_view{grid-template-columns:1fr;gap:6px}
  .res-item{flex-direction:row;align-items:center;justify-content:space-between;
    flex-wrap:wrap;padding:8px 12px}
  .res-label{flex:1 1 auto;font-size:13px}
  .res-value{flex:0 0 auto;font-size:19px}
  .res-words{display:none}
  .res-item:last-child .res-words{display:block;flex:1 0 100%;font-size:11px;margin-top:2px}
}
.copy_info{display:none;font-size:12.5px;color:var(--muted);margin-top:8px}
.copy_info_cit{color:var(--accent)}
.note{font-size:13.5px;color:var(--muted);margin-top:14px}

/* секции контента */
.section{padding-top:40px;padding-bottom:0}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 28px;box-shadow:var(--shadow)}
.article{max-width:820px;margin:0 auto;background:var(--surface);border:1px solid var(--line);
  border-radius:var(--radius);padding:34px 36px;box-shadow:var(--shadow)}
@media(max-width:640px){
  .article{padding:22px 18px;border-radius:14px}
  .card{padding:20px 18px}
  .article table{font-size:14px}
  .article th,.article td{padding:8px 6px}
  ul,ol{padding-left:18px}
}
.article h2{margin-top:32px}
.article h2:first-child{margin-top:0}
.article h3{margin-top:30px;font-size:20px;color:#0f172a}
.article p{color:#26313f}
.article ul li,.article ol li{color:#26313f}
.article table{width:100%;border-collapse:collapse;margin:14px 0 20px;font-size:15.5px;
  table-layout:fixed;word-wrap:break-word;overflow-wrap:anywhere}
.article th,.article td{border-bottom:1px solid var(--line);padding:10px 8px;text-align:left;
  vertical-align:top}
.article th{color:var(--muted);font-weight:400;font-size:13px;text-transform:uppercase;letter-spacing:.06em}
.article td:first-child,.article th:first-child{width:30%}
@media(max-width:640px){.article td:first-child,.article th:first-child{width:38%}}

/* оглавление */
.toc{background:#f9fbff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;margin:0 0 24px}
.toc__title{font-size:13px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin-bottom:10px}
.toc ol{margin:0;padding-left:20px;columns:2;column-gap:28px;font-size:14.5px}
@media(max-width:720px){.toc ol{columns:1}}
.toc a{color:#334155}
.toc a:hover{color:var(--accent);text-decoration:none}

/* FAQ */
details{border-bottom:1px solid var(--line);padding:12px 0}
details:last-of-type{border-bottom:0}
summary{cursor:pointer;font-size:16px;color:#1f2937;list-style:none}
summary::-webkit-details-marker{display:none}
summary::before{content:"+";color:var(--accent);display:inline-block;width:18px}
details[open] summary::before{content:"–"}
details p{margin:10px 0 0 18px;color:#3b4757}
.faq-lead{color:var(--muted);font-size:15px}

/* формулы */
.formula{background:#f9fbff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;
  font-size:16px;margin:12px 0 18px;font-variant-numeric:tabular-nums;color:#1f2937}
.f{background:#f3f7fd;border:1px solid #e2ebf7;border-radius:8px;padding:2px 7px;
  font-size:14.5px;color:#1d3f7a;white-space:nowrap;display:inline-block;margin:2px 0}
.card h3{font-size:20px;margin:28px 0 10px;color:#0f172a;letter-spacing:-.01em;line-height:1.4}

/* подвал */
.ftr{border-top:1px solid var(--line);margin-top:40px;padding:26px 0 40px;color:var(--muted);
  font-size:13.5px}
.ftr__in{display:flex;gap:16px;justify-content:space-between;flex-wrap:wrap;align-items:center}
.top{position:fixed;right:18px;bottom:18px;width:42px;height:42px;border-radius:50%;
  background:#fff;border:1px solid var(--line);display:grid;place-items:center;color:var(--accent);
  box-shadow:var(--shadow);text-decoration:none;font-size:16px}
@media(max-width:720px){
  .f{white-space:normal;overflow-wrap:anywhere;word-break:break-word;display:inline}

  /* таблицы на телефоне — карточками, иначе слова рвутся по буквам */
  table.rates{display:block;border:0}
  table.rates thead{display:none}
  table.rates tbody{display:block}
  table.rates tr{display:block;border:1px solid var(--line);border-radius:12px;
    padding:10px 12px;margin:0 0 10px;background:#fbfcff}
  table.rates td{display:block;border:0;padding:2px 0;width:auto;font-size:14.5px;
    overflow-wrap:normal;word-break:normal}
  table.rates td:first-child{font-size:17px;color:var(--accent);padding-bottom:4px}
  table.rates td:nth-child(3){color:var(--muted);font-size:13.5px}

  .card table{display:block}
  .card tbody{display:block}
  .card tr{display:block;border-bottom:1px solid var(--line);padding:10px 0}
  .card tr:last-child{border-bottom:0}
  .card td{display:block;border:0;padding:1px 0;width:auto;min-width:0;
    overflow-wrap:normal;word-break:normal}
  .card td:first-child{width:auto;color:#0f172a;padding-right:0}
}
@media(max-width:640px){.top{display:none}}