:root {
  --bg: #f1f3ef;
  --paper: #fbfcfa;
  --side: #0f1a16;
  --side-ink: #dfe8e3;
  --side-muted: #8fa198;
  --ink: #0f1a16;
  --muted: #55625c;
  --line: #cfd6d0;
  --accent: #0b6e4f;
  --accent-ink: #fbfcfa;
  --accent-soft: #d6e9df;
  --signal: #6fe3b4;
  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Consolas, monospace;
  --side-w: 288px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b100e;
    --paper: #111916;
    --side: #070b0a;
    --ink: #e3ebe6;
    --muted: #93a39b;
    --line: #24302b;
    --accent: #4fc79b;
    --accent-ink: #0b100e;
    --accent-soft: #15302a;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; } }
body { margin: 0; background: var(--bg); color: var(--ink); font: 400 1rem/1.6 var(--sans); }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; background: var(--paper); padding: 8px 16px; z-index: 20; }
.mono { font-family: var(--mono); }
h1, h2, h3, h4 { overflow-wrap: break-word; hyphens: auto; }

/* ---------- sidebar ---------- */
.side {
  position: fixed; inset: 0 auto 0 0; width: var(--side-w); z-index: 10;
  background: var(--side); color: var(--side-ink);
  display: flex; flex-direction: column; padding: 28px 24px;
}
.logo { display: flex; align-items: center; gap: 10px; text-decoration: none; font: 600 1.25rem var(--mono); letter-spacing: -.02em; }
.logo-mark { width: 32px; height: 32px; border: 2px solid var(--signal); color: var(--signal); display: grid; place-items: center; font: 600 .8125rem var(--mono); }
.logo b { color: var(--signal); font-weight: 600; }
.side-tag { font: 400 .8125rem/1.5 var(--mono); color: var(--side-muted); margin: 16px 0 40px; }
.side-nav { display: grid; gap: 2px; font: 400 .9375rem var(--mono); }
.side-nav a { text-decoration: none; padding: 10px 12px; border-left: 2px solid transparent; color: var(--side-muted); min-height: 44px; display: flex; align-items: center; gap: 12px; }
.side-nav a span { color: var(--signal); font-size: .75rem; }
.side-nav a:hover, .side-nav a.on { color: var(--side-ink); border-left-color: var(--signal); background: rgba(255,255,255,.04); }
.side-bottom { margin-top: auto; display: grid; gap: 16px; }
.side-status { font: 400 .75rem/1.5 var(--mono); color: var(--side-muted); display: flex; gap: 8px; align-items: center; }
.side-status::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--signal); flex: none; }
.side .btn { background: var(--signal); color: #07120d; border-color: var(--signal); justify-content: center; }
.side .btn:hover { filter: brightness(1.08); background: var(--signal); color: #07120d; }
.menu-btn { display: none; }

.main { margin-left: var(--side-w); }
.in { max-width: 1040px; padding: 0 56px; }

@media (max-width: 1024px) {
  .side { position: sticky; top: 0; inset: auto; width: auto; flex-direction: row; align-items: center; flex-wrap: wrap; padding: 12px 16px; gap: 12px; }
  .side-tag, .side-status { display: none; }
  .side-nav { display: none; width: 100%; order: 3; padding: 8px 0; }
  .side.open .side-nav { display: grid; }
  .side-bottom { margin: 0 0 0 auto; display: flex; align-items: center; gap: 8px; }
  .side-bottom .btn { display: none; }
  .menu-btn {
    display: inline-flex; align-items: center; justify-content: center; min-width: 44px; min-height: 44px;
    background: transparent; border: 1px solid var(--side-muted); color: var(--side-ink); font: 400 .875rem var(--mono); cursor: pointer; padding: 0 12px;
  }
  .main { margin-left: 0; }
  .in { padding: 0 24px; }
}
@media (max-width: 600px) { .in { padding: 0 16px; } }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 10px; min-height: 48px; padding: 0 20px;
  border: 1px solid var(--ink); border-radius: 0; background: transparent; color: var(--ink);
  font: 500 .9375rem var(--sans); text-decoration: none; cursor: pointer;
}
.btn:hover { background: var(--paper); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn-primary:hover { background: var(--ink); border-color: var(--ink); color: var(--bg); }
.btn:disabled { opacity: .6; cursor: progress; }

/* ---------- hero ---------- */
.hero { padding: 96px 0 72px; border-bottom: 1px solid var(--line); }
.prompt { font: 400 .875rem var(--mono); color: var(--accent); margin: 0 0 28px; }
.prompt::after { content: "_"; animation: blink 1.1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }
@media (prefers-reduced-motion: reduce) { .prompt::after { animation: none; } }
.hero h1 { font: 600 clamp(2rem, 4.2vw, 3.375rem)/1.1 var(--sans); letter-spacing: -.025em; margin: 0 0 28px; max-width: 20ch; }
.hero .lead { font-size: 1.125rem; color: var(--muted); max-width: 60ch; margin: 0 0 36px; }
.actions { display: flex; gap: 12px; flex-wrap: wrap; }
.tags { list-style: none; margin: 56px 0 0; padding: 0; display: grid; grid-template-columns: repeat(5, 1fr); border-top: 1px solid var(--line); }
.tags li { padding: 16px 16px 0 0; font-size: .875rem; color: var(--muted); border-right: 1px solid var(--line); padding-right: 16px; margin-right: 16px; }
.tags li:last-child { border-right: 0; margin-right: 0; }
.tags li b { display: block; font: 500 .75rem var(--mono); color: var(--accent); margin-bottom: 8px; }
@media (max-width: 1200px) { .tags { grid-template-columns: repeat(3, 1fr); row-gap: 16px; } .tags li:nth-child(3) { border-right: 0; } }
@media (max-width: 640px) { .tags { grid-template-columns: 1fr; } .tags li { border-right: 0; margin-right: 0; border-bottom: 1px solid var(--line); padding-bottom: 12px; } }
@media (max-width: 600px) { .hero { padding: 48px 0; } }

/* ---------- sections ---------- */
section { padding: 88px 0; border-bottom: 1px solid var(--line); }
@media (max-width: 600px) { section { padding: 56px 0; } }
.sec-no { font: 400 .8125rem var(--mono); color: var(--muted); margin: 0 0 12px; }
.sec-no b { color: var(--accent); font-weight: 500; }
h2 { font: 600 clamp(1.625rem, 3vw, 2.25rem)/1.2 var(--sans); letter-spacing: -.015em; margin: 0 0 20px; max-width: 30ch; }
.prose { color: var(--muted); max-width: 68ch; font-size: 1.0625rem; margin: 0 0 40px; }

.comp { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 12px; }
.comp li { background: var(--paper); border: 1px solid var(--line); padding: 20px; font-size: .9375rem; min-height: 120px; display: flex; flex-direction: column; justify-content: space-between; gap: 16px; }
.comp li::before { content: attr(data-k); font: 500 .75rem var(--mono); color: var(--accent); }

/* modules */
.module { margin-top: 48px; }
.module:first-of-type { margin-top: 0; }
.mod-head { display: flex; align-items: baseline; gap: 16px; padding: 14px 0; border-bottom: 2px solid var(--ink); }
.mod-head span { font: 500 .8125rem var(--mono); color: var(--accent); }
.mod-head h3 { font: 600 1.375rem/1.3 var(--sans); margin: 0; }
.rows { list-style: none; margin: 0; padding: 0; }
.rows li { display: grid; grid-template-columns: 260px 1fr; gap: 24px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.rows h4 { font: 600 1rem/1.4 var(--sans); margin: 0; }
.rows p { margin: 0; color: var(--muted); font-size: .9375rem; }
.rows .k { font: 400 .75rem var(--mono); color: var(--accent); display: block; margin-bottom: 4px; }
.result { display: flex; gap: 12px; padding: 14px 16px; background: var(--accent-soft); font-size: .9375rem; margin-top: 12px; }
.result b { font: 500 .75rem/1.9 var(--mono); color: var(--accent); text-transform: uppercase; white-space: nowrap; }
.cols { columns: 2; column-gap: 32px; list-style: none; margin: 0; padding: 12px 0 0; }
.cols li { break-inside: avoid; padding: 10px 0; border-bottom: 1px solid var(--line); font-size: .9375rem; }
.cols li::before { content: "$ "; font-family: var(--mono); color: var(--accent); }
@media (max-width: 760px) { .rows li { grid-template-columns: 1fr; gap: 4px; } .cols { columns: 1; } .result { flex-direction: column; gap: 2px; } }

/* cases */
.cases { display: grid; gap: 12px; }
.case { display: grid; grid-template-columns: 200px 1fr 1fr; gap: 24px; background: var(--paper); border: 1px solid var(--line); padding: 24px; }
.case h3 { font: 600 1.125rem/1.35 var(--sans); margin: 0; }
.case .mono { font-size: .75rem; color: var(--accent); display: block; margin-bottom: 8px; }
.case p { margin: 0; color: var(--muted); font-size: .9375rem; }
.case dl { margin: 0; display: grid; gap: 8px; font-size: .9375rem; }
.case dt { font: 400 .75rem var(--mono); color: var(--muted); }
.case dd { margin: 0; }
@media (max-width: 860px) { .case { grid-template-columns: 1fr; gap: 12px; } }

/* process */
.pipeline { list-style: none; margin: 0; padding: 0; counter-reset: p; display: grid; grid-template-columns: repeat(7, 1fr); gap: 0; }
.pipeline li { counter-increment: p; padding: 0 12px 0 0; position: relative; }
.pipeline li::before { content: counter(p); display: grid; place-items: center; width: 36px; height: 36px; border: 1px solid var(--ink); background: var(--bg); font: 500 .8125rem var(--mono); position: relative; z-index: 1; margin-bottom: 16px; }
.pipeline li::after { content: ""; position: absolute; top: 18px; left: 36px; right: 0; height: 1px; background: var(--line); }
.pipeline li:last-child::after { display: none; }
.pipeline h3 { font: 600 .9375rem/1.35 var(--sans); margin: 0 0 6px; }
.pipeline p { margin: 0; color: var(--muted); font-size: .8125rem; line-height: 1.5; }
@media (max-width: 1200px) {
  .pipeline { grid-template-columns: 1fr; gap: 0; border-left: 1px solid var(--line); margin-left: 18px; }
  .pipeline li { padding: 0 0 24px 32px; }
  .pipeline li::before { position: absolute; left: -18px; top: -4px; margin: 0; }
  .pipeline li::after { display: none; }
}

/* contact + requisites */
.contact { display: grid; grid-template-columns: 1.1fr 1fr; gap: 40px; align-items: start; }
form { display: grid; gap: 16px; background: var(--paper); border: 1px solid var(--line); padding: 28px; }
label { display: grid; gap: 6px; font: 400 .8125rem var(--mono); color: var(--muted); }
input, textarea { font: 400 1rem var(--sans); color: var(--ink); background: var(--bg); border: 1px solid var(--line); border-radius: 0; padding: 12px 14px; min-height: 48px; width: 100%; }
textarea { min-height: 110px; resize: vertical; }
input:focus, textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.check { display: flex; gap: 12px; align-items: flex-start; font: 400 .875rem var(--sans); }
.check input { width: 20px; height: 20px; min-height: 0; margin-top: 2px; accent-color: var(--accent); flex: none; }
.opt { opacity: .75; }
.form-note { font-size: .875rem; color: var(--muted); min-height: 1.4em; margin: 0; }
.form-note.err { color: #b3261e; }
@media (prefers-color-scheme: dark) { .form-note.err { color: #f2b8b5; } }
.req-box { border: 1px solid var(--line); background: var(--paper); }
.req-box h3 { font: 500 .8125rem var(--mono); color: var(--muted); margin: 0; padding: 14px 20px; border-bottom: 1px solid var(--line); }
.req { margin: 0; }
.req div { display: grid; grid-template-columns: 120px 1fr; gap: 12px; padding: 12px 20px; border-bottom: 1px solid var(--line); font-size: .875rem; }
.req div:last-child { border-bottom: 0; }
.req dt { font: 400 .75rem/1.9 var(--mono); color: var(--muted); }
.req dd { margin: 0; overflow-wrap: anywhere; }
@media (max-width: 1100px) { .contact { grid-template-columns: 1fr; } }
@media (max-width: 480px) { .req div { grid-template-columns: 1fr; gap: 2px; } form { padding: 20px; } }

.foot { padding: 24px 0 40px; font: 400 .75rem var(--mono); color: var(--muted); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; }

.doc { max-width: 760px; padding: 64px 0 96px; }
.doc h1 { font: 600 clamp(1.75rem, 4vw, 2.5rem)/1.2 var(--sans); margin: 0 0 32px; }
.doc h2 { font-size: 1.25rem; margin: 40px 0 12px; }
.doc p { color: var(--muted); }
.side .back { display: inline-flex !important; }