:root {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --panel-2: #f0f3f8;
  --text: #172033;
  --muted: #647089;
  --line: #dfe5ef;
  --accent: #3157d5;
  --accent-2: #2445b2;
  --good: #1f8a5b;
  --warn: #b7791f;
  --bad: #c2414c;
  --info: #2774a8;
  --shadow: 0 12px 34px rgba(28, 42, 68, .08);
  --radius: 18px;
  --sidebar: 286px;
  --content-max: 1040px;
}

[data-theme="dark"] {
  --bg: #0f1420;
  --panel: #171d2a;
  --panel-2: #202838;
  --text: #edf1f7;
  --muted: #a7b0c2;
  --line: #30394b;
  --accent: #8da4ff;
  --accent-2: #b8c5ff;
  --good: #66d6a4;
  --warn: #f0bd5f;
  --bad: #ff8790;
  --info: #76bce9;
  --shadow: 0 12px 34px rgba(0, 0, 0, .22);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.62;
}
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: var(--accent); }
code, pre { font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; }

.app-shell { min-height: 100vh; }
.sidebar {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--sidebar);
  background: var(--panel);
  border-right: 1px solid var(--line);
  padding: 22px 16px;
  overflow-y: auto;
  z-index: 20;
}
.main-shell { margin-left: var(--sidebar); min-height: 100vh; }
.topbar {
  position: sticky;
  top: 0;
  z-index: 15;
  min-height: 72px;
  background: color-mix(in srgb, var(--panel) 92%, transparent);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 12px 28px;
}
.content { max-width: var(--content-max); margin: 0 auto; padding: 34px 34px 90px; outline: none; }

.brand { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
.brand-mark {
  width: 42px; height: 42px; border-radius: 14px;
  display: grid; place-items: center; background: var(--accent); color: white;
  font-weight: 800; letter-spacing: -.04em;
}
.brand-copy strong { display: block; font-size: 15px; }
.brand-copy span { color: var(--muted); font-size: 12px; }

.nav-group { margin: 18px 0; }
.nav-label { text-transform: uppercase; letter-spacing: .09em; font-size: 11px; color: var(--muted); margin: 8px 10px; font-weight: 700; }
.nav-link {
  display: flex; align-items: center; gap: 10px; width: 100%;
  color: var(--text); text-decoration: none; padding: 9px 10px; border-radius: 11px;
  font-size: 14px; margin: 2px 0;
}
.nav-link:hover, .nav-link.active { background: var(--panel-2); }
.nav-link .nav-icon { width: 22px; text-align: center; }
.nav-link .nav-meta { margin-left: auto; color: var(--muted); font-size: 11px; }

.progress-rail { height: 7px; background: var(--panel-2); border-radius: 999px; overflow: hidden; }
.progress-rail > span { display: block; height: 100%; background: var(--accent); border-radius: inherit; transition: width .25s ease; }
.progress-small { margin: 14px 10px 4px; }
.progress-small .row { display:flex; justify-content:space-between; font-size:12px; color:var(--muted); margin-bottom:7px; }

.top-title { min-width: 0; }
.top-title strong { display:block; font-size:14px; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
.top-title span { font-size:12px; color:var(--muted); }
.top-actions { display:flex; align-items:center; gap:8px; }
.icon-btn, .btn {
  border: 1px solid var(--line); background: var(--panel); color: var(--text);
  border-radius: 11px; padding: 9px 12px; transition: .18s ease;
}
.icon-btn:hover, .btn:hover { transform: translateY(-1px); border-color: color-mix(in srgb, var(--accent) 45%, var(--line)); }
.btn.primary { background: var(--accent); color: white; border-color: var(--accent); }
.btn.ghost { background: transparent; }
.btn.small { padding: 6px 9px; font-size: 13px; }
.btn.danger { color: var(--bad); }

.hero { padding: 18px 0 10px; }
.kicker { color: var(--accent); font-weight: 750; font-size: 13px; letter-spacing: .04em; text-transform: uppercase; }
h1 { font-size: clamp(32px, 5vw, 56px); line-height: 1.04; letter-spacing: -.045em; margin: 10px 0 18px; }
h2 { font-size: 30px; line-height: 1.15; letter-spacing: -.025em; margin: 38px 0 16px; }
h3 { font-size: 21px; line-height: 1.25; margin: 28px 0 11px; }
h4 { font-size: 16px; margin: 20px 0 8px; }
p { margin: 10px 0 14px; }
.lead { font-size: 19px; color: var(--muted); max-width: 820px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }

.grid { display:grid; gap:16px; }
.grid.two { grid-template-columns: repeat(2, minmax(0,1fr)); }
.grid.three { grid-template-columns: repeat(3, minmax(0,1fr)); }
.grid.four { grid-template-columns: repeat(4, minmax(0,1fr)); }
.card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 19px; box-shadow: var(--shadow);
}
.card.flat { box-shadow:none; }
.card h3, .card h4 { margin-top:0; }
.stat { font-size: 30px; font-weight: 800; letter-spacing: -.04em; }
.stat-label { color: var(--muted); font-size: 13px; }

.callout { border-left: 4px solid var(--info); background: color-mix(in srgb, var(--info) 8%, var(--panel)); padding: 14px 16px; border-radius: 4px 14px 14px 4px; margin: 18px 0; }
.callout.good { border-left-color: var(--good); background: color-mix(in srgb, var(--good) 8%, var(--panel)); }
.callout.warn { border-left-color: var(--warn); background: color-mix(in srgb, var(--warn) 8%, var(--panel)); }
.callout.bad { border-left-color: var(--bad); background: color-mix(in srgb, var(--bad) 8%, var(--panel)); }
.callout strong { display:block; margin-bottom:4px; }

.chip-row { display:flex; flex-wrap:wrap; gap:8px; margin:12px 0; }
.chip { border:1px solid var(--line); background:var(--panel-2); border-radius:999px; padding:5px 9px; font-size:12px; color:var(--muted); }
.chip.accent { color:var(--accent); border-color:color-mix(in srgb,var(--accent) 35%,var(--line)); }

.mastery { display:inline-flex; align-items:center; gap:7px; font-size:12px; font-weight:700; border-radius:999px; padding:5px 9px; }
.mastery.good { color:var(--good); background:color-mix(in srgb,var(--good) 12%,transparent); }
.mastery.warn { color:var(--warn); background:color-mix(in srgb,var(--warn) 12%,transparent); }
.mastery.bad { color:var(--bad); background:color-mix(in srgb,var(--bad) 12%,transparent); }
.mastery.new { color:var(--muted); background:var(--panel-2); }

.module-list { display:grid; gap:13px; }
.module-row { display:grid; grid-template-columns: 52px 1fr auto; gap:16px; align-items:center; padding:16px; border:1px solid var(--line); border-radius:16px; background:var(--panel); text-decoration:none; color:var(--text); }
.module-row:hover { border-color: color-mix(in srgb, var(--accent) 40%, var(--line)); }
.module-index { width:52px; height:52px; border-radius:15px; background:var(--panel-2); display:grid; place-items:center; font-weight:800; color:var(--accent); }
.module-row h3 { margin:0 0 4px; font-size:17px; }
.module-row p { margin:0; font-size:13px; color:var(--muted); }
.module-side { min-width:100px; text-align:right; }

.lesson-shell { display:grid; grid-template-columns: minmax(0,1fr) 230px; gap:30px; align-items:start; }
.lesson-aside { position:sticky; top:96px; }
.lesson-toc a { display:block; text-decoration:none; color:var(--muted); font-size:13px; padding:5px 0; }
.lesson-toc a:hover { color:var(--accent); }
.lesson-meta { display:flex; flex-wrap:wrap; gap:8px 16px; color:var(--muted); font-size:13px; margin:12px 0 24px; }
.lesson-block { margin:28px 0; scroll-margin-top:95px; }
.lesson-block > h2 { font-size:25px; margin-top:0; }
.lesson-nav { display:flex; justify-content:space-between; gap:12px; margin-top:42px; padding-top:24px; border-top:1px solid var(--line); }

.quiz { border:1px solid var(--line); border-radius:16px; padding:18px; background:var(--panel); margin:18px 0; }
.quiz h4 { margin:0 0 12px; }
.option { display:flex; gap:10px; align-items:flex-start; border:1px solid var(--line); border-radius:12px; padding:11px 12px; margin:8px 0; cursor:pointer; }
.option:hover { border-color:color-mix(in srgb,var(--accent) 45%,var(--line)); }
.option input { margin-top:5px; }
.feedback { margin-top:12px; padding:12px 14px; border-radius:12px; font-size:14px; }
.feedback.good { background:color-mix(in srgb,var(--good) 11%,var(--panel)); color:var(--good); }
.feedback.bad { background:color-mix(in srgb,var(--bad) 11%,var(--panel)); color:var(--bad); }
.remediation { margin-top:10px; color:var(--text); }

.formula { overflow:auto; background:var(--panel-2); border-radius:14px; padding:14px 18px; margin:14px 0; }
pre { background:#111827; color:#edf2f7; border-radius:14px; padding:16px; overflow:auto; font-size:13px; line-height:1.55; }
[data-theme="dark"] pre { background:#090d15; }

.interactive { border:1px solid color-mix(in srgb,var(--accent) 25%,var(--line)); border-radius:18px; padding:18px; background:color-mix(in srgb,var(--accent) 4%,var(--panel)); margin:20px 0; }
.interactive h4 { margin-top:0; }
.control-row { display:flex; flex-wrap:wrap; gap:12px 18px; align-items:center; margin:12px 0; }
.control-row label { font-size:13px; color:var(--muted); }
input[type="range"] { width:220px; accent-color:var(--accent); }
.metric-grid { display:grid; grid-template-columns:repeat(4,minmax(0,1fr)); gap:10px; margin-top:12px; }
.metric { background:var(--panel); border:1px solid var(--line); border-radius:12px; padding:10px; }
.metric strong { display:block; font-size:19px; }
.metric span { color:var(--muted); font-size:11px; }
.viz { width:100%; min-height:240px; background:var(--panel); border:1px solid var(--line); border-radius:14px; overflow:hidden; }
.viz svg { width:100%; height:auto; display:block; }

.table-wrap { overflow:auto; border:1px solid var(--line); border-radius:14px; }
table { width:100%; border-collapse:collapse; font-size:14px; background:var(--panel); }
th, td { text-align:left; padding:11px 12px; border-bottom:1px solid var(--line); vertical-align:top; }
th { background:var(--panel-2); font-size:12px; color:var(--muted); position:sticky; top:0; }
tr:last-child td { border-bottom:none; }

.glossary-search { width:100%; padding:12px 14px; border-radius:12px; border:1px solid var(--line); background:var(--panel); color:var(--text); }
.term-grid { display:grid; gap:10px; margin-top:16px; }
.term-row { border:1px solid var(--line); border-radius:14px; padding:14px 16px; background:var(--panel); }
.term-row summary { cursor:pointer; font-weight:750; }
.term-row .term-meta { color:var(--muted); font-size:12px; margin-top:6px; }

.graph-wrap { overflow:auto; border:1px solid var(--line); border-radius:18px; background:var(--panel); padding:8px; }
.graph-wrap svg { min-width:920px; width:100%; height:auto; }
.graph-node { cursor:pointer; }
.graph-node rect { fill:var(--panel-2); stroke:var(--line); }
.graph-node text { fill:var(--text); font-size:12px; }
.graph-edge { stroke:var(--line); stroke-width:1.6; marker-end:url(#arrow); }

.project-card { border:1px solid var(--line); border-radius:18px; padding:18px; background:var(--panel); margin:14px 0; }
.project-card .level { font-size:12px; color:var(--accent); text-transform:uppercase; letter-spacing:.06em; font-weight:750; }

.competency-row { display:grid; grid-template-columns:1fr 130px; gap:18px; align-items:center; padding:14px 0; border-bottom:1px solid var(--line); }
.competency-row:last-child { border-bottom:none; }

.toast { position:fixed; right:22px; bottom:22px; z-index:50; background:var(--text); color:var(--panel); border-radius:12px; padding:10px 14px; opacity:0; transform:translateY(8px); pointer-events:none; transition:.2s ease; box-shadow:var(--shadow); }
.toast.show { opacity:1; transform:none; }

.mobile-menu { display:none; }

@media (max-width: 980px) {
  .sidebar { transform:translateX(-100%); transition:.2s ease; box-shadow:var(--shadow); }
  .sidebar.open { transform:none; }
  .main-shell { margin-left:0; }
  .mobile-menu { display:inline-flex; }
  .lesson-shell { grid-template-columns:1fr; }
  .lesson-aside { display:none; }
  .content { padding:26px 22px 70px; }
  .topbar { padding:10px 18px; }
  .grid.three, .grid.four { grid-template-columns:repeat(2,minmax(0,1fr)); }
}
@media (max-width: 640px) {
  h1 { font-size:38px; }
  h2 { font-size:26px; }
  .grid.two, .grid.three, .grid.four { grid-template-columns:1fr; }
  .module-row { grid-template-columns:46px 1fr; }
  .module-side { grid-column:2; text-align:left; }
  .metric-grid { grid-template-columns:repeat(2,minmax(0,1fr)); }
  .competency-row { grid-template-columns:1fr; }
  .content { padding-left:16px; padding-right:16px; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior:auto !important; transition:none !important; animation:none !important; }
}

/* Application components */
.brand > div:last-child strong { display:block; font-size:15px; }
.brand > div:last-child span { display:block; color:var(--muted); font-size:12px; margin-top:1px; }
.side-nav { display:grid; gap:3px; margin-bottom:20px; }
.side-link { display:flex; align-items:center; gap:10px; color:var(--text); text-decoration:none; padding:9px 10px; border-radius:11px; font-size:14px; }
.side-link:hover { background:var(--panel-2); }
.side-link > span { width:22px; text-align:center; color:var(--muted); }
.side-section-title { text-transform:uppercase; letter-spacing:.08em; font-size:10px; font-weight:800; color:var(--muted); margin:17px 10px 7px; }
.side-modules { display:grid; gap:2px; }
.side-module { display:grid; grid-template-columns:27px 1fr; gap:8px; align-items:start; color:var(--text); text-decoration:none; padding:7px 9px; border-radius:10px; }
.side-module:hover { background:var(--panel-2); }
.side-module > span { color:var(--accent); font-size:11px; font-weight:800; padding-top:2px; }
.side-module b { display:block; font-size:11.5px; line-height:1.25; font-weight:650; }
.side-module small { display:block; color:var(--muted); font-size:10px; margin-top:2px; }
.side-foot { border-top:1px solid var(--line); margin:18px 9px 0; padding-top:12px; display:flex; justify-content:space-between; gap:8px; font-size:11px; }
.link-btn { border:0; padding:0; color:var(--muted); background:transparent; font-size:11px; }
.link-btn:hover { color:var(--bad); }
.hero-actions { display:flex; gap:10px; flex-wrap:wrap; margin:24px 0 10px; }
.hero-actions .btn, .lesson-nav .btn { text-decoration:none; }
.stats { margin-top:26px; }
.compact-row { display:grid; grid-template-columns:260px 1fr; gap:20px; padding:12px 0; border-bottom:1px solid var(--line); }
.compact-row:last-child { border-bottom:0; }
.lesson-goal { background:var(--panel); border:1px solid var(--line); border-radius:14px; padding:14px 16px; margin-bottom:18px; }
.warn-text { color:var(--warn); font-size:13px; }
.module-lessons { display:grid; gap:10px; }
.lesson-line { display:grid; grid-template-columns:42px 1fr auto; gap:14px; align-items:center; text-decoration:none; color:var(--text); padding:13px 15px; border:1px solid var(--line); border-radius:14px; background:var(--panel); }
.lesson-line:hover { border-color:color-mix(in srgb,var(--accent) 40%,var(--line)); }
.lesson-line > div:nth-child(2) b { display:block; font-size:14px; }
.lesson-line > div:nth-child(2) span { display:block; font-size:12px; color:var(--muted); margin-top:2px; }
.lesson-line > div:last-child { display:grid; justify-items:end; gap:5px; }
.lesson-line small { color:var(--muted); font-size:11px; }
.lesson-num { width:34px; height:34px; border-radius:10px; display:grid; place-items:center; background:var(--panel-2); color:var(--accent); font-weight:800; }
.practice-block { background:color-mix(in srgb,var(--good) 4%,var(--panel)); border-left:3px solid var(--good); padding:18px 20px; border-radius:4px 15px 15px 4px; }
.term-chips { display:flex; gap:6px; flex-wrap:wrap; }
.term-chip { border:1px solid var(--line); border-radius:999px; background:var(--panel-2); color:var(--text); padding:5px 8px; font-size:11px; }
.term-chip:hover { border-color:var(--accent); }
.term-chip span { color:var(--accent); font-weight:800; }
.term-pop { position:fixed; right:24px; bottom:24px; width:min(390px,calc(100vw - 32px)); background:var(--panel); border:1px solid var(--line); border-radius:18px; box-shadow:0 24px 70px rgba(0,0,0,.22); padding:20px; z-index:70; opacity:0; transform:translateY(12px); pointer-events:none; transition:.18s ease; }
.term-pop.open { opacity:1; transform:none; pointer-events:auto; }
.term-pop h3 { margin:4px 0 8px; }
.term-close { position:absolute; right:10px; top:8px; border:0; background:transparent; color:var(--muted); font-size:25px; }
.check-list { display:grid; gap:8px; }
.check-list label, .cap-grid label, .switches label { display:flex; align-items:center; gap:8px; }
.source-list { display:grid; gap:10px; }
.source-row { display:grid; grid-template-columns:1fr auto; align-items:center; gap:12px; padding:15px 17px; border:1px solid var(--line); border-radius:14px; background:var(--panel); color:var(--text); text-decoration:none; }
.source-row:hover { border-color:color-mix(in srgb,var(--accent) 45%,var(--line)); }
.source-row b { display:block; }
.source-row span { display:block; color:var(--muted); font-size:12px; margin-top:2px; }
.source-row > span { color:var(--accent); font-size:18px; }
.node-good { stroke:var(--good)!important; }
.node-warn { stroke:var(--warn)!important; }
.node-bad { stroke:var(--bad)!important; }
.node-status { font-size:9px!important; fill:var(--muted)!important; }
.graph-wrap marker polygon { fill:var(--line); }
.split-bars { display:flex; height:52px; border-radius:12px; overflow:hidden; border:1px solid var(--line); margin:15px 0; }
.split-bars > div { display:grid; place-items:center; min-width:42px; font-size:11px; font-weight:700; border-right:1px solid var(--line); background:var(--panel); }
.split-bars > div:nth-child(2) { background:color-mix(in srgb,var(--accent) 8%,var(--panel)); }
.split-bars > div:nth-child(3) { background:color-mix(in srgb,var(--good) 8%,var(--panel)); }
.cluster { opacity:.82; }
.cluster.c0 { fill:#64748b; } .cluster.c1 { fill:#22c55e; } .cluster.c2 { fill:#3b82f6; } .cluster.c3 { fill:#f59e0b; } .cluster.c4 { fill:#a855f7; }
.attention-bars { display:grid; gap:8px; margin-top:16px; }
.attention-bars > div { display:grid; grid-template-columns:70px 1fr 48px; gap:10px; align-items:center; font-size:12px; }
.attention-bars i { height:9px; border-radius:99px; background:var(--panel-2); overflow:hidden; }
.attention-bars i b { display:block; height:100%; background:var(--accent); border-radius:inherit; }
.step-buttons { display:flex; gap:7px; flex-wrap:wrap; margin:12px 0; }
.rag-built { min-height:64px; border:1px dashed var(--line); border-radius:12px; padding:12px; background:var(--panel); margin:10px 0; font-size:13px; }
.seg-demo { height:210px; display:grid; place-items:center; background:var(--panel); border:1px solid var(--line); border-radius:14px; margin-bottom:12px; }
.part { width:260px; height:120px; border-radius:60px 18px 18px 60px; background:linear-gradient(135deg,#a8b0bb,#667180); position:relative; box-shadow:inset 0 0 0 10px rgba(255,255,255,.17); }
.defect { position:absolute; width:54px; height:8px; background:var(--bad); transform:rotate(-22deg); left:125px; top:54px; border-radius:99px; }
.seg-demo[data-mode="Классификация"] .part { outline:4px solid var(--bad); outline-offset:5px; }
.seg-demo[data-mode="Обнаружение"] .defect { outline:3px solid var(--warn); outline-offset:12px; }
.seg-demo[data-mode="Сегментация"] .defect { box-shadow:0 0 0 4px color-mix(in srgb,var(--bad) 30%,transparent); }
.switches { display:flex; flex-wrap:wrap; gap:16px; margin:14px 0; }
.tco-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:10px 18px; }
.tco-grid label { display:grid; grid-template-columns:1fr 95px; gap:10px; align-items:center; font-size:13px; }
.tco-grid input[type="number"] { width:100%; padding:7px 9px; border:1px solid var(--line); border-radius:9px; background:var(--panel); color:var(--text); }
.big-result { font-size:22px; margin-top:18px; padding:14px; border-radius:12px; background:var(--panel); border:1px solid var(--line); }
.inadmissible { opacity:.42; text-decoration:line-through; }
.weights label { display:grid; gap:3px; }
.weights input[type="range"] { width:135px; }
.cap-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:8px 18px; margin-bottom:16px; }

@media (max-width: 720px) {
  .compact-row { grid-template-columns:1fr; gap:2px; }
  .lesson-line { grid-template-columns:38px 1fr; }
  .lesson-line > div:last-child, .lesson-line > .mastery { grid-column:2; justify-self:start; justify-items:start; }
  .tco-grid, .cap-grid { grid-template-columns:1fr; }
  .term-pop { right:16px; bottom:16px; }
}