/* edu.xpertnet.ai — дизайн-система xpertnet.ai (nextjs/app/globals.css): тёмная тема по умолчанию,
   один акцент #0d99ff, Inter, заголовки weight 500/600 (никогда 800), pill-кнопки, карточки 20px. */
:root {
  --bg: #161a1d; --alt: #1d2126; --card: #1b2025; --card2: #1d2126;
  --fg: #f2f4f6; --muted: #8b929a; --sub: #c6cbd1; --line: #2c3138; --line2: #23282e;
  --accent: #0d99ff; --accent-soft: rgba(13,153,255,0.16); --accent-ink: #5ab5ff; --hdr: rgba(22,26,29,0.88);
  --ok: #34d399; --ok-soft: rgba(52,211,153,0.14); --warn: #fbbf24; --warn-soft: rgba(251,191,36,0.14);
  --err: #f87171; --err-soft: rgba(248,113,113,0.14);
  --font-body: 'Inter', -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  --weight-heading: 500; --weight-section: 600; --tracking-heading: -0.02em;
  --container: 1200px; --pad-x: 24px;
  --radius-card: 20px; --radius-card-lg: 24px; --radius-sm: 12px; --radius-pill: 999px;
  --shadow-card-hover: 0 16px 40px rgba(0,0,0,0.45); --card-border: #2c333b;
  --footer-bg: #101316; --footer-fg: #8b929a;
}
[data-theme="light"] {
  --bg: #f7f8fa; --alt: #ffffff; --card: #ffffff; --card2: #fbfcfd;
  --fg: #171a1d; --muted: #5c636b; --sub: #454b52; --line: #e6e9ee; --line2: #eef1f4;
  --accent-soft: rgba(13,153,255,0.12); --accent-ink: #0b7fd6; --hdr: rgba(247,248,250,0.9);
  --ok: #059669; --ok-soft: rgba(5,150,105,0.1); --warn: #b45309; --warn-soft: rgba(180,83,9,0.1);
  --err: #dc2626; --err-soft: rgba(220,38,38,0.1);
  --shadow-card-hover: 0 12px 32px rgba(23,26,29,0.10); --card-border: #e6e9ee;
  --footer-bg: #eef1f4; --footer-fg: #6b727b;
}
* { box-sizing: border-box; }
html { scrollbar-gutter: stable; }
html, body { margin: 0; background: var(--bg); color: var(--fg); font-family: var(--font-body); line-height: 1.55; -webkit-font-smoothing: antialiased; font-variant-numeric: tabular-nums; }
body { min-height: 100vh; display: flex; flex-direction: column; }
main { flex: 1; }
a { color: var(--fg); text-decoration: none; transition: color .15s ease; }
a:hover { color: var(--accent); }
h1, h2, h3, h4 { letter-spacing: var(--tracking-heading); margin: 0; line-height: 1.15; font-weight: var(--weight-heading); text-wrap: balance; }
h1 { font-size: clamp(30px, 4vw, 44px); letter-spacing: -0.03em; }
h2 { font-size: clamp(22px, 2.4vw, 28px); font-weight: var(--weight-section); }
h3 { font-size: 18px; font-weight: var(--weight-section); letter-spacing: -0.005em; }
h4 { font-size: 15px; font-weight: 600; }
p { margin: 0; }
code, pre { font-family: var(--font-mono); font-size: .9em; }
code { background: var(--line2); border-radius: 6px; padding: 1px 6px; }
pre { background: var(--alt); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 12px 14px; overflow-x: auto; white-space: pre; }
pre code { background: none; padding: 0; }
.container { max-width: var(--container); margin: 0 auto; padding: 0 var(--pad-x); width: 100%; }
.narrow { max-width: 860px; }
.section { padding: 40px 0; }
.muted { color: var(--muted); }
.sub { color: var(--sub); }
.small { font-size: 13px; }
.accent { color: var(--accent); }
.mono { font-family: var(--font-mono); }
.hidden { display: none !important; }
.kicker { display: inline-block; color: var(--accent); font-weight: 600; font-size: 12.5px; letter-spacing: .08em; text-transform: uppercase; margin-bottom: 10px; }
.section-title::before { content: ''; display: block; width: 44px; height: 3px; border-radius: 2px; background: var(--accent); opacity: .7; margin-bottom: 14px; }
.hero-bg { background: radial-gradient(900px 420px at 78% 8%, rgba(13,153,255,0.08), transparent 65%), var(--bg); }
.dotted-bg { background-image: radial-gradient(rgba(13,153,255,0.06) 1px, transparent 1px); background-size: 28px 28px; }

/* ---------- шапка ---------- */
.hdr { position: sticky; top: 0; z-index: 50; background: var(--hdr); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }
.hdr .container { min-height: 64px; display: flex; align-items: center; gap: 20px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; letter-spacing: -0.02em; white-space: nowrap; }
.brand svg { flex-shrink: 0; }
.brand .dot { color: var(--accent); }
.brand .edu { font-weight: 500; color: var(--muted); font-size: 13px; margin-left: 2px; padding: 2px 8px; border: 1px solid var(--line); border-radius: var(--radius-pill); }
.nav { display: flex; align-items: center; gap: 4px; margin-left: 8px; }
.nav a { padding: 8px 12px; border-radius: var(--radius-pill); font-size: 14.5px; font-weight: 500; color: var(--sub); }
.nav a:hover { color: var(--fg); background: var(--line2); }
.nav a.active { color: var(--fg); background: var(--accent-soft); }
.hdr .spacer { flex: 1; }
.hdr .tools { display: flex; align-items: center; gap: 8px; }
.icon-btn { width: 38px; height: 38px; border-radius: 50%; border: 1px solid var(--line); background: var(--card2); color: var(--fg); cursor: pointer; display: inline-flex; align-items: center; justify-content: center; padding: 0; transition: border-color .15s, background .15s; }
.icon-btn:hover { border-color: var(--accent); }
.lang-btn { height: 38px; padding: 0 12px; border-radius: var(--radius-pill); border: 1px solid var(--line); background: var(--card2); color: var(--fg); cursor: pointer; font: inherit; font-size: 13px; font-weight: 600; letter-spacing: .04em; }
.lang-btn:hover { border-color: var(--accent); }
.user-chip { display: inline-flex; align-items: center; gap: 8px; height: 38px; padding: 0 12px 0 6px; border-radius: var(--radius-pill); border: 1px solid var(--line); background: var(--card2); color: var(--fg); cursor: pointer; font: inherit; font-size: 13.5px; }
.user-chip .avatar { width: 26px; height: 26px; border-radius: 50%; background: var(--accent); color: #fff; display: inline-flex; align-items: center; justify-content: center; font-weight: 600; font-size: 12px; }
.burger { display: none; }
@media (max-width: 860px) {
  .nav, .user-chip .name { display: none; }
  .burger { display: inline-flex; }
  .mobile-nav { display: flex; flex-direction: column; gap: 4px; padding: 8px 0 12px; border-top: 1px solid var(--line); }
  .mobile-nav a { padding: 10px 12px; border-radius: var(--radius-sm); font-weight: 500; }
  .mobile-nav a.active { background: var(--accent-soft); }
}
.mobile-nav { display: none; }
.mobile-nav.open { display: flex; }

/* ---------- футер ---------- */
.ftr { background: var(--footer-bg); color: var(--footer-fg); padding: 28px 0; font-size: 12.5px; margin-top: 48px; }
.ftr .container { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; align-items: center; }
.ftr a { color: var(--footer-fg); text-decoration: underline; text-underline-offset: 3px; }

/* ---------- кнопки ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 11px 22px; border-radius: var(--radius-pill); border: 1px solid var(--line); background: var(--card2); color: var(--fg); font: inherit; font-size: 14.5px; font-weight: 600; cursor: pointer; transition: background .15s, border-color .15s, color .15s, transform .15s; white-space: nowrap; text-decoration: none; }
.btn:hover { border-color: var(--accent); color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: #2aa5ff; color: #fff; }
.btn.ghost { background: transparent; }
.btn.danger { color: var(--err); border-color: var(--err); background: transparent; }
.btn.danger:hover { background: var(--err-soft); }
.btn.sm { padding: 7px 14px; font-size: 13px; }
.btn.lg { padding: 14px 30px; font-size: 16px; }
.btn.block { width: 100%; }
.btn:disabled { opacity: .45; cursor: not-allowed; }
.btn:disabled:hover { border-color: var(--line); color: var(--fg); }
.btn.primary:disabled:hover { background: var(--accent); color: #fff; }
.btn-row { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }

/* ---------- формы ---------- */
label.f { display: block; margin-top: 12px; }
label.f > span { display: block; font-size: 12.5px; color: var(--muted); margin-bottom: 6px; font-weight: 500; }
input:not([type=checkbox], [type=radio], [type=file]), select, textarea { width: 100%; padding: 11px 14px; border-radius: var(--radius-sm); border: 1px solid var(--line); background: var(--alt); color: var(--fg); font: inherit; font-size: 15px; outline: none; transition: border-color .15s; }
input:focus, select:focus, textarea:focus { border-color: var(--accent); }
textarea { resize: vertical; min-height: 80px; }
.chk { display: inline-flex; align-items: center; gap: 8px; font-size: 14px; cursor: pointer; }
.chk input { width: 16px; height: 16px; accent-color: var(--accent); }
.err { color: var(--err); font-size: 13.5px; }
.ok { color: var(--ok); }

/* ---------- карточки ---------- */
.card { background: var(--card); border: 1px solid var(--card-border); border-radius: var(--radius-card); padding: 22px 24px; box-shadow: inset 0 1px 0 rgba(255,255,255,0.04); transition: border-color .15s ease, transform .15s ease, box-shadow .15s ease; }
[data-theme="light"] .card { box-shadow: 0 1px 2px rgba(23,26,29,0.04); }
.card.hover:hover, a.card:hover { border-color: var(--accent); box-shadow: var(--shadow-card-hover); transform: translateY(-2px); }
a.card { display: block; color: inherit; }
.card.tight { padding: 16px 18px; }
.grid { display: grid; gap: 20px; }
.grid.c2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); }
.grid.c3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr)); }
.grid.c4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr)); }
.stack { display: flex; flex-direction: column; gap: 14px; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.between { justify-content: space-between; }
.badge { display: inline-flex; align-items: center; gap: 5px; padding: 3px 10px; border-radius: var(--radius-pill); font-size: 12px; font-weight: 600; background: var(--line2); color: var(--sub); white-space: nowrap; }
.badge.ok { background: var(--ok-soft); color: var(--ok); }
.badge.warn { background: var(--warn-soft); color: var(--warn); }
.badge.bad { background: var(--err-soft); color: var(--err); }
.badge.accent { background: var(--accent-soft); color: var(--accent-ink); }
.dom-tag { display: inline-flex; align-items: center; gap: 6px; padding: 3px 10px; border-radius: var(--radius-pill); font-size: 12px; font-weight: 600; color: #fff; background: var(--accent); }
.dom-tag i { width: 8px; height: 8px; border-radius: 50%; background: rgba(255,255,255,.7); }
.stat { display: flex; flex-direction: column; gap: 2px; }
.stat .v { font-size: 30px; font-weight: 600; letter-spacing: -0.03em; line-height: 1.1; }
.stat .l { font-size: 12.5px; color: var(--muted); }
.stat.sm .v { font-size: 22px; }
.bar { height: 8px; border-radius: 4px; background: var(--line2); overflow: hidden; }
.bar > i { display: block; height: 100%; border-radius: 4px; background: var(--accent); transition: width .4s ease; }
.dom-row { display: grid; grid-template-columns: 1fr auto; gap: 4px 12px; align-items: center; font-size: 13.5px; padding: 6px 0; }
.dom-row .bar { grid-column: 1 / -1; }
.progress-ring { position: relative; width: 84px; height: 84px; }
.progress-ring svg { transform: rotate(-90deg); }
.progress-ring b { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; font-size: 18px; font-weight: 600; }

/* ---------- таблицы ---------- */
.tbl-wrap { overflow-x: auto; }
table.data { width: 100%; border-collapse: collapse; font-size: 13.5px; }
table.data th, table.data td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); vertical-align: middle; }
table.data th { font-size: 12px; color: var(--muted); font-weight: 600; letter-spacing: .04em; text-transform: uppercase; }
table.data tr:hover td { background: var(--line2); }
table.data td.num, table.data th.num { text-align: right; }

/* ---------- вкладки ---------- */
.tabs { display: flex; gap: 6px; flex-wrap: wrap; border-bottom: 1px solid var(--line); margin-bottom: 20px; }
.tabs button { background: none; border: none; border-bottom: 2px solid transparent; padding: 10px 14px; margin-bottom: -1px; color: var(--muted); font: inherit; font-size: 14.5px; font-weight: 500; cursor: pointer; }
.tabs button.active { color: var(--fg); border-bottom-color: var(--accent); }
.tabs button:hover { color: var(--fg); }
.pills { display: flex; gap: 8px; flex-wrap: wrap; }
.pill { padding: 6px 14px; border-radius: var(--radius-pill); border: 1px solid var(--line); background: var(--card2); color: var(--sub); font: inherit; font-size: 13px; font-weight: 500; cursor: pointer; }
.pill.active { background: var(--fg); color: var(--bg); border-color: var(--fg); }
.pill:hover { border-color: var(--accent); }

/* ---------- режимы тренажёра ---------- */
.mode-card { display: flex; flex-direction: column; gap: 10px; cursor: pointer; }
.mode-card h3 { display: flex; align-items: center; gap: 10px; }
.mode-card .ic { width: 36px; height: 36px; border-radius: 10px; background: var(--accent-soft); color: var(--accent-ink); display: inline-flex; align-items: center; justify-content: center; flex-shrink: 0; }
.mode-card p { color: var(--sub); font-size: 14px; }
.mode-card .foot { margin-top: auto; display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); }
.drill-list { display: grid; gap: 8px; grid-template-columns: repeat(auto-fill, minmax(min(100%, 240px), 1fr)); }
.drill { display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-radius: var(--radius-sm); border: 1px solid var(--line); border-left: 3px solid var(--accent); background: var(--card2); cursor: pointer; font-size: 13.5px; text-align: left; color: var(--fg); font-family: inherit; }
.drill:hover { border-color: var(--accent); }
.drill .n { font-weight: 600; min-width: 34px; color: var(--muted); font-size: 12px; }
.drill .t { flex: 1; }
.drill .c { font-size: 12px; color: var(--muted); }
.drill .pct { font-size: 12px; font-weight: 600; }

/* ---------- квиз ---------- */
.quiz-top { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; padding: 14px 0; }
.quiz-top .progress { font-weight: 600; font-size: 14px; }
.timer { font-family: var(--font-mono); font-weight: 600; font-size: 15px; padding: 6px 12px; border-radius: var(--radius-pill); background: var(--line2); }
.timer.warn { background: var(--err-soft); color: var(--err); animation: pulse 1s infinite; }
@keyframes pulse { 50% { opacity: .55; } }
.navigator { display: flex; flex-wrap: wrap; gap: 5px; margin: 6px 0 16px; }
.navigator button { width: 30px; height: 30px; border-radius: 8px; border: 1px solid var(--line); background: var(--card2); color: var(--sub); font: inherit; font-size: 11.5px; font-weight: 600; cursor: pointer; position: relative; padding: 0; }
.navigator button.answered { background: var(--accent-soft); color: var(--accent-ink); border-color: transparent; }
.navigator button.correct { background: var(--ok-soft); color: var(--ok); border-color: transparent; }
.navigator button.wrong { background: var(--err-soft); color: var(--err); border-color: transparent; }
.navigator button.current { outline: 2px solid var(--accent); outline-offset: 1px; }
.navigator button.marked::after { content: ''; position: absolute; top: 3px; right: 3px; width: 6px; height: 6px; border-radius: 50%; background: var(--warn); }
.q-card { padding: 26px 28px; }
.q-text { font-size: 17.5px; line-height: 1.55; margin: 14px 0 20px; white-space: pre-wrap; }
.rich { white-space: pre-wrap; }
.rich pre { white-space: pre; margin: 8px 0; }
.opt { display: flex; gap: 14px; align-items: flex-start; padding: 13px 16px; border: 1px solid var(--line); border-radius: 14px; margin-bottom: 8px; cursor: pointer; background: var(--card2); transition: border-color .15s, background .15s; font-size: 15px; line-height: 1.5; user-select: text; }
.opt:hover { border-color: var(--accent); }
.opt .letter { width: 30px; height: 30px; border-radius: 50%; flex-shrink: 0; display: inline-flex; align-items: center; justify-content: center; font-weight: 600; font-size: 13px; background: var(--line2); color: var(--sub); }
.opt.multi .letter { border-radius: 8px; }
.opt.selected { border-color: var(--accent); background: var(--accent-soft); }
.opt.selected .letter { background: var(--accent); color: #fff; }
.opt.correct { border-color: var(--ok); background: var(--ok-soft); }
.opt.correct .letter { background: var(--ok); color: #fff; }
.opt.wrong { border-color: var(--err); background: var(--err-soft); }
.opt.wrong .letter { background: var(--err); color: #fff; }
.opt.locked { cursor: default; }
.opt.locked:hover { border-color: var(--line); }
.opt.locked.correct:hover { border-color: var(--ok); }
.opt.locked.wrong:hover { border-color: var(--err); }
.match-row { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; padding: 10px 14px; border: 1px solid var(--line); border-radius: 14px; margin-bottom: 8px; background: var(--card2); font-size: 14.5px; }
.match-row .choices { display: flex; gap: 6px; flex-wrap: wrap; }
.match-row .choices button { padding: 6px 12px; border-radius: var(--radius-pill); border: 1px solid var(--line); background: var(--alt); color: var(--sub); font: inherit; font-size: 12.5px; font-weight: 600; cursor: pointer; }
.match-row .choices button.sel { background: var(--accent); border-color: var(--accent); color: #fff; }
.match-row.correct { border-color: var(--ok); background: var(--ok-soft); }
.match-row.wrong { border-color: var(--err); background: var(--err-soft); }
.match-row .key { font-size: 12px; color: var(--muted); }
@media (max-width: 640px) { .match-row { grid-template-columns: 1fr; } }
.hint { font-size: 13px; color: var(--muted); margin: 6px 0 12px; }
.hint.ready { color: var(--ok); }
.box { border-radius: 14px; padding: 16px 18px; margin-top: 16px; border: 1px solid var(--line); background: var(--alt); }
.box.validator { border-color: var(--warn); background: var(--warn-soft); }
.box.explain.good { border-color: var(--ok); background: var(--ok-soft); }
.box.explain.bad { border-color: var(--err); background: var(--err-soft); }
.box h4 { margin-bottom: 8px; }
.box .note { margin-top: 10px; padding: 10px 12px; border-radius: 10px; background: var(--warn-soft); color: var(--warn); font-size: 13px; }
.proof { margin-top: 10px; font-size: 13px; word-break: break-word; }
.proof a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }
.proof q { display: block; margin-top: 4px; color: var(--sub); font-style: italic; }
.score-bar { display: flex; flex-wrap: wrap; gap: 8px 18px; font-size: 13px; color: var(--muted); margin-top: 14px; }
.score-bar b { color: var(--fg); }
.result-hero { text-align: center; padding: 30px 0 10px; }
.result-hero .score { font-size: clamp(56px, 10vw, 96px); font-weight: 600; letter-spacing: -0.04em; line-height: 1; }
.result-hero .score.pass { color: var(--ok); }
.result-hero .score.fail { color: var(--err); }
.result-hero .label { font-size: 16px; color: var(--sub); margin-top: 8px; }
.missed { border: 1px solid var(--line); border-radius: 14px; padding: 14px 16px; margin-bottom: 10px; background: var(--card2); font-size: 14px; }
.missed .yours { color: var(--err); margin-top: 6px; }
.missed .right { color: var(--ok); margin-top: 4px; }
.missed details { margin-top: 8px; }
.missed summary { cursor: pointer; color: var(--accent); font-size: 13px; }
.compact { font-family: var(--font-mono); font-size: 12px; word-break: break-all; color: var(--sub); background: var(--alt); border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; }

/* ---------- материалы ---------- */
.sheet h4 { margin-bottom: 8px; }
.sheet ul { margin: 0; padding-left: 18px; font-size: 14px; color: var(--sub); }
.sheet li { margin: 4px 0; }
.sheet li.src { list-style: none; margin-left: -18px; font-size: 12.5px; color: var(--muted); }
.mm { display: grid; grid-template-columns: 40px 1fr; gap: 12px; padding: 14px 0; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.mm .n { width: 34px; height: 34px; border-radius: 10px; background: var(--accent-soft); color: var(--accent-ink); display: inline-flex; align-items: center; justify-content: center; font-weight: 600; }
.mm .d { color: var(--sub); margin-top: 4px; }
.ap { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 14px; }
.ap .bad { color: var(--err); } .ap .good { color: var(--ok); }
.ap .bad::before { content: '✕ '; } .ap .good::before { content: '✓ '; }
@media (max-width: 640px) { .ap { grid-template-columns: 1fr; } }

/* ---------- уроки ---------- */
.lesson-list { display: grid; gap: 8px; }
.lesson-row { display: flex; gap: 12px; align-items: center; padding: 12px 16px; border: 1px solid var(--line); border-left: 3px solid var(--accent); border-radius: var(--radius-sm); background: var(--card2); cursor: pointer; color: var(--fg); font: inherit; text-align: left; }
.lesson-row:hover { border-color: var(--accent); }
.lesson-row .n { font-weight: 600; min-width: 36px; color: var(--muted); font-size: 12.5px; }
.lesson-row .t { flex: 1; font-weight: 500; }
.lesson-row .s { font-size: 12.5px; color: var(--muted); }
.lesson { max-width: 860px; }
.lesson .md { font-size: 15.5px; line-height: 1.65; color: var(--sub); }
.lesson .md p { margin: 0 0 12px; }
.lesson .md h3, .lesson .md h4 { color: var(--fg); margin: 20px 0 8px; }
.lesson .md ul, .lesson .md ol { margin: 0 0 12px; padding-left: 22px; }
.lesson .md li { margin: 4px 0; }
.lesson .md pre { margin: 0 0 12px; }
.lesson .md .tbl-wrap { margin: 0 0 14px; }
.lesson .md table.data th, .lesson .md table.data td { vertical-align: top; font-size: 14px; }
.lesson .md table.data tr:hover td { background: transparent; }
.lesson .md a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }
.lesson .facts li { margin: 6px 0; }
.lesson .facts a { color: var(--accent); font-size: 12.5px; margin-left: 6px; white-space: nowrap; }
.md-inline code, .lesson .facts code, .lesson .trap code { background: var(--line2); border-radius: 5px; padding: 1px 5px; }
.md-inline a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }
.lesson .ours { border-left: 3px solid var(--warn); }
.lesson .trap { display: flex; gap: 10px; padding: 8px 0; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.lesson .trap::before { content: '⚠'; color: var(--warn); }

/* ---------- графики ---------- */
.chart { width: 100%; height: auto; }
.heat { display: grid; grid-template-columns: repeat(15, 1fr); gap: 4px; }
.heat i { display: block; aspect-ratio: 1; border-radius: 3px; background: var(--line2); }
.heat i.l1 { background: rgba(13,153,255,.3); } .heat i.l2 { background: rgba(13,153,255,.55); } .heat i.l3 { background: var(--accent); }

/* ---------- диалоги, тосты ---------- */
dialog { border: 1px solid var(--line); border-radius: var(--radius-card); background: var(--card); color: var(--fg); padding: 24px 26px; max-width: 520px; width: calc(100% - 32px); }
dialog::backdrop { background: rgba(0,0,0,.55); backdrop-filter: blur(4px); }
.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); background: var(--fg); color: var(--bg); padding: 10px 18px; border-radius: var(--radius-pill); font-size: 14px; font-weight: 500; z-index: 100; box-shadow: 0 8px 24px rgba(0,0,0,.3); opacity: 0; transition: opacity .2s; pointer-events: none; }
.toast.show { opacity: 1; }
.banner { display: flex; align-items: center; gap: 10px; padding: 10px 14px; border-radius: var(--radius-sm); font-size: 13.5px; }
.banner.warn { background: var(--warn-soft); color: var(--warn); }
.banner.info { background: var(--accent-soft); color: var(--accent-ink); }
.banner.err { background: var(--err-soft); color: var(--err); }
.install-bar { position: fixed; left: 16px; right: 16px; bottom: 16px; z-index: 90; display: flex; gap: 12px; align-items: center; padding: 12px 16px; border-radius: 16px; background: var(--card); border: 1px solid var(--accent); box-shadow: var(--shadow-card-hover); font-size: 14px; max-width: 520px; margin: 0 auto; }
.dropzone { border: 2px dashed var(--line); border-radius: var(--radius-card); padding: 28px; text-align: center; color: var(--muted); cursor: pointer; transition: border-color .15s, background .15s; }
.dropzone.over, .dropzone:hover { border-color: var(--accent); background: var(--accent-soft); }
.report { font-family: var(--font-mono); font-size: 12px; white-space: pre-wrap; max-height: 260px; overflow: auto; padding: 12px; border-radius: 10px; background: var(--alt); border: 1px solid var(--line); }
.skeleton { background: linear-gradient(90deg, var(--line2) 25%, var(--line) 50%, var(--line2) 75%); background-size: 200% 100%; animation: sk 1.2s infinite; border-radius: 10px; min-height: 80px; }
@keyframes sk { to { background-position: -200% 0; } }
@media print { .hdr, .ftr, .btn, .navigator { display: none !important; } }
@media (max-width: 640px) { :root { --pad-x: 16px; } .q-card { padding: 18px 16px; } .q-text { font-size: 16px; } .section { padding: 24px 0; } .card { padding: 18px 18px; } }