/* Черепашка — дизайн-токены.
   Layout: школьная доска. Колонка текста по центру, справа на «полке» шпаргалка (оглавление).
   Светлая тема — маркерная доска (белая, маркеры синий/красный/зелёный, жёлтый выделитель),
   тёмная — меловая доска (зелёная, мел белый/жёлтый/розовый/голубой). Инструменты — в окне редактора. */
:root {
  --bg: #f6f7f2;
  --bg-2: #ffffff;
  --panel: #eef0e8;
  --ink: #1f2a2e;
  --ink-2: #4a565b;
  --ink-3: #7b868a;
  --line: #d9ddd2;
  --c-blue: #1f5fbf;
  --c-red: #cf3a3c;
  --c-green: #23845a;
  --c-yellow: #ffe46b;
  --hl: rgba(255, 228, 107, .65);
  --shelf: #c9a979;
  --ide: #1c2026;
  --ide-2: #252a32;
  --ide-3: #2f3540;
  --ide-ink: #e8ecef;
  --ide-dim: #9aa4ad;
  --ok: #23845a; --ok-bg: #e2f3ea; --bad: #c43c3c; --bad-bg: #fbe8e6;
  --note-y: #fff1a8; --note-b: #d9ecff; --note-ink: #2b2a20;
  --shadow: 0 1px 0 rgba(31, 42, 46, .06), 0 10px 26px -14px rgba(31, 42, 46, .35);
  --f-head: "Balsamiq Sans", "Comic Sans MS", "Segoe UI", system-ui, sans-serif;
  --f-body: "Nunito", "Segoe UI", system-ui, -apple-system, sans-serif;
  --f-code: "JetBrains Mono", "Consolas", "Menlo", monospace;
  --r-1: 6px; --r-2: 12px; --r-3: 18px;
  --measure: 70ch;
  /* цвета разделов (как категории блоков) */
  --k-start: #e0742f; --k-scratch: #d4a017; --k-python: #2f6fd1; --k-praktikum: #23845a;
  --k-informatika: #7a4fc9; --k-oshibki: #cf3a3c; --k-roditelyam: #b0587f; --k-spravochnik: #4a7d8c; --k-trenazhery: #1d8f8f;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #1d3a2f; --bg-2: #234536; --panel: #284c3d; --ink: #eef2ea; --ink-2: #c9d6cc; --ink-3: #93ab9e; --line: #3b6150;
    --c-blue: #9cc9f2; --c-red: #f29ca3; --c-green: #a8e0b8; --c-yellow: #f4d35e; --hl: rgba(244, 211, 94, .28);
    --shelf: #8a6b45; --ok: #8fdcae; --ok-bg: #1f4b36; --bad: #ffa3a3; --bad-bg: #4d2626;
    --note-y: #f4e48a; --note-b: #c5e0f7; --note-ink: #2b2a20;
    --shadow: 0 1px 0 rgba(0,0,0,.25), 0 12px 30px -14px rgba(0,0,0,.6);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #1d3a2f; --bg-2: #234536; --panel: #284c3d; --ink: #eef2ea; --ink-2: #c9d6cc; --ink-3: #93ab9e; --line: #3b6150;
  --c-blue: #9cc9f2; --c-red: #f29ca3; --c-green: #a8e0b8; --c-yellow: #f4d35e; --hl: rgba(244, 211, 94, .28);
  --shelf: #8a6b45; --ok: #8fdcae; --ok-bg: #1f4b36; --bad: #ffa3a3; --bad-bg: #4d2626;
  --note-y: #f4e48a; --note-b: #c5e0f7; --note-ink: #2b2a20;
  --shadow: 0 1px 0 rgba(0,0,0,.25), 0 12px 30px -14px rgba(0,0,0,.6);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 5.5rem; }
body {
  margin: 0; background-color: var(--bg); color: var(--ink);
  background-image: radial-gradient(1200px 500px at 15% -10%, color-mix(in srgb, var(--bg-2) 70%, transparent), transparent 70%),
                    radial-gradient(900px 600px at 110% 30%, color-mix(in srgb, var(--panel) 60%, transparent), transparent 70%);
  background-attachment: fixed;
  font: 400 1.075rem/1.7 var(--f-body);
}
img, svg { max-width: 100%; }
a { color: var(--c-blue); text-underline-offset: 3px; text-decoration-thickness: 1.5px; }
a:hover { color: var(--c-red); }
:focus-visible { outline: 3px solid var(--c-blue); outline-offset: 2px; border-radius: 4px; }
h1, h2, h3 { font-family: var(--f-head); font-weight: 700; line-height: 1.18; text-wrap: balance; overflow-wrap: break-word; hyphens: auto; }
code, kbd, pre { font-family: var(--f-code); }
.wrap { width: 100%; max-width: 1220px; margin-inline: auto; padding-inline: max(16px, 4vw); }
.skip { position: absolute; left: -999px; top: 0; background: var(--ink); color: var(--bg); padding: .5rem 1rem; z-index: 99; }
.skip:focus { left: 16px; }
.muted { color: var(--ink-3); }

/* ── Шапка: панель с вкладками ─────────────────── */
.top { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 30; background: color-mix(in srgb, var(--bg) 90%, transparent); backdrop-filter: blur(8px); border-bottom: 2px solid var(--line); }
.top .wrap { display: flex; align-items: center; gap: 1rem; min-height: 66px; }
.logo { display: flex; align-items: center; gap: .55rem; text-decoration: none; color: var(--ink); font: 700 1.3rem var(--f-head); }
.logo svg { width: 36px; height: 36px; flex: none; }
.nav { display: flex; gap: .15rem; margin-left: auto; flex-wrap: wrap; }
.nav a { position: relative; text-decoration: none; color: var(--ink-2); padding: .5rem .7rem; font-weight: 700; font-size: .95rem; border-radius: var(--r-1); }
.nav a:hover { color: var(--ink); background: var(--panel); }
.nav a[aria-current="page"] { color: var(--ink); }
.nav a[aria-current="page"]::after { content: ""; position: absolute; left: .6rem; right: .6rem; bottom: .15rem; height: 4px; border-radius: 4px; background: var(--c-red); transform: rotate(-1deg); }
.icon-btn { flex: none; width: 42px; height: 42px; display: grid; place-items: center; border: 2px solid var(--line); background: var(--bg-2); color: var(--ink); border-radius: var(--r-2); cursor: pointer; text-decoration: none; }
.icon-btn svg { width: 19px; height: 19px; }
.menu-btn { display: none; }
@media (max-width: 1000px) {
  .menu-btn { display: grid; margin-left: auto; }
  .nav { display: none; position: absolute; left: 0; right: 0; top: 100%; flex-direction: column; background: var(--bg-2); border-bottom: 2px solid var(--line); padding: .75rem max(16px, 4vw); box-shadow: var(--shadow); }
  .nav.open { display: flex; }
}

/* ── Шапка статьи ──────────────────────────────── */
.crumbs { font-size: .88rem; color: var(--ink-3); padding-top: 1.4rem; display: flex; flex-wrap: wrap; gap: .4rem; }
.crumbs a { color: var(--ink-2); }
.page-head { padding-block: .8rem 1.4rem; max-width: 900px; }
.page-head h1 { font-size: clamp(1.9rem, 1.2rem + 2.8vw, 3.1rem); margin: 0 0 1rem; }
.page-head h1 .hl, .hl { background: linear-gradient(transparent 55%, var(--hl) 55%, var(--hl) 92%, transparent 92%); }
.meta-line { display: flex; flex-wrap: wrap; gap: .4rem .6rem; margin-bottom: 1rem; }
.chip { display: inline-flex; align-items: center; gap: .35rem; font-size: .82rem; font-weight: 700; padding: .2rem .65rem; border-radius: 999px; background: var(--panel); color: var(--ink-2); }
.chip.k { color: #fff; }
.lead p { font-size: 1.22rem; line-height: 1.6; max-width: var(--measure); margin: 0; text-align: left !important; }

/* ── Раскладка: колонка + полка-шпаргалка справа ── */
.sheet { display: grid; grid-template-columns: minmax(0, 1fr) 270px; gap: 2.5rem; padding-block: 1.5rem 4rem; align-items: start; }
.sheet > .body { min-width: 0; }
.sheet > .shelf { position: sticky; top: 90px; }
@media (max-width: 1000px) { .sheet { grid-template-columns: minmax(0, 1fr); } .sheet > .shelf { position: static; order: -1; } }
.shelf .crib { background: var(--bg-2); border: 2px solid var(--line); border-radius: var(--r-2); padding: 1rem 1.1rem; box-shadow: var(--shadow); }
.shelf .crib::after { content: ""; display: block; height: 10px; margin: 1rem -1.1rem -1rem; background: var(--shelf); border-radius: 0 0 10px 10px; }
.crib-title { font: 700 1.05rem var(--f-head); margin: 0 0 .5rem; }
.toc ol { margin: 0; padding-left: 1.3rem; display: grid; gap: .25rem; font-size: .92rem; }
.toc a { color: var(--ink-2); text-decoration: none; }
.toc a:hover, .toc a.on { color: var(--ink); text-decoration: underline; text-decoration-color: var(--c-red); }
.toc a.on { font-weight: 700; }
.toc details > summary { cursor: pointer; list-style: none; }
.toc details > summary::-webkit-details-marker { display: none; }
.shelf .tip { margin: 1rem 0 0; font: 700 1.05rem/1.3 var(--f-head); color: var(--c-red); transform: rotate(-1.2deg); }

/* ── Текст статьи (разметка ТЗ) ────────────────── */
.body > * { max-width: var(--measure); }
.body > .tbl, .body > .tool { max-width: none; }
.body h2 { font-size: clamp(1.45rem, 1.15rem + 1vw, 1.8rem) !important; margin: 3rem 0 1rem; display: inline-block; padding-bottom: .15rem;
  background: linear-gradient(var(--c-red), var(--c-red)) no-repeat 0 100% / 2.6rem 4px; }
.body h2:first-child { margin-top: 0; }
.body h3 { font-size: 1.18rem !important; margin: 1.6rem 0 .5rem; }
.body p { margin: 0 0 1rem; }
.body p[style*="justify"] { text-align: left !important; }
.body sup { font-size: .72em; line-height: 0; }
.body sup a { text-decoration: none; font-weight: 800; color: var(--c-red); }
.body code { font-size: .9em; background: var(--panel); padding: .08em .35em; border-radius: 5px; }
.body pre { background: var(--ide); color: var(--ide-ink); padding: 1rem 1.2rem; border-radius: var(--r-2); overflow-x: auto; font-size: .92rem; line-height: 1.55; margin: 0 0 1.2rem; }
.body pre code { background: none; padding: 0; color: inherit; }
.text-blue { color: var(--c-blue); }
.b-500 { font-weight: 800; }
.mb-3 { margin-bottom: 1rem; }
.big-dash-list { list-style: none; padding: 0; margin: 0 0 1rem; display: grid; gap: .5rem; }
.big-dash-list li { position: relative; padding-left: 1.7rem; }
.big-dash-list li::before { content: ""; position: absolute; left: .2rem; top: .62em; width: .7rem; height: .7rem; border-radius: 3px; background: var(--c-green); transform: rotate(8deg); }
.custom-num-list { list-style: none; padding: 0; margin: 0 0 1rem; counter-reset: n; display: grid; gap: .7rem; }
.custom-num-list li { counter-increment: n; position: relative; padding-left: 2.8rem; }
.custom-num-list li::before { content: counter(n); position: absolute; left: 0; top: -.05em; width: 2rem; height: 2rem; display: grid; place-items: center; font: 700 1rem var(--f-head); color: var(--c-blue); border: 2.5px solid currentColor; border-radius: 50% 46% 52% 48%; }
.tbl { overflow-x: auto; margin: 0 0 1.4rem; border: 2px solid var(--line); border-radius: var(--r-2); background: var(--bg-2); }
.body table { border-collapse: collapse; width: 100%; min-width: 520px; font-size: .95rem; border: 0 !important; }
.body td, .body th { padding: .65rem .85rem !important; border: 0; border-bottom: 1.5px dashed var(--line); vertical-align: top; text-align: left; }
.body tr[style*="background"] { background: transparent !important; }
.body tr[style*="background"] td { font-family: var(--f-head); font-weight: 700; color: var(--c-blue); border-bottom: 2.5px solid var(--c-blue); }
.body tbody tr:last-child td { border-bottom: 0; }
.body blockquote { margin: 1.4rem 0; padding: 1.1rem 1.3rem 1rem; border-radius: 3px; color: var(--note-ink); box-shadow: 0 8px 18px -10px rgba(0,0,0,.35); position: relative; }
.body blockquote p { margin: 0; }
.body blockquote a { color: #1d4f9c; }
.body blockquote.myth { background: var(--note-y); transform: rotate(-.6deg); }
.body blockquote.note { background: var(--note-b); transform: rotate(.5deg); }
.body blockquote::before { display: block; font: 700 .95rem var(--f-head); margin-bottom: .25rem; }
.body blockquote.myth::before { content: "Миф"; color: #b23a2b; }
.body blockquote.note::before { content: "Не путать"; color: #1d4f9c; }

/* ── Кнопки, поля ──────────────────────────────── */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: .45rem; min-height: 44px; padding: .5rem 1.15rem; border-radius: var(--r-2); border: 2px solid var(--ink); background: var(--ink); color: var(--bg); font: 800 .95rem var(--f-body); cursor: pointer; text-decoration: none; }
.btn:hover { background: var(--c-blue); border-color: var(--c-blue); color: #fff; }
.btn.run { background: #2e9e5b; border-color: #2e9e5b; color: #fff; }
.btn.run:hover { background: #237a46; border-color: #237a46; }
.btn.line { background: transparent; color: inherit; border-color: currentColor; }
.btn.small { min-height: 36px; padding: .3rem .8rem; font-size: .88rem; }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.row { display: flex; flex-wrap: wrap; gap: .6rem; align-items: center; }
.ctl { display: grid; gap: .3rem; min-width: 0; }
.ctl label, .ctl .lbl { font-size: .85rem; opacity: .85; }
.ctl input[type="number"], .ctl input[type="text"], .ctl select { min-height: 42px; border-radius: var(--r-1); border: 1.5px solid var(--ide-3); background: var(--ide-2); color: var(--ide-ink); padding: .35rem .7rem; font: 600 1rem var(--f-body); min-width: 0; }
.verdict { padding: .6rem .9rem; border-radius: var(--r-1); font-weight: 800; }
.verdict.ok { background: var(--ok-bg); color: var(--ok); }
.verdict.bad { background: var(--bad-bg); color: var(--bad); }

/* ── Окно редактора (все инструменты) ──────────── */
.tool { background: var(--ide); color: var(--ide-ink); border-radius: var(--r-3); margin-block: .6rem 1rem; box-shadow: var(--shadow); overflow: hidden; border: 2px solid var(--ide-3); }
.tool-bar { display: flex; align-items: center; gap: .5rem; padding: .45rem .6rem .45rem .9rem; background: var(--ide-2); border-bottom: 1.5px solid var(--ide-3); flex-wrap: wrap; }
.tool-tab { font: 600 .85rem var(--f-code); color: var(--ide-ink); background: var(--ide); padding: .35rem .8rem; border-radius: 8px 8px 0 0; margin-bottom: -.5rem; border: 1.5px solid var(--ide-3); border-bottom-color: var(--ide); }
.tool-bar .sp { flex: 1; }
.tool-body { padding: 1rem; }
.tool a { color: #8fc1ff; }
.tool .muted { color: var(--ide-dim); }
.ide { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); min-height: 320px; }
@media (max-width: 860px) { .ide { grid-template-columns: minmax(0, 1fr); } }
.ide .ed { min-width: 0; border-right: 1.5px solid var(--ide-3); }
.ide .out { min-width: 0; display: grid; grid-template-rows: auto 1fr; background: #15181d; }
.out-h { display: flex; justify-content: space-between; align-items: center; padding: .4rem .8rem; font: 600 .78rem var(--f-code); color: var(--ide-dim); border-bottom: 1px solid var(--ide-3); }
.console { margin: 0; padding: .8rem; font: 400 .92rem/1.55 var(--f-code); white-space: pre-wrap; word-break: break-word; overflow: auto; max-height: 360px; color: #d8f5dd; }
.console .err { color: #ff9c9c; }
.console .hint { color: #f4d35e; display: block; margin-top: .4rem; font-family: var(--f-body); }
.console .inp { color: #8fc1ff; }
.input-row[hidden] { display: none; }
.input-row { display: flex; gap: .4rem; padding: .5rem .8rem; border-top: 1px solid var(--ide-3); }
.input-row input { flex: 1; min-width: 0; min-height: 38px; border-radius: 6px; border: 1.5px solid #8fc1ff; background: #0f1215; color: #fff; font: 500 .95rem var(--f-code); padding: 0 .6rem; }
.turtle { background: #fff; display: grid; place-items: center; min-height: 260px; border-top: 1px solid var(--ide-3); overflow: hidden; }
.turtle canvas { max-width: 100%; height: auto !important; }
.CodeMirror { height: 100%; min-height: 320px; font: 400 .95rem/1.55 var(--f-code); background: var(--ide) !important; color: var(--ide-ink) !important; }
.CodeMirror-gutters { background: var(--ide) !important; border-right: 1px solid var(--ide-3) !important; }
.CodeMirror-linenumber { color: #5c6773 !important; }
.CodeMirror-cursor { border-left: 2px solid #f4d35e !important; }
.CodeMirror-selected { background: #33404f !important; }
.tool .cm-keyword { color: #ff8fb1 !important; } .tool .cm-def, .tool .cm-variable-2 { color: #8fc1ff !important; } .tool .cm-string { color: #a8e0b8 !important; } .tool .cm-number { color: #f4d35e !important; }
.tool .cm-comment { color: #7d8a96 !important; font-style: italic; } .tool .cm-builtin { color: #ffb86b !important; } .tool .cm-operator { color: #e8ecef !important; } .tool .cm-property { color: #c3a6ff !important; }
textarea.code-fallback { width: 100%; min-height: 320px; background: var(--ide); color: var(--ide-ink); border: 0; padding: 1rem; font: .95rem/1.55 var(--f-code); resize: vertical; }

/* задачи */
.tasks-nav { display: flex; gap: .35rem; flex-wrap: wrap; }
.tasks-nav button { min-width: 2.4rem; min-height: 2.4rem; border-radius: 8px; border: 1.5px solid var(--ide-3); background: var(--ide); color: var(--ide-ink); font: 700 .9rem var(--f-code); cursor: pointer; }
.tasks-nav button[aria-current="true"] { border-color: #f4d35e; color: #f4d35e; }
.tasks-nav button.done { background: #1f4b36; border-color: #2e9e5b; }
.task-text { padding: 1rem 1rem .4rem; }
.task-text h3 { margin: 0 0 .4rem; font-size: 1.1rem; color: var(--ide-ink); }
.task-text p { margin: 0 0 .6rem; color: #cfd6dc; }
.tests { list-style: none; margin: 0; padding: 0; display: grid; gap: .3rem; font: .86rem var(--f-code); }
.tests li { padding: .35rem .6rem; border-radius: 6px; background: #15181d; }
.tests li.ok { color: #8fdcae; } .tests li.bad { color: #ff9c9c; }

/* квиз */
.quiz-q pre { background: #15181d; color: var(--ide-ink); padding: .9rem 1rem; border-radius: 10px; font: .95rem/1.5 var(--f-code); overflow-x: auto; margin: 0 0 .8rem; }
.opts { display: grid; gap: .45rem; }
.opts button { text-align: left; padding: .6rem .9rem; border-radius: 10px; border: 1.5px solid var(--ide-3); background: var(--ide-2); color: var(--ide-ink); font: 500 .95rem var(--f-code); cursor: pointer; white-space: pre-wrap; }
.opts button:hover { border-color: #8fc1ff; }
.opts button.ok { border-color: #2e9e5b; background: #1f4b36; }
.opts button.bad { border-color: #c43c3c; background: #4d2626; }

/* лабиринт */
.maze-wrap { display: grid; grid-template-columns: minmax(0, 1fr) minmax(260px, 340px); min-height: 420px; }
@media (max-width: 860px) { .maze-wrap { grid-template-columns: minmax(0, 1fr); } }
.blockly-area { min-height: 420px; min-width: 0; }
.maze-side { background: #15181d; padding: .8rem; display: grid; gap: .7rem; align-content: start; }
.maze-side canvas { width: 100%; height: auto; border-radius: 10px; background: #f6f7f2; }

/* двоичный конвертер, сортировка */
.bits { display: flex; flex-wrap: wrap; gap: .35rem; }
.bit { width: 3.1rem; display: grid; gap: .15rem; text-align: center; }
.bit button { height: 3.1rem; border-radius: 10px; border: 2px solid var(--ide-3); background: var(--ide-2); color: var(--ide-ink); font: 700 1.3rem var(--f-code); cursor: pointer; }
.bit button[aria-pressed="true"] { background: #f4d35e; color: #1c2026; border-color: #f4d35e; }
.bit span { font: .72rem var(--f-code); color: var(--ide-dim); }
.big-num { font: 700 clamp(2rem, 1.5rem + 2vw, 3rem) var(--f-code); }
.bars { display: flex; align-items: flex-end; gap: 4px; height: 220px; padding: .5rem; background: #15181d; border-radius: 10px; }
.bars i { flex: 1; background: #8fc1ff; border-radius: 4px 4px 0 0; transition: height .2s; min-width: 4px; }
.bars i.cmp { background: #f4d35e; } .bars i.sw { background: #ff8fb1; } .bars i.fin { background: #8fdcae; }
.stats { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: .5rem; }
.stat { background: #15181d; border-radius: 8px; padding: .5rem .6rem; }
.stat b { display: block; font: 700 1.25rem var(--f-code); }
.stat span { font-size: .75rem; color: var(--ide-dim); }
.check-list { list-style: none; padding: 0; margin: 0; display: grid; gap: .35rem; }
.check-list label { display: grid; grid-template-columns: 22px 1fr; gap: .6rem; padding: .5rem .6rem; border-radius: 8px; background: #15181d; cursor: pointer; }
.check-list input { width: 18px; height: 18px; margin-top: .2rem; accent-color: #2e9e5b; }
.meter { height: 10px; border-radius: 99px; background: #15181d; overflow: hidden; }
.meter i { display: block; height: 100%; width: 0; background: #2e9e5b; transition: width .3s; }
.calc-out { display: grid; gap: .35rem; }
.calc-out div { display: flex; justify-content: space-between; gap: 1rem; padding: .45rem .6rem; border-radius: 8px; background: #15181d; font-variant-numeric: tabular-nums; }
.two { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 1rem; }
@media (max-width: 760px) { .two { grid-template-columns: minmax(0, 1fr); } }
.chart { width: 100%; height: auto; }
.chart text { fill: var(--ide-dim); font: 12px var(--f-body); }
.chart .grid line { stroke: var(--ide-3); }

/* ── Главная ───────────────────────────────────── */
.hero { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr); gap: 2.5rem; align-items: center; padding-block: 3rem 2.5rem; }
@media (max-width: 920px) { .hero { grid-template-columns: minmax(0, 1fr); padding-block: 1.6rem; } }
.hero h1 { font-size: clamp(1.9rem, 1.2rem + 2.4vw, 3.1rem); hyphens: manual; overflow-wrap: normal; word-break: normal; margin: 0 0 1rem; }
.hero p { font-size: 1.15rem; color: var(--ink-2); max-width: 48ch; margin: 0 0 1.4rem; }
.demo-ide { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
@media (max-width: 560px) { .demo-ide { grid-template-columns: minmax(0, 1fr); } }
.demo-ide pre { margin: 0; padding: 1rem; font: .92rem/1.65 var(--f-code); color: var(--ide-ink); white-space: pre; overflow-x: auto; }
.demo-ide pre .ln { color: #5c6773; user-select: none; margin-right: .8rem; }
.demo-ide canvas { width: 100%; height: auto; background: #fff; display: block; }
.section { padding-block: 2.6rem; }
.section > h2 { font-size: clamp(1.6rem, 1.2rem + 1.4vw, 2.3rem); margin: 0 0 .4rem; }
.section > .sub { color: var(--ink-2); margin: 0 0 1.5rem; max-width: 62ch; }

/* блоки-карточки (как программные блоки с выемкой) */
.blocks { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 290px), 1fr)); gap: 1.3rem 1rem; }
.block { --k: var(--c-blue); position: relative; display: grid; gap: .3rem; align-content: start; padding: 1rem 1.1rem 1.05rem; text-decoration: none; color: var(--ink);
  background: var(--bg-2); border: 2px solid color-mix(in srgb, var(--k) 55%, var(--line)); border-left: 10px solid var(--k); border-radius: 8px 12px 12px 8px; transition: transform .12s; }
.block::before { content: ""; position: absolute; top: -2px; left: 18px; width: 30px; height: 9px; background: var(--bg); border: 2px solid color-mix(in srgb, var(--k) 55%, var(--line)); border-top: 0; border-radius: 0 0 8px 8px; }
.block:hover { transform: translateX(3px); color: var(--ink); }
.block i { font-style: normal; font-size: .78rem; font-weight: 800; color: var(--k); text-transform: none; }
.block b { font: 700 1.08rem/1.3 var(--f-head); }
.block span { color: var(--ink-2); font-size: .93rem; }
.k-start { --k: var(--k-start); } .k-scratch { --k: var(--k-scratch); } .k-python { --k: var(--k-python); } .k-praktikum { --k: var(--k-praktikum); }
.k-informatika { --k: var(--k-informatika); } .k-oshibki { --k: var(--k-oshibki); } .k-roditelyam { --k: var(--k-roditelyam); } .k-spravochnik { --k: var(--k-spravochnik); } .k-trenazhery { --k: var(--k-trenazhery); }
.steps-line { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1rem; counter-reset: s; }
@media (max-width: 900px) { .steps-line { grid-template-columns: minmax(0, 1fr); } }
.steps-line li { counter-increment: s; background: var(--bg-2); border: 2px dashed var(--line); border-radius: var(--r-2); padding: 1rem; }
.steps-line li::before { content: "шаг " counter(s); display: block; font: 700 .95rem var(--f-head); color: var(--c-red); }
.steps-line b { display: block; font: 700 1.1rem var(--f-head); margin: .2rem 0; }
.steps-line span { color: var(--ink-2); font-size: .95rem; }
.related { padding-block: 2rem; border-top: 2px dashed var(--line); }
.related h2 { font-size: 1.5rem; margin: 0 0 1rem; }
.hub-intro { max-width: var(--measure); color: var(--ink-2); }
.search-box { display: flex; gap: .5rem; flex-wrap: wrap; margin-bottom: 1.4rem; }
.search-box input { flex: 1 1 260px; min-height: 50px; border-radius: var(--r-2); border: 2px solid var(--line); background: var(--bg-2); color: var(--ink); padding: 0 1rem; font: 600 1.05rem var(--f-body); }
mark { background: var(--hl); color: inherit; padding: 0 2px; border-radius: 3px; }
.sitemap-group { margin-bottom: 2rem; }
.sitemap-group h2 { font-size: 1.35rem; margin: 0 0 .6rem; }
.sitemap-group ul { margin: 0; padding-left: 1.2rem; columns: 2; }
@media (max-width: 700px) { .sitemap-group ul { columns: 1; } }
.err-404 { padding-block: 4rem; max-width: 640px; }
.err-404 .num { font: 700 clamp(5rem, 3rem + 10vw, 9rem)/1 var(--f-code); color: var(--c-red); }

/* ── Подвал ────────────────────────────────────── */
.foot { margin-top: 2rem; border-top: 2px solid var(--line); background: var(--bg-2); padding-block: 2rem; font-size: .93rem; color: var(--ink-2); }
.foot .cols { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 1.5rem; }
@media (max-width: 760px) { .foot .cols { grid-template-columns: minmax(0, 1fr); } }
.foot h3 { font-size: 1rem; margin: 0 0 .5rem; color: var(--ink); }
.foot ul { list-style: none; margin: 0; padding: 0; display: grid; gap: .3rem; }
.foot a { color: var(--ink-2); }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; animation: none !important; } }