/* ============================================================
   „Zbuduj własny LLM" — design system
   Theme: "terminal at dusk" + token-chip motif.
   System fonts only (offline-safe). Dark by default.
   ============================================================ */

:root {
  /* palette */
  --bg: #14161c;          /* deep slate-ink */
  --bg-raised: #1b1e26;   /* cards, code blocks */
  --bg-inset: #101217;    /* wells, terminal output */
  --line: #2a2e3a;        /* hairlines */
  --ink: #e9e5db;         /* warm off-white body text */
  --ink-dim: #a5a2ab;     /* secondary text */
  --ink-faint: #6d6b75;   /* captions, labels */
  --amber: #e4b558;       /* primary accent: attention heat */
  --teal: #7fb8a4;        /* secondary accent: code, links */
  --rose: #d98a8a;
  --lilac: #a99ae0;
  --sage: #9ab87f;

  /* token tints (translucent chips, tokenizer-visualizer style) */
  --tok-1: rgba(169, 154, 224, 0.16);
  --tok-2: rgba(127, 184, 164, 0.16);
  --tok-3: rgba(228, 181, 88, 0.14);
  --tok-4: rgba(217, 138, 138, 0.14);
  --tok-5: rgba(154, 184, 127, 0.14);
  --tok-b-1: rgba(169, 154, 224, 0.45);
  --tok-b-2: rgba(127, 184, 164, 0.45);
  --tok-b-3: rgba(228, 181, 88, 0.40);
  --tok-b-4: rgba(217, 138, 138, 0.40);
  --tok-b-5: rgba(154, 184, 127, 0.40);

  /* type */
  --serif: "Iowan Old Style", "Palatino", "Book Antiqua", Georgia, serif;
  --sans: "Seravek", "Avenir Next", -apple-system, "Segoe UI", sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, "Cascadia Code", monospace;

  /* stable rem (not ch): ch resolves per-element font-size and desynced
     section width vs marginalia offset */
  --content: 46rem;
  --margin-rail: 19rem;
  --radius: 6px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* --------------- i18n: PL/EN visibility --------------- */
html[data-lang="pl"] .lang-en { display: none !important; }
html[data-lang="en"] .lang-pl { display: none !important; }

/* --------------- header --------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; gap: 1rem;
  padding: 0.55rem 1.25rem;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .brand {
  font-family: var(--mono); font-size: 0.85rem; letter-spacing: 0.02em;
  color: var(--ink); text-decoration: none; white-space: nowrap;
}
.site-header .brand .tok { padding: 0.1rem 0.3rem; border-radius: 4px; }
.site-header .brand .tok:nth-child(1) { background: var(--tok-1); }
.site-header .brand .tok:nth-child(2) { background: var(--tok-2); }
.site-header .brand .tok:nth-child(3) { background: var(--tok-3); }
.site-header .brand .tok:nth-child(4) { background: var(--tok-4); }

/* strip of 20 module chips in the header */
.module-strip { display: flex; gap: 3px; flex: 1; min-width: 0; overflow: hidden; }
.module-strip a {
  width: 14px; height: 14px; border-radius: 3px; flex: none;
  background: var(--bg-raised); border: 1px solid var(--line);
  text-decoration: none; position: relative;
}
.module-strip a.done { background: var(--tok-2); border-color: var(--tok-b-2); }
.module-strip a.current { background: var(--tok-3); border-color: var(--amber); }
.module-strip a:hover::after {
  content: attr(data-title); position: absolute; top: 20px; left: 50%;
  transform: translateX(-50%); white-space: nowrap;
  background: var(--bg-inset); border: 1px solid var(--line);
  padding: 0.2rem 0.5rem; border-radius: 4px;
  font: 0.72rem var(--mono); color: var(--ink-dim); z-index: 60;
}

/* PL/EN toggle: two tokens, active one "sampled" */
.lang-toggle {
  display: flex; gap: 2px; font-family: var(--mono); font-size: 0.8rem;
  border: 1px solid var(--line); border-radius: 6px; padding: 2px;
  background: var(--bg-inset);
}
.lang-toggle button {
  border: 0; background: transparent; color: var(--ink-faint);
  font: inherit; padding: 0.15rem 0.55rem; border-radius: 4px; cursor: pointer;
}
.lang-toggle button[aria-pressed="true"] { background: var(--tok-3); color: var(--amber); }
.lang-toggle button:focus-visible,
a:focus-visible, button:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--amber); outline-offset: 2px;
}

/* --------------- page layout --------------- */
.page {
  max-width: calc(var(--content) + var(--margin-rail) + 6rem);
  margin: 0 auto; padding: 2.5rem 1.5rem 6rem;
}
.module-body section { position: relative; max-width: var(--content); }

/* module hero */
.module-hero { max-width: var(--content); margin-bottom: 3rem; }
.module-hero .token-id {
  font-family: var(--mono); font-size: 0.8rem; color: var(--ink-faint);
}
.module-hero .token-id b { color: var(--amber); font-weight: 600; }
.module-hero h1 {
  font-family: var(--serif); font-weight: 500; letter-spacing: -0.01em;
  font-size: clamp(1.9rem, 4vw, 2.7rem); line-height: 1.15; margin: 0.35rem 0 0.6rem;
}
.module-hero .lede { color: var(--ink-dim); font-size: 1.12rem; max-width: 60ch; }

/* tokenized heading effect: wrap words in .tok spans */
h1 .tok, .tokenized .tok {
  border-radius: 5px; padding: 0 0.18em;
  box-decoration-break: clone; -webkit-box-decoration-break: clone;
}
h1 .tok:nth-child(5n+1), .tokenized .tok:nth-child(5n+1) { background: var(--tok-1); }
h1 .tok:nth-child(5n+2), .tokenized .tok:nth-child(5n+2) { background: var(--tok-2); }
h1 .tok:nth-child(5n+3), .tokenized .tok:nth-child(5n+3) { background: var(--tok-3); }
h1 .tok:nth-child(5n+4), .tokenized .tok:nth-child(5n+4) { background: var(--tok-4); }
h1 .tok:nth-child(5n+5), .tokenized .tok:nth-child(5n+5) { background: var(--tok-5); }

/* headings */
h2 {
  font-family: var(--serif); font-weight: 500; font-size: 1.65rem;
  margin: 3rem 0 0.8rem; line-height: 1.2;
}
h2 .sec-no { font-family: var(--mono); font-size: 0.8rem; color: var(--amber); display: block; margin-bottom: 0.3rem; }
h3 { font-family: var(--sans); font-weight: 600; font-size: 1.15rem; margin: 2rem 0 0.5rem; }
p { margin: 0.8rem 0; }
a { color: var(--teal); text-decoration-color: color-mix(in srgb, var(--teal) 40%, transparent); }
a:hover { text-decoration-color: var(--teal); }
strong { color: #fff; font-weight: 600; }
ul, ol { padding-left: 1.4rem; }
li { margin: 0.35rem 0; }
hr { border: 0; border-top: 1px solid var(--line); margin: 3rem 0; }

/* inline code + kbd */
code {
  font-family: var(--mono); font-size: 0.88em;
  background: var(--bg-raised); border: 1px solid var(--line);
  border-radius: 4px; padding: 0.08em 0.35em; color: #d7d3e3;
}
kbd {
  font-family: var(--mono); font-size: 0.85em; border: 1px solid var(--line);
  border-bottom-width: 2px; border-radius: 4px; padding: 0.05em 0.4em;
  background: var(--bg-inset);
}

/* --------------- code blocks --------------- */
.code-block {
  position: relative; margin: 1.4rem 0; max-width: var(--content);
  background: var(--bg-raised); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
}
.code-block .code-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.4rem 0.9rem; border-bottom: 1px solid var(--line);
  font: 0.75rem var(--mono); color: var(--ink-faint);
}
.code-block pre {
  margin: 0; padding: 0.9rem 1rem; overflow-x: auto;
  font: 0.85rem/1.55 var(--mono); color: #dcd9e6;
}
.code-block pre code { background: none; border: 0; padding: 0; font-size: inherit; }
.code-block .code-head .code-file {
  color: var(--ink-dim); text-decoration: none; border-bottom: 1px dotted var(--line);
}
.code-block .code-head .code-file:hover { color: var(--teal); border-bottom-color: var(--teal); }
.code-file-arrow { opacity: 0.7; }
.code-tag {
  margin-left: 0.55rem; padding: 0.05rem 0.45rem; border-radius: 999px;
  border: 1px solid var(--line); background: var(--bg-inset); color: var(--ink-faint);
  font: 0.66rem var(--mono); letter-spacing: 0.04em; text-transform: uppercase; cursor: help;
}
/* keep filename + tag on the left, copy button on the right */
.code-block .code-head { gap: 0.4rem; }
.code-block .code-head .copy-btn { margin-left: auto; }
.copy-btn {
  border: 1px solid var(--line); background: var(--bg-inset); color: var(--ink-dim);
  font: 0.72rem var(--mono); padding: 0.15rem 0.6rem; border-radius: 4px; cursor: pointer;
}
.copy-btn:hover { color: var(--ink); border-color: var(--ink-faint); }

/* pobranie całego kodu kursu (.zip) */
.dl-code {
  display: inline-flex; align-items: center; gap: 0.5rem;
  margin-top: 0.9rem; padding: 0.5rem 1rem; border-radius: var(--radius);
  border: 1px solid var(--amber); background: var(--bg-inset);
  color: var(--amber); text-decoration: none;
  font: 0.85rem var(--mono);
}
.dl-code:hover { background: var(--amber); color: var(--bg); }
.dl-code .dl-ico { font-size: 1.05em; }

/* hand-rolled syntax highlight classes (course.js) */
.tk-kw { color: var(--lilac); }
.tk-str { color: var(--sage); }
.tk-com { color: var(--ink-faint); font-style: italic; }
.tk-num { color: var(--amber); }
.tk-fn  { color: var(--teal); }

/* terminal output block */
.term {
  margin: 1.4rem 0; max-width: var(--content);
  background: var(--bg-inset); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 0.9rem 1rem;
  font: 0.85rem/1.55 var(--mono); color: var(--ink-dim);
  overflow-x: auto; white-space: pre;
}
.term .prompt { color: var(--teal); }

/* --------------- marginalia (nowinki, notes) --------------- */
.marginalia {
  position: absolute; left: calc(var(--content) + 3rem); width: var(--margin-rail);
  font-size: 0.85rem; line-height: 1.5; color: var(--ink-dim);
  border-left: 2px solid var(--tok-b-3); padding-left: 0.9rem;
}
.marginalia .tag {
  display: inline-block; font: 600 0.68rem var(--mono); letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--amber); margin-bottom: 0.3rem;
}
.marginalia.note { border-color: var(--tok-b-1); }
.marginalia.note .tag { color: var(--lilac); }
@media (max-width: 1180px) {
  .marginalia {
    position: static; width: auto; margin: 1.2rem 0;
    background: var(--bg-raised); border: 1px solid var(--line);
    border-left: 2px solid var(--tok-b-3); border-radius: var(--radius);
    padding: 0.8rem 1rem;
  }
}

/* --------------- boxes --------------- */
.box {
  margin: 1.6rem 0; max-width: var(--content);
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1rem 1.2rem; background: var(--bg-raised);
}
.box .box-title {
  font: 600 0.75rem var(--mono); letter-spacing: 0.08em; text-transform: uppercase;
  margin-bottom: 0.4rem;
}
.box.exercise { border-left: 3px solid var(--teal); }
.box.exercise .box-title { color: var(--teal); }
.box.warning { border-left: 3px solid var(--rose); }
.box.warning .box-title { color: var(--rose); }
.box.data { border-left: 3px solid var(--sage); }
.box.data .box-title { color: var(--sage); }
.box.goal { border-left: 3px solid var(--amber); }
.box.goal .box-title { color: var(--amber); }

/* file reference chip */
.file-chip {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font: 0.8rem var(--mono); color: var(--teal);
  background: var(--bg-inset); border: 1px solid var(--line);
  border-radius: 5px; padding: 0.2rem 0.6rem; margin: 0.15rem 0.2rem 0.15rem 0;
}

/* math (hand-rolled, no external libs) */
.math {
  font-family: var(--serif); font-style: italic; font-size: 1.05em;
  color: #f0ecdf;
}
.math-block {
  margin: 1.4rem 0; padding: 1rem 1.4rem; max-width: var(--content);
  text-align: center; font-size: 1.15rem;
  background: var(--bg-inset); border: 1px solid var(--line); border-radius: var(--radius);
}
.math sup, .math sub, .math-block sup, .math-block sub { font-size: 0.72em; }
.frac { display: inline-flex; flex-direction: column; vertical-align: middle; text-align: center; margin: 0 0.15em; }
.frac > span { display: block; padding: 0 0.25em; }
.frac > span:first-child { border-bottom: 1px solid currentColor; }

/* tables */
table { border-collapse: collapse; margin: 1.4rem 0; font-size: 0.92rem; max-width: var(--content); display: block; overflow-x: auto; }
th, td { border: 1px solid var(--line); padding: 0.45rem 0.8rem; text-align: left; vertical-align: top; }
th { background: var(--bg-raised); font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.04em; color: var(--ink-dim); }
tbody tr:hover { background: rgba(255,255,255,0.02); }

/* --------------- interactive widgets --------------- */
.widget {
  margin: 1.8rem 0; max-width: var(--content);
  border: 1px solid var(--tok-b-2); border-radius: var(--radius);
  background: var(--bg-inset); padding: 1rem 1.2rem;
}
.widget .widget-title {
  font: 600 0.75rem var(--mono); letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--teal); margin-bottom: 0.6rem;
}
.widget canvas, .widget svg { max-width: 100%; display: block; }
.widget .controls { display: flex; flex-wrap: wrap; gap: 0.8rem 1.4rem; align-items: center; margin-top: 0.8rem; }
.widget label { font: 0.8rem var(--mono); color: var(--ink-dim); display: flex; align-items: center; gap: 0.5rem; }
.widget input[type="range"] { accent-color: var(--amber); }
.widget input[type="text"], .widget textarea, .widget select {
  background: var(--bg-raised); color: var(--ink); border: 1px solid var(--line);
  border-radius: 4px; font: 0.85rem var(--mono); padding: 0.35rem 0.6rem;
}
.widget button, .btn {
  background: var(--tok-3); color: var(--amber); border: 1px solid var(--tok-b-3);
  font: 600 0.82rem var(--mono); padding: 0.35rem 0.9rem; border-radius: 5px; cursor: pointer;
}
.widget button:hover, .btn:hover { filter: brightness(1.15); }
.widget .readout { font: 0.85rem var(--mono); color: var(--amber); }

/* token chips inside widgets (tokenizer demos etc.) */
.tok-chip {
  display: inline-block; font: 0.85rem var(--mono); border-radius: 4px;
  padding: 0.1rem 0.3rem; margin: 2px 1px; white-space: pre;
}
.tok-chip.c1 { background: var(--tok-1); box-shadow: inset 0 0 0 1px var(--tok-b-1); }
.tok-chip.c2 { background: var(--tok-2); box-shadow: inset 0 0 0 1px var(--tok-b-2); }
.tok-chip.c3 { background: var(--tok-3); box-shadow: inset 0 0 0 1px var(--tok-b-3); }
.tok-chip.c4 { background: var(--tok-4); box-shadow: inset 0 0 0 1px var(--tok-b-4); }
.tok-chip.c5 { background: var(--tok-5); box-shadow: inset 0 0 0 1px var(--tok-b-5); }

/* --------------- next-token navigation --------------- */
.next-token-nav {
  display: flex; justify-content: space-between; gap: 1rem;
  margin-top: 4rem; padding-top: 1.5rem; border-top: 1px solid var(--line);
  max-width: var(--content);
}
.next-token-nav a {
  display: block; text-decoration: none; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 0.7rem 1rem; min-width: 0; flex: 1;
  background: var(--bg-raised);
}
.next-token-nav a:hover { border-color: var(--tok-b-3); }
.next-token-nav .dir { font: 0.7rem var(--mono); color: var(--ink-faint); display: block; }
.next-token-nav .prob { color: var(--amber); }
.next-token-nav .t { color: var(--ink); font-size: 0.95rem; }
.next-token-nav a.next { text-align: right; }

/* mark-complete control */
.complete-row { margin-top: 2.5rem; max-width: var(--content); display: flex; justify-content: center; }
.complete-btn {
  background: var(--bg-raised); border: 1px solid var(--tok-b-2); color: var(--teal);
  font: 600 0.85rem var(--mono); border-radius: 6px; padding: 0.5rem 1.2rem; cursor: pointer;
}
.complete-btn.done { background: var(--tok-2); }

/* --------------- index page --------------- */
.course-hero { text-align: left; margin: 3rem 0 3.5rem; max-width: 64ch; }
.course-hero h1 {
  font-family: var(--serif); font-weight: 500; font-size: clamp(2.2rem, 5vw, 3.4rem);
  line-height: 1.12; margin: 0.5rem 0 1rem; letter-spacing: -0.01em;
}
.course-hero .lede { font-size: 1.15rem; color: var(--ink-dim); max-width: 58ch; }
.part-label {
  font: 600 0.75rem var(--mono); letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--amber); margin: 2.8rem 0 0.9rem; display: flex; align-items: center; gap: 0.8rem;
}
.part-label::after { content: ""; height: 1px; background: var(--line); flex: 1; }
.module-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 0.8rem; }
.module-card {
  display: block; text-decoration: none; color: var(--ink);
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--bg-raised); padding: 0.9rem 1rem; position: relative;
}
.module-card:hover { border-color: var(--tok-b-3); transform: translateY(-1px); transition: all 120ms ease; }
.module-card .mid { font: 0.72rem var(--mono); color: var(--ink-faint); }
.module-card .mid b { color: var(--amber); font-weight: 600; }
.module-card .mtitle { font-weight: 600; margin: 0.25rem 0 0.2rem; }
.module-card .msub { font-size: 0.85rem; color: var(--ink-dim); }
.module-card .badges { margin-top: 0.5rem; display: flex; gap: 0.4rem; flex-wrap: wrap; }
.badge { font: 0.68rem var(--mono); border-radius: 4px; padding: 0.08rem 0.45rem; }
.badge.cpu { background: var(--tok-2); color: var(--teal); }
.badge.mps { background: var(--tok-3); color: var(--amber); }
.badge.time { background: var(--tok-1); color: var(--lilac); }
.module-card.done::after {
  content: "✓"; position: absolute; top: 0.7rem; right: 0.8rem;
  color: var(--teal); font-weight: 700;
}

/* footer */
.site-footer {
  margin-top: 5rem; padding: 1.5rem; border-top: 1px solid var(--line);
  font: 0.8rem var(--mono); color: var(--ink-faint); text-align: center;
}

/* scroll reveal */
.reveal { opacity: 0; transform: translateY(10px); transition: opacity 500ms ease, transform 500ms ease; }
.reveal.shown { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; } }

@media (max-width: 700px) {
  .page { padding: 1.5rem 1rem 4rem; }
  .module-strip { display: none; }
  body { font-size: 1rem; }
}

/* --------------- quiz („Sprawdź się") --------------- */
.quiz {
  margin: 2.5rem 0 1rem; max-width: var(--content);
  border: 1px solid var(--tok-b-1); border-radius: var(--radius);
  background: var(--bg-inset); padding: 1.1rem 1.3rem;
}
.quiz .quiz-head {
  font: 600 0.75rem var(--mono); letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--lilac); margin-bottom: 0.2rem;
  display: flex; justify-content: space-between; align-items: baseline; gap: 1rem;
}
.quiz .quiz-score { color: var(--ink-dim); text-transform: none; letter-spacing: 0; }
.quiz-q { margin: 1.2rem 0; padding-top: 1rem; border-top: 1px dashed var(--line); }
.quiz-q:first-of-type { border-top: 0; }
.quiz-q .qtext { font-weight: 600; margin-bottom: 0.6rem; }
.quiz-q .qno { font: 0.75rem var(--mono); color: var(--ink-faint); margin-right: 0.5rem; }
.quiz-opts { display: grid; gap: 0.4rem; }
.quiz-opts button {
  text-align: left; font: 0.92rem var(--sans); line-height: 1.45;
  background: var(--bg-raised); color: var(--ink); cursor: pointer;
  border: 1px solid var(--line); border-radius: 5px; padding: 0.5rem 0.8rem;
}
.quiz-opts button:hover:not(:disabled) { border-color: var(--tok-b-1); }
.quiz-opts button:disabled { cursor: default; opacity: 0.75; }
.quiz-opts button.good { border-color: var(--sage); background: var(--tok-5); opacity: 1; color: #fff; }
.quiz-opts button.bad { border-color: var(--rose); background: var(--tok-4); opacity: 1; }
.quiz-expl {
  margin: 0.6rem 0 0; font-size: 0.9rem; color: var(--ink-dim);
  border-left: 2px solid var(--tok-b-2); padding: 0.2rem 0 0.2rem 0.8rem;
}
.quiz-summary {
  margin-top: 1.2rem; padding-top: 1rem; border-top: 1px solid var(--line);
  display: flex; align-items: center; gap: 1rem; flex-wrap: wrap;
  font: 0.9rem var(--mono);
}
.quiz-summary .pass { color: var(--sage); }
.quiz-summary .fail { color: var(--rose); }

/* "predict before you run" boxes */
details.predict {
  margin: 1.2rem 0; max-width: var(--content);
  border: 1px dashed var(--tok-b-1); border-radius: var(--radius);
  background: var(--bg-inset); padding: 0.6rem 1rem;
}
details.predict summary {
  cursor: pointer; font-weight: 600; color: var(--lilac);
  font-size: 0.95rem; list-style-position: outside;
}
details.predict summary::marker { color: var(--lilac); }
details.predict[open] summary { margin-bottom: 0.4rem; }
details.predict p { font-size: 0.92rem; color: var(--ink-dim); }

/* per-module mini table of contents */
.page-toc {
  max-width: var(--content); margin: -1.5rem 0 2rem;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--bg-raised); padding: 0.5rem 1rem;
  font-size: 0.88rem;
}
.page-toc summary {
  cursor: pointer; font: 600 0.72rem var(--mono); letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--ink-faint); padding: 0.2rem 0;
}
.page-toc ol { margin: 0.4rem 0 0.4rem; padding-left: 1.2rem; }
.page-toc a { color: var(--ink-dim); text-decoration: none; }
.page-toc a:hover { color: var(--teal); }
.page-toc .sec-no-toc { font: 0.75rem var(--mono); color: var(--amber); margin-right: 0.4rem; }

/* --------------- search (Ctrl+K) --------------- */
.search-btn {
  display: flex; align-items: center; gap: 0.45rem;
  border: 1px solid var(--line); border-radius: 6px; background: var(--bg-inset);
  color: var(--ink-faint); font: 0.8rem var(--mono); padding: 0.25rem 0.6rem; cursor: pointer;
  white-space: nowrap;
}
.search-btn:hover { color: var(--ink-dim); border-color: var(--ink-faint); }
.search-btn kbd { border: 1px solid var(--line); font-size: 0.7rem; padding: 0 0.3em; background: var(--bg-raised); }
.search-overlay {
  position: fixed; inset: 0; z-index: 100; display: none;
  background: rgba(10, 11, 15, 0.72); backdrop-filter: blur(3px);
  padding: 10vh 1rem 0;
}
.search-overlay.open { display: block; }
.search-panel {
  max-width: 44rem; margin: 0 auto; background: var(--bg-raised);
  border: 1px solid var(--tok-b-1); border-radius: 10px; overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.search-panel input {
  width: 100%; border: 0; outline: 0; background: var(--bg-inset); color: var(--ink);
  font: 1rem var(--sans); padding: 0.9rem 1.1rem; border-bottom: 1px solid var(--line);
}
.search-results { max-height: 55vh; overflow-y: auto; }
.search-results .hit {
  display: block; padding: 0.7rem 1.1rem; text-decoration: none; color: var(--ink);
  border-bottom: 1px solid var(--line);
}
.search-results .hit:hover, .search-results .hit.sel { background: var(--bg-inset); }
.search-results .hit .where { font: 0.72rem var(--mono); color: var(--amber); }
.search-results .hit .snip { font-size: 0.85rem; color: var(--ink-dim); display: block; margin-top: 0.15rem; }
.search-results .none { padding: 1rem 1.1rem; color: var(--ink-faint); font: 0.85rem var(--mono); }
.search-results mark { background: var(--tok-3); color: var(--amber); border-radius: 3px; padding: 0 0.1em; }

/* --------------- index extras --------------- */
.progress-wrap { max-width: 64ch; margin: 0 0 1rem; }
.progress-bar {
  height: 10px; border-radius: 6px; background: var(--bg-raised);
  border: 1px solid var(--line); overflow: hidden;
}
.progress-bar > div { height: 100%; background: linear-gradient(90deg, var(--teal), var(--amber)); border-radius: 6px; }
.progress-meta { font: 0.78rem var(--mono); color: var(--ink-dim); margin-top: 0.35rem; display: flex; gap: 1.2rem; flex-wrap: wrap; }
.resume-banner {
  display: inline-flex; align-items: center; gap: 0.7rem; margin: 0.6rem 0 0;
  border: 1px solid var(--tok-b-2); border-radius: 6px; background: var(--bg-raised);
  padding: 0.45rem 0.9rem; text-decoration: none; color: var(--teal);
  font: 0.85rem var(--mono);
}
.resume-banner:hover { border-color: var(--teal); }
.hub-links { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: 0.8rem; margin: 1rem 0 0; }
.hub-card {
  display: block; text-decoration: none; color: var(--ink);
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--bg-raised); padding: 0.75rem 0.95rem;
}
.hub-card:hover { border-color: var(--tok-b-1); }
.hub-card .h { font-weight: 600; font-size: 0.95rem; }
.hub-card .s { font-size: 0.8rem; color: var(--ink-dim); margin-top: 0.15rem; }
.hub-card .due { color: var(--amber); font: 0.78rem var(--mono); }

/* mobile module jump */
.module-select { display: none; }
@media (max-width: 700px) {
  .module-select {
    display: block; flex: 1; min-width: 0;
    background: var(--bg-inset); color: var(--ink-dim); border: 1px solid var(--line);
    border-radius: 6px; font: 0.8rem var(--mono); padding: 0.3rem 0.4rem;
  }
}

/* --------------- review (spaced repetition) page --------------- */
.sr-stage { max-width: var(--content); margin: 1.5rem 0; }
.sr-card {
  border: 1px solid var(--tok-b-1); border-radius: 10px; background: var(--bg-raised);
  padding: 1.4rem 1.6rem; min-height: 12rem;
  display: flex; flex-direction: column; gap: 0.8rem;
}
.sr-card .src { font: 0.72rem var(--mono); color: var(--ink-faint); }
.sr-card .q { font-weight: 600; font-size: 1.1rem; }
.sr-card .ans { border-top: 1px dashed var(--line); padding-top: 0.8rem; }
.sr-card .ans .correct { color: var(--sage); font-weight: 600; }
.sr-actions { display: flex; gap: 0.8rem; margin-top: 1rem; flex-wrap: wrap; }
.sr-actions .btn.again { background: var(--tok-4); color: var(--rose); border-color: var(--tok-b-4); }
.sr-actions .btn.goodb { background: var(--tok-5); color: var(--sage); border-color: var(--tok-b-5); }
.sr-empty { color: var(--ink-dim); font-size: 1rem; max-width: 60ch; }
.sr-meta { font: 0.78rem var(--mono); color: var(--ink-faint); margin-top: 0.8rem; }

/* --------------- glossary page --------------- */
.gloss-filter { margin: 1rem 0 1.5rem; max-width: var(--content); }
.gloss-filter input {
  width: 100%; background: var(--bg-raised); border: 1px solid var(--line);
  border-radius: 6px; color: var(--ink); font: 1rem var(--sans); padding: 0.6rem 1rem;
}
.gloss-entry {
  max-width: var(--content); padding: 0.8rem 0; border-bottom: 1px solid var(--line);
}
.gloss-entry dt { font-weight: 600; font-size: 1.02rem; }
.gloss-entry dt .mref { font: 0.72rem var(--mono); color: var(--amber); margin-left: 0.6rem; text-decoration: none; }
.gloss-entry dd { margin: 0.25rem 0 0; color: var(--ink-dim); font-size: 0.94rem; }
.gloss-letter {
  font: 600 0.8rem var(--mono); color: var(--amber); text-transform: uppercase;
  margin: 1.6rem 0 0.2rem;
}

/* --------------- certificate page --------------- */
.cert-wrap { max-width: var(--content); }
.cert-canvas-box { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; margin: 1.2rem 0; }
.cert-canvas-box canvas { width: 100%; display: block; }
.cert-controls { display: flex; gap: 0.8rem; flex-wrap: wrap; align-items: center; }
.cert-controls input {
  background: var(--bg-raised); border: 1px solid var(--line); border-radius: 6px;
  color: var(--ink); font: 1rem var(--sans); padding: 0.5rem 0.9rem; min-width: 16rem;
}
.cert-lock { color: var(--ink-dim); }

/* print: light, ink-friendly */
@media print {
  :root { --bg: #fff; --bg-raised: #f6f5f2; --bg-inset: #f6f5f2; --ink: #1a1a1a; --ink-dim: #444; --line: #ccc; }
  .site-header, .next-token-nav, .complete-row, .copy-btn, .quiz, .search-overlay, .page-toc, .module-select { display: none; }
}