/* Harnessing Claude Code — site stylesheet
   Design system: dotted paper, hard offset shadows, a pixel display face, and
   one accent colour. The palette is "Void & Violet" — a violet accent on cool
   neutrals — chosen to replace the one this repo was originally reverse-
   engineered against, so the site is not a colour-for-colour copy.
   Single source of truth, no preprocessor. */

:root {
  /* fonts */
  --font-display: 'VT323', ui-monospace, 'JetBrains Mono', monospace;
  --font-body:    'Source Serif 4', 'Source Serif Pro', 'Iowan Old Style', Georgia, serif;
  --font-mono:    'JetBrains Mono', ui-monospace, 'Consolas', monospace;
  --font-heading: var(--font-display);

  /* light theme — Void & Violet.
     The tokens below replace a palette that was copied from the reference site
     this repo was reverse-engineered against. The structure (dotted paper,
     hard shadows, VT323 display face) is unchanged; only the colours moved. */
  --bg:               #f6f4fb;
  --bg-surface:       #eae5f7;
  --bg-surface-hover: #ded6f2;
  --ink:              #17122a;
  --ink-soft:         #574d78;
  --ink-mute:         #6a6089;
  --rule:             #17122a;
  --rule-soft:        rgba(23, 18, 42, 0.16);
  --paper-rule:       rgba(23, 18, 42, 0.07);
  --blueprint:        #6d28d9;
  --blueprint-tint:        rgba(109, 40, 217, 0.09);
  --blueprint-tint-strong: rgba(109, 40, 217, 0.20);
  --status-complete:      #6d28d9;
  --status-in-progress:   #574d78;
  --status-planned:       #c3bcd8;
  --warn:           #8a6d0b;
  --code-bg:        #e9e4f6;
  --modal-bg:       #f6f4fb;
  --overlay-bg:     rgba(23, 18, 42, 0.55);
  --header-bg:      rgba(246, 244, 251, 0.94);
  --accent-hover:   #5b21b6;
  /* Text on a filled accent. White works on the light-mode violet; on the
     dark-mode violet (a light colour) it does not — 2.72:1 — so dark mode
     flips it to near-black. */
  --on-accent:      #ffffff;

  /* semantic aliases */
  --text:        var(--ink);
  --text-muted:  var(--ink-soft);
  --border:      var(--rule-soft);
  --accent:      var(--blueprint);
  --secondary:   var(--blueprint);
  --complete:    var(--status-complete);
  --planned:     var(--status-planned);
  --dot-color:   var(--paper-rule);
  --shadow-color: var(--ink);
  --shadow-hard:    3px 3px 0 var(--ink);
  --shadow-hard-lg: 5px 5px 0 var(--ink);

  /* motion */
  --motion-press:    160ms;
  --motion-feedback: 180ms;
  --motion-enter:    220ms;
  --motion-drawer:   250ms;
  --ease-out:    cubic-bezier(0.23, 1, 0.32, 1);
  --ease-in-out: cubic-bezier(0.77, 0, 0.175, 1);
  --ease-drawer: cubic-bezier(0.32, 0.72, 0, 1);

  --header-h: 64px;
  --toc-w: 300px;
  --read-w: 46rem;
}

[data-theme="dark"] {
  --bg:               #0e0b16;
  --bg-surface:       #181229;
  --bg-surface-hover: #211a38;
  --ink:              #e7e2f6;
  --ink-soft:         #a69dc7;
  --ink-mute:         #877eab;
  --rule:             #e7e2f6;
  --rule-soft:        rgba(231, 226, 246, 0.20);
  --paper-rule:       rgba(231, 226, 246, 0.07);
  --blueprint:        #a78bfa;
  --blueprint-tint:        rgba(167, 139, 250, 0.14);
  --blueprint-tint-strong: rgba(167, 139, 250, 0.26);
  --status-complete:      #a78bfa;
  --status-in-progress:   #a69dc7;
  --status-planned:       #4a4168;
  --warn:           #d9b34a;
  --code-bg:        #1c1533;
  --modal-bg:       #130f22;
  --overlay-bg:     rgba(14, 11, 22, 0.78);
  --header-bg:      rgba(14, 11, 22, 0.94);
  --accent-hover:   #c4b0ff;
  --on-accent:      #140f24;
}

* { box-sizing: border-box; }

html { font-size: 17px; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.62;
  color: var(--ink);
  background:
    radial-gradient(circle at 1px 1px, var(--paper-rule) 1px, transparent 0) 0 0 / 16px 16px,
    var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  letter-spacing: 0.02em;
  margin: 0 0 0.6em;
  line-height: 1.15;
}

h1 { font-size: 2.4rem; color: var(--blueprint); text-transform: uppercase; }
h2 { font-size: 1.6rem; }
h3 { font-size: 1.2rem; }

p { margin: 0 0 1em; }

a { color: var(--blueprint); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }

code, pre {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: var(--code-bg);
  border-radius: 2px;
}

code { padding: 0.1em 0.35em; }
pre {
  padding: 0.9rem 1.1rem;
  border-left: 2.5px solid var(--rule-soft);
  overflow-x: auto;
}
pre code { background: none; padding: 0; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 32px; }

/* ── skip link ───────────────────────────────────────────────────────────── */
.skip {
  position: absolute; left: -9999px; top: 0; z-index: 50;
  background: var(--blueprint); color: var(--on-accent); padding: 0.6em 1em;
}
.skip:focus { left: 0; }

/* ── header ──────────────────────────────────────────────────────────────── */
header.site {
  position: sticky; top: 0; z-index: 20;
  background: var(--header-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--rule-soft);
}
header.site .container { display: flex; align-items: center; height: var(--header-h); gap: 1.5rem; }
header.site .logo {
  font-family: var(--font-heading); color: var(--blueprint);
  text-decoration: none; font-size: 1.1rem; letter-spacing: 0.04em; white-space: nowrap;
}
header.site nav { display: flex; gap: 1.2rem; margin-left: auto; }
header.site nav a { color: var(--ink); text-decoration: none; font-size: 0.95rem; }
header.site nav a:hover { color: var(--blueprint); }

.theme-toggle {
  border: 1px solid var(--rule-soft); background: var(--bg-surface);
  width: 34px; height: 34px; line-height: 1; font-size: 1rem;
  color: var(--ink); border-radius: 2px;
}
.theme-toggle:hover { background: var(--bg-surface-hover); }

/* ── page frame: toc + reader ────────────────────────────────────────────── */
.page {
  display: grid;
  grid-template-columns: var(--toc-w) minmax(0, 1fr);
  gap: 2.5rem;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 32px;
  align-items: start;
}

.toc {
  position: sticky; top: var(--header-h);
  max-height: calc(100vh - var(--header-h));
  overflow-y: auto;
  padding: 1.5rem 0 3rem;
  border-right: 1px solid var(--rule-soft);
  padding-right: 1.2rem;
  font-size: 0.9rem;
}
.toc-title {
  font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--ink-mute); margin: 0 0 1rem;
}
.toc section { margin-bottom: 1.1rem; }
.toc h3 {
  font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-soft); font-weight: 500;
  margin: 0 0 0.35rem;
}
.toc section.on h3 { color: var(--blueprint); }
.toc ul { list-style: none; margin: 0; padding: 0; }
.toc li { margin: 0; }
.toc a {
  display: block; padding: 0.18rem 0.4rem; color: var(--ink-soft);
  text-decoration: none; border-left: 2px solid transparent; line-height: 1.35;
}
.toc a:hover { color: var(--blueprint); background: var(--bg-surface); }
.toc li.on a {
  color: var(--blueprint); font-weight: 600;
  border-left-color: var(--blueprint); background: var(--blueprint-tint);
}
.toc .n {
  font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-mute);
  display: inline-block; min-width: 1.9em;
}
.toc li.on .n { color: var(--blueprint); }

.reader { min-width: 0; padding: 2rem 0 4rem; }

/* ── lesson article ──────────────────────────────────────────────────────── */
.lesson-article { max-width: var(--read-w); margin: 0; }

.lesson-meta-tag {
  font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--ink-mute); margin: 0 0 0.6rem;
}
.lesson-motto { font-style: italic; color: var(--ink-soft); margin: 0.5em 0 1.5em; }

.lesson-meta-block {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem;
  margin: 0 0 1.5em; padding: 1em 0;
  border-top: 1px solid var(--rule-soft); border-bottom: 1px solid var(--rule-soft);
}
.lesson-meta-block dt {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--blueprint); margin-bottom: 0.2em;
}
.lesson-meta-block dd { margin: 0; font-size: 0.92rem; color: var(--ink-soft); }

.ascii-rule {
  height: 6px; margin: 2em 0;
  background: repeating-linear-gradient(90deg,
    var(--blueprint) 0 4px, transparent 4px 8px,
    var(--blueprint-tint) 8px 14px, transparent 14px 22px);
}

/* ── prose ───────────────────────────────────────────────────────────────── */
.prose { font-size: 1.03rem; }
.prose > p:first-of-type::first-letter {
  font-family: var(--font-heading); color: var(--blueprint);
  font-size: 3.6rem; float: left; line-height: 0.85;
  margin: 0.08em 0.12em 0 0;
}
.prose h2 {
  font-size: 1.45rem; margin: 2.2em 0 0.7em; padding-top: 0.6em;
  border-top: 1px solid var(--rule-soft);
}
.prose h3 { font-size: 1.12rem; margin: 1.6em 0 0.5em; }
.prose h4 { font-size: 1rem; margin: 1.4em 0 0.4em; color: var(--ink-soft); }
.prose ul, .prose ol { margin: 0 0 1.1em; padding-left: 1.4em; }
.prose li { margin: 0.3em 0; }
.prose li > ul, .prose li > ol { margin: 0.3em 0; }
.prose li.criterion {
  list-style: none; margin-left: -1.4em; padding: 0.4em 0.7em;
  background: var(--blueprint-tint); border-left: 2px solid var(--blueprint);
}
.prose blockquote {
  margin: 1.4em 0; padding: 0.2em 0 0.2em 1.1em;
  border-left: 2.5px solid var(--blueprint);
  color: var(--ink-soft); font-style: italic;
}
.prose blockquote p:last-child { margin-bottom: 0; }
.prose hr { border: 0; border-top: 1px solid var(--rule-soft); margin: 2em 0; }
.prose pre.code { position: relative; margin: 0 0 1.3em; }
.prose pre.code[data-lang]::after {
  content: attr(data-lang);
  position: absolute; top: 0; right: 0;
  font-family: var(--font-mono); font-size: 0.62rem; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-mute);
  padding: 0.25em 0.6em; background: var(--bg-surface);
}
.prose figure.diagram { margin: 1.4em 0; }
.prose figure.diagram pre { border-left-color: var(--blueprint); }
.prose figure.diagram figcaption {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--ink-mute); margin-top: 0.4em;
}
.prose a { text-decoration: underline; }

/* ── tables ──────────────────────────────────────────────────────────────── */
.table-wrap { overflow-x: auto; margin: 0 0 1.5em; }
table { width: 100%; border-collapse: collapse; font-size: 0.92rem; }
th, td {
  padding: 8px 10px; border-bottom: 1px solid var(--rule-soft);
  text-align: left; vertical-align: top;
}
th {
  font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-soft); font-weight: 500;
  white-space: nowrap;
}
/* The Key Terms table is the highest-value one on the page and its middle
   column is a sentence, not a label — nowrap would blow the layout out. */
td { white-space: normal; }
td:first-child { white-space: nowrap; }

/* ── status squares ──────────────────────────────────────────────────────── */
.status-square { display: inline-block; width: 10px; height: 10px; margin-right: 6px; vertical-align: middle; }
.status-square.complete { background: var(--complete); }
.status-square.in-progress { background: linear-gradient(to bottom right, var(--blueprint) 0 50%, transparent 50% 100%); }
.status-square.planned { border: 1px dashed var(--ink-mute); }

aside.callout {
  background: var(--blueprint-tint);
  border-left: 2.5px solid var(--blueprint);
  padding: 0.85rem 1.1rem;
  margin: 1.4rem 0;
}

/* ── buttons ─────────────────────────────────────────────────────────────── */
button { font: inherit; background: none; border: 0; cursor: pointer; color: inherit; }
button.primary { background: var(--blueprint); color: var(--on-accent); padding: 0.5em 1em; box-shadow: var(--shadow-hard); }
button.primary:active { transform: translate(2px, 2px); box-shadow: 1px 1px 0 var(--ink); }

a.button {
  display: inline-block; background: var(--blueprint); color: var(--on-accent);
  text-decoration: none; padding: 0.55em 1.1em;
  box-shadow: var(--shadow-hard); font-family: var(--font-mono);
  font-size: 0.86rem; letter-spacing: 0.02em;
}
a.button:hover { background: var(--accent-hover); }
a.button.ghost {
  background: var(--bg-surface); color: var(--ink);
  border: 1px solid var(--ink); box-shadow: var(--shadow-hard);
}
a.button.ghost:hover { background: var(--bg-surface-hover); color: var(--ink); }

/* ── hero ────────────────────────────────────────────────────────────────── */
.hero { padding: 3rem 0 1rem; max-width: var(--read-w); }
.hero h1 { font-size: clamp(2rem, 4.5vw, 3.1rem); margin-bottom: 0.4em; }
.hero .lede { font-size: 1.1rem; color: var(--ink-soft); }
.hero-actions { display: flex; gap: 0.9rem; flex-wrap: wrap; margin: 1.6em 0 2em; }

.stats {
  list-style: none; display: flex; flex-wrap: wrap; gap: 0 2.5rem;
  margin: 0 0 1rem; padding: 0;
}
.stats li { display: flex; flex-direction: column; }
.stats strong { font-family: var(--font-heading); font-size: 2rem; color: var(--blueprint); line-height: 1; }
.stats span {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-mute);
}

/* ── phase grid (home) ───────────────────────────────────────────────────── */
.phase-grid {
  display: grid; gap: 1rem;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  margin: 1.5rem 0 2rem;
}
.phase-card {
  display: block; text-decoration: none; color: var(--ink);
  background: var(--bg-surface); border: 1px solid var(--rule-soft);
  padding: 1rem 1.1rem; box-shadow: var(--shadow-hard);
  transition: transform var(--motion-feedback) var(--ease-out);
}
.phase-card:hover { transform: translate(-2px, -2px); background: var(--bg-surface-hover); }
.phase-card .pc-head { display: flex; align-items: center; justify-content: space-between; }
.phase-card .pc-num {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--blueprint);
}
.phase-card h3 { font-size: 1.15rem; margin: 0.3em 0 0.35em; color: var(--ink); }
.phase-card p { font-size: 0.9rem; color: var(--ink-soft); margin: 0 0 0.6em; }
.phase-card .pc-meta {
  font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.06em;
  color: var(--ink-mute); margin: 0;
}

/* ── catalog / glossary ──────────────────────────────────────────────────── */
.cat-phase { margin: 0 0 2.5rem; }
.cat-phase h2 { display: flex; align-items: center; font-size: 1.3rem; }
.cat-lessons { list-style: none; padding: 0; margin: 0.8rem 0; }
.cat-lessons li { padding: 0.3em 0; border-bottom: 1px solid var(--paper-rule); }
.cat-lessons a { text-decoration: none; }
.cat-lessons a:hover { text-decoration: underline; }
.cat-phase .mod { font-family: var(--font-mono); font-size: 0.78rem; color: var(--ink-soft); }

/* ── quiz ────────────────────────────────────────────────────────────────── */
.quiz {
  margin: 3rem 0 0; padding-top: 1.5rem;
  border-top: 2px solid var(--blueprint);
}
.quiz h2 { border: 0; padding-top: 0; margin-top: 0; }
.quiz-note { color: var(--ink-soft); font-size: 0.92rem; }
.quiz-list { list-style: none; padding: 0; margin: 0; counter-reset: q; }
.quiz-list > li {
  counter-increment: q; margin: 0 0 1.6rem; padding: 1rem 1.1rem;
  background: var(--bg-surface); border-left: 2.5px solid var(--blueprint);
}
.quiz-list > li::before {
  content: 'Q' counter(q);
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.14em;
  color: var(--blueprint); display: block; margin-bottom: 0.35em;
}
.quiz .q { font-weight: 600; margin-bottom: 0.6em; }
.quiz .options { margin: 0 0 0.8em; padding-left: 1.5em; }
.quiz .options li { margin: 0.25em 0; }
.quiz details { border-top: 1px solid var(--rule-soft); padding-top: 0.6em; }
.quiz summary {
  cursor: pointer; font-family: var(--font-mono); font-size: 0.72rem;
  letter-spacing: 0.1em; text-transform: uppercase; color: var(--blueprint);
}
.quiz .ans { margin: 0.7em 0 0.3em; }
.quiz .why { color: var(--ink-soft); font-size: 0.92rem; margin: 0; }

/* ── pager ───────────────────────────────────────────────────────────────── */
.pager {
  display: flex; justify-content: space-between; gap: 1rem;
  margin: 3rem 0 0; padding-top: 1.2rem; border-top: 1px solid var(--rule-soft);
}
.pager a {
  text-decoration: none; color: var(--ink); max-width: 45%;
  font-size: 0.92rem; display: flex; flex-direction: column;
}
.pager a.next { text-align: right; margin-left: auto; }
.pager a:hover { color: var(--blueprint); }
.pager a span {
  font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--ink-mute); margin-bottom: 0.2em;
}

/* ── responsive ──────────────────────────────────────────────────────────── */
@media (max-width: 1000px) {
  .page { grid-template-columns: 1fr; gap: 0; }
  .toc {
    position: static; max-height: 40vh; border-right: 0;
    border-bottom: 1px solid var(--rule-soft); padding-right: 0;
  }
  .reader { padding-top: 1rem; }
}
@media (max-width: 640px) {
  html { font-size: 16px; }
  .container, .page { padding: 0 18px; }
  .lesson-meta-block { grid-template-columns: 1fr; gap: 0.6rem; }
  header.site nav { gap: 0.8rem; font-size: 0.85rem; }
  header.site .logo { font-size: 0.95rem; }
  .pager a { max-width: 100%; }
}

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