/* eli5 — the shared design for every explainer in this archive.
 *
 * Each page used to bring its own palette, its own three fonts and its own
 * names for the same six things (step / beat / scene / page for one numbered
 * section). The drawings are what differ between explainers; the furniture
 * around them never did. So the furniture lives here, once.
 *
 * A page may still carry a <style> block, but only to animate or position its
 * own illustrations. Everything below — colour, type, spacing, the shape of a
 * step — is settled here and must not be redefined per page.
 *
 * Illustrations should paint with the tokens rather than with literal colours.
 * An <svg> drawn in var(--e-ink) and var(--e-accent) follows the reader into
 * dark mode for free; one drawn in #14302C does not.
 */

:root {
  color-scheme: light dark;

  --e-ground: #e6ece8;
  --e-surface: #f5f8f5;
  --e-sunk: #dce5e0;
  --e-ink: #14302c;
  --e-ink-soft: #4e6b66;
  --e-line: #c6d3cd;

  /* the three voices a picture story needs: neutral, wrong, fixed */
  --e-accent: #2c6a5f;
  --e-warn: #a03d28;
  --e-mark: #a9781f;

  --e-shadow: 0 1px 0 rgb(20 48 44 / 6%), 0 8px 24px -14px rgb(20 48 44 / 35%);

  --e-display: "Zen Maru Gothic", "Hiragino Maru Gothic ProN", "Yu Gothic", sans-serif;
  --e-body: "Zen Kaku Gothic New", "Hiragino Sans", "Yu Gothic", system-ui, sans-serif;
  --e-mono: "DM Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  /* one spacing step, so every gap on the page is a multiple of the same thing */
  --e-step: clamp(1rem, 0.6rem + 1.4vw, 1.5rem);
  --e-maxw: 1120px;
  --e-radius: 18px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --e-ground: #0e1e1c;
    --e-surface: #152b28;
    --e-sunk: #0a1716;
    --e-ink: #e4ede9;
    --e-ink-soft: #93aaa5;
    --e-line: #244440;

    --e-accent: #4f9d8d;
    --e-warn: #de7259;
    --e-mark: #d9a94e;

    --e-shadow: 0 1px 0 rgb(0 0 0 / 30%), 0 10px 28px -16px rgb(0 0 0 / 80%);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--e-ground);
  color: var(--e-ink);
  font-family: var(--e-body);
  font-size: clamp(1rem, 0.94rem + 0.28vw, 1.125rem);
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
}

/* the link back to the index, injected into every page */
.eli5-up {
  display: inline-block;
  margin: 1.25rem 0 0 1.25rem;
  font-family: var(--e-mono);
  font-size: 0.8125rem;
  line-height: 1;
  color: var(--e-ink-soft);
  text-decoration: none;
}

.eli5-up:hover,
.eli5-up:focus-visible {
  color: var(--e-ink);
  text-decoration: underline;
}

.e-page {
  max-width: var(--e-maxw);
  margin: 0 auto;
  padding: 0 var(--e-step);
}

/* ---------- opening ---------- */

.e-head {
  display: grid;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
  padding: clamp(2rem, 6vw, 4.5rem) 0 clamp(2rem, 5vw, 3.5rem);
}

/* the art sits beside the title only when there is room for both to breathe */
@media (min-width: 820px) {
  .e-head:has(.e-head-art) {
    grid-template-columns: 1.15fr 0.85fr;
  }
}

.e-eyebrow {
  margin: 0 0 0.9rem;
  font-family: var(--e-mono);
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--e-mark);
}

.e-head h1 {
  margin: 0 0 1rem;
  font-family: var(--e-display);
  font-weight: 700;
  font-size: clamp(2.1rem, 1.3rem + 4vw, 4rem);
  line-height: 1.18;
  text-wrap: balance;
}

.e-lede {
  margin: 0;
  max-width: 34em;
  font-size: clamp(1.05rem, 0.98rem + 0.4vw, 1.3rem);
  color: var(--e-ink-soft);
}

.e-head-art {
  display: grid;
  place-items: center;
}

.e-head-art svg {
  width: 100%;
  max-width: 380px;
  height: auto;
}

/* ---------- the numbered steps ---------- */

.e-steps {
  display: flex;
  flex-direction: column;
  gap: clamp(1rem, 2.5vw, 1.75rem);
  padding-bottom: clamp(2rem, 5vw, 4rem);
}

.e-step {
  padding: clamp(1.25rem, 3vw, 2.25rem);
  background: var(--e-surface);
  border: 1px solid var(--e-line);
  border-radius: var(--e-radius);
  box-shadow: var(--e-shadow);
  display: grid;
  gap: clamp(1rem, 2.5vw, 2rem);
}

/* a step that shows the fault, and one that shows the repair */
.e-step--bad {
  border-color: color-mix(in srgb, var(--e-warn) 45%, var(--e-line));
}

.e-step--good {
  border-color: color-mix(in srgb, var(--e-accent) 45%, var(--e-line));
}

.e-step-head {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.e-num {
  font-family: var(--e-mono);
  font-size: 0.85rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.1em;
  color: var(--e-ink-soft);
}

.e-step h2 {
  margin: 0;
  font-family: var(--e-display);
  font-weight: 700;
  font-size: clamp(1.25rem, 1.1rem + 0.7vw, 1.6rem);
  line-height: 1.4;
}

.e-step p {
  margin: 0 0 0.9em;
}

.e-step p:last-child {
  margin-bottom: 0;
}

.e-chip {
  padding: 0.2rem 0.7rem 0.28rem;
  border: 1.5px solid currentcolor;
  border-radius: 999px;
  font-family: var(--e-display);
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--e-ink-soft);
}

.e-chip--problem {
  color: var(--e-warn);
}

.e-chip--fix {
  color: var(--e-accent);
}

/* prose on one side, the drawing on the other */
.e-two {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2.5rem);
  align-items: center;
}

@media (min-width: 760px) {
  .e-two {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  }
}

/* ---------- illustrations ---------- */

/* stretch, not centre: a bar chart or a table placed here needs the full width,
   and only the drawing itself wants to be centred */
.e-fig {
  margin: 0;
  display: grid;
  gap: 0.75rem;
}

.e-fig svg {
  width: 100%;
  height: auto;
  max-width: 520px;
  margin-inline: auto;
  overflow: visible;
}

/* a ground for drawings whose strokes would otherwise float on the card */
.e-fig--panel {
  padding: clamp(0.75rem, 2vw, 1.25rem);
  background: var(--e-sunk);
  border-radius: 12px;
  overflow-x: auto;
  justify-items: stretch;
}

.e-fig--panel svg {
  max-width: none;
  min-width: 320px;
}

.e-fig figcaption {
  font-family: var(--e-mono);
  font-size: 0.78rem;
  line-height: 1.6;
  text-align: center;
  color: var(--e-ink-soft);
  text-wrap: balance;
}

/* an aside the eye should stop on, without becoming a card of its own */
.e-note {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding-left: 1.2rem;
  border-left: 3px solid var(--e-accent);
}

/* a handful of labelled facts, side by side */
.e-tally {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--e-line);
  border: 1px solid var(--e-line);
  border-radius: 8px;
  overflow: hidden;
}

.e-tally > div {
  padding: 0.9rem 1rem;
  background: var(--e-surface);
}

.e-tally dt {
  font-family: var(--e-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--e-ink-soft);
}

.e-tally dd {
  margin: 0.35rem 0 0;
  font-family: var(--e-display);
  font-weight: 700;
  font-size: 1.05rem;
}

.e-tally dd small {
  display: block;
  font-family: var(--e-body);
  font-weight: 400;
  font-size: 0.8rem;
  color: var(--e-ink-soft);
}

/* ---------- metaphor to reality ---------- */

.e-map {
  overflow-x: auto;
  border: 1px solid var(--e-line);
  border-radius: var(--e-radius);
  background: var(--e-sunk);
}

.e-map table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.e-map th,
.e-map td {
  padding: 0.6rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--e-line);
}

.e-map tr:last-child th,
.e-map tr:last-child td {
  border-bottom: 0;
}

.e-map th {
  font-family: var(--e-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--e-ink-soft);
  font-weight: 400;
}

/* the right-hand column is the un-metaphored truth */
.e-map td:last-child {
  font-family: var(--e-mono);
  font-size: 0.85rem;
  color: var(--e-accent);
}

/* ---------- measured numbers ---------- */

.e-bars {
  display: grid;
  gap: 0.6rem;
}

.e-bar {
  display: grid;
  grid-template-columns: minmax(6rem, auto) 1fr minmax(3.5rem, auto);
  gap: 0.75rem;
  align-items: center;
  font-size: 0.9rem;
}

/* these are spans in the markup, so they need to be told they are boxes --
   an inline element ignores width, which silently makes every bar look full */
.e-bar-track {
  display: block;
  height: 0.6rem;
  border-radius: 999px;
  background: var(--e-sunk);
  border: 1px solid var(--e-line);
  overflow: hidden;
}

/* width comes from a style attribute: the value is data, not design */
.e-bar-fill {
  display: block;
  height: 100%;
  background: var(--e-accent);
}

.e-bar--slow .e-bar-fill {
  background: var(--e-warn);
}

.e-bar-num {
  font-family: var(--e-mono);
  font-variant-numeric: tabular-nums;
  text-align: right;
  color: var(--e-ink-soft);
}

/* ---------- closing ---------- */

.e-close {
  margin: clamp(1rem, 2.5vw, 1.75rem) 0 0;
  padding: clamp(1.5rem, 3.5vw, 2.5rem);
  border: 1px solid var(--e-line);
  border-left: 4px solid var(--e-mark);
  border-radius: var(--e-radius);
  background: var(--e-surface);
}

.e-close h2 {
  margin: 0 0 0.6rem;
  font-family: var(--e-display);
  font-size: clamp(1.15rem, 1.05rem + 0.5vw, 1.4rem);
}

.e-close p:last-child {
  margin-bottom: 0;
}

.e-foot {
  padding: clamp(2rem, 5vw, 3.5rem) 0;
  font-family: var(--e-mono);
  font-size: 0.78rem;
  color: var(--e-ink-soft);
}

/* ---------- inline ---------- */

.e-step strong,
.e-close strong {
  color: var(--e-ink);
  font-weight: 700;
  background: linear-gradient(transparent 62%, color-mix(in srgb, var(--e-mark) 30%, transparent) 0);
}

/* the two verdicts a picture story keeps making, and the voice of a caption */
.e-bad {
  color: var(--e-warn);
  font-weight: 700;
}

.e-good {
  color: var(--e-accent);
  font-weight: 700;
}

.e-say {
  font-family: var(--e-mono);
  font-size: 0.85em;
  color: var(--e-mark);
}

.e-step code,
.e-close code {
  padding: 0.1em 0.4em;
  border-radius: 5px;
  background: var(--e-sunk);
  font-family: var(--e-mono);
  font-size: 0.88em;
}

/* every page enters the same way, so the archive feels like one publication */
@media (prefers-reduced-motion: no-preference) {
  .e-head,
  .e-step {
    animation: e-rise 0.5s ease-out both;
  }

  .e-step:nth-of-type(2) {
    animation-delay: 0.04s;
  }

  .e-step:nth-of-type(n + 3) {
    animation-delay: 0.08s;
  }

  @keyframes e-rise {
    from {
      opacity: 0;
      transform: translateY(10px);
    }
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

a:focus-visible,
[tabindex]:focus-visible {
  outline: 2.5px solid var(--e-mark);
  outline-offset: 3px;
  border-radius: 4px;
}