/*
 * Game Servers at Scale — shared typography and reusable widget styling.
 * Linked by every lesson and reference page in this course via frontmatter `styles`.
 * The Astro app supplies the page shell and layout primitives (see ../../lesson-pages);
 * this file owns the reading experience and the course's own components.
 *
 * Forked from ../../trig/assets/course.css. The prose system, .note, .recall, .figure and
 * .quiz rules are deliberately identical — a fix to any of them belongs in both courses.
 * Course-specific additions: .arith (worked arithmetic) and .bandwidth-lab.
 */

:root {
  --learning-accent: #2f6b3f;

  --gs-measure: 35rem;
  --gs-serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --gs-sans: system-ui, -apple-system, "Segoe UI", sans-serif;
  --gs-mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  --gs-good: #2f6b3f;
  --gs-bad: #a11c2b;
  --gs-neutral: #6b6257;
}

body {
  font-family: var(--gs-serif);
  font-size: clamp(1.02rem, 0.98rem + 0.25vw, 1.18rem);
  line-height: 1.62;
  text-rendering: optimizeLegibility;
}

/* Tufte-ish column: prose sits in a narrow measure, figures and widgets run wide. */
.lesson-content > p,
.lesson-content > ul,
.lesson-content > ol,
.lesson-content > dl,
.lesson-content > h2,
.lesson-content > h3,
.lesson-content > h4,
.lesson-content > blockquote,
.lesson-content > table,
.lesson-content > .measured {
  max-width: var(--gs-measure);
}

.lesson-header .eyebrow {
  margin: 0 0 .5rem;
  color: var(--learning-muted);
  font-family: var(--gs-sans);
  font-size: .72rem;
  font-weight: 650;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.lesson-header h1 {
  max-width: 24ch;
  margin: 0;
  font-size: clamp(2rem, 1.5rem + 2.2vw, 3rem);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -.015em;
}

.lesson-header .lede {
  max-width: var(--gs-measure);
  margin: .75rem 0 0;
  color: var(--learning-muted);
  font-size: 1.15rem;
  font-style: italic;
}

.lesson-content h2 {
  margin: 3rem 0 .75rem;
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -.01em;
}

.lesson-content h3 {
  margin: 2rem 0 .5rem;
  font-size: 1.18rem;
  font-weight: 650;
}

.lesson-content a {
  color: inherit;
  text-decoration-color: color-mix(in srgb, var(--learning-accent) 55%, transparent);
  text-decoration-thickness: 1px;
  text-underline-offset: .16em;
}

.lesson-content a:hover,
.lesson-content a:focus-visible { text-decoration-color: var(--learning-accent); }

code, kbd, samp { font-family: var(--gs-mono); font-size: .88em; }

:not(pre) > code {
  padding: .1em .32em;
  border-radius: .25em;
  background: color-mix(in srgb, currentColor 7%, transparent);
}

pre {
  max-width: 48rem;
  padding: 1rem 1.15rem;
  border: 1px solid var(--learning-rule);
  border-left: 3px solid color-mix(in srgb, var(--learning-accent) 60%, transparent);
  border-radius: .4rem;
  background: color-mix(in srgb, var(--learning-ink) 4%, transparent);
  font-size: .82rem;
  line-height: 1.55;
}

blockquote {
  margin-inline: 0;
  padding-left: 1.1rem;
  border-left: 2px solid var(--learning-rule);
  color: var(--learning-muted);
  font-style: italic;
}

/* --- Components ---------------------------------------------------------- */

/* Aside: a margin note that stays inline on narrow screens. */
.note {
  max-width: var(--gs-measure);
  margin: 1.5rem 0;
  padding: .85rem 1.1rem;
  border-left: 3px solid color-mix(in srgb, var(--learning-accent) 45%, transparent);
  background: color-mix(in srgb, var(--learning-accent) 5%, transparent);
  font-size: .94rem;
}

.note > :first-child { margin-top: 0; }
.note > :last-child { margin-bottom: 0; }

.note--trap {
  border-left-color: color-mix(in srgb, var(--gs-bad) 55%, transparent);
  background: color-mix(in srgb, var(--gs-bad) 5%, transparent);
}

.note--source,
.note--ask {
  border-left-color: color-mix(in srgb, var(--gs-neutral) 55%, transparent);
  background: color-mix(in srgb, var(--gs-neutral) 6%, transparent);
}

.note__label {
  display: block;
  margin-bottom: .3rem;
  font-family: var(--gs-sans);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
}

/* Worked arithmetic: the course's central habit is multiplying the numbers out loud. */
.arith {
  max-width: 42rem;
  margin: 1.75rem 0;
  padding: 1rem 1.2rem;
  border: 1px solid var(--learning-rule);
  border-radius: .5rem;
  background: color-mix(in srgb, var(--learning-ink) 3%, transparent);
  font-family: var(--gs-mono);
  font-size: .86rem;
  line-height: 1.7;
}

.arith__label {
  display: block;
  margin-bottom: .5rem;
  font-family: var(--gs-sans);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--learning-muted);
}

.arith__row { display: block; }
.arith__row + .arith__row { margin-top: .15rem; }
.arith__result { font-weight: 700; }
.arith__result.is-bad { color: var(--gs-bad); }
.arith__result.is-good { color: var(--gs-good); }

.arith__rule {
  display: block;
  margin: .5rem 0;
  border-top: 1px solid var(--learning-rule);
}

/* Figure: full-width block for widgets and diagrams. */
.figure { margin: 2.25rem 0; }

.figure > figcaption {
  max-width: var(--gs-measure);
  margin-top: .7rem;
  color: var(--learning-muted);
  font-size: .88rem;
  line-height: 1.5;
}

/* Recall card: native <details>, no JavaScript needed. */
.recall {
  max-width: var(--gs-measure);
  margin: 1.25rem 0;
  padding: .3rem .95rem;
  border: 1px solid var(--learning-rule);
  border-radius: .5rem;
  background: color-mix(in srgb, var(--learning-ink) 2.5%, transparent);
}

.recall > summary {
  padding: .55rem 0;
  font-family: var(--gs-sans);
  font-size: .9rem;
  font-weight: 600;
  cursor: pointer;
}

.recall > summary:focus-visible { outline: 2px solid var(--learning-accent); outline-offset: 3px; }
.recall[open] > summary { margin-bottom: .2rem; border-bottom: 1px solid var(--learning-rule); }
.recall > :last-child { margin-bottom: .8rem; }

/* Bandwidth lab — see bandwidth-lab.js */
.bandwidth-lab {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: minmax(0, 1fr);
  align-items: start;
  padding: 1.25rem;
  border: 1px solid var(--learning-rule);
  border-radius: .6rem;
  background: color-mix(in srgb, var(--learning-ink) 2.5%, transparent);
  font-family: var(--gs-sans);
}

@media (min-width: 48rem) {
  .bandwidth-lab { grid-template-columns: minmax(0, 17rem) minmax(0, 1fr); }
}

.bandwidth-lab__controls { display: grid; gap: 1rem; }

.bandwidth-lab__field { display: block; }

.bandwidth-lab__label {
  display: flex;
  justify-content: space-between;
  gap: .5rem;
  margin-bottom: .3rem;
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--learning-muted);
}

.bandwidth-lab__value {
  font-family: var(--gs-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
  text-transform: none;
  color: var(--learning-ink);
}

.bandwidth-lab__field input[type="range"] { width: 100%; accent-color: var(--learning-accent); }
.bandwidth-lab__field input[type="range"]:focus-visible { outline: 2px solid var(--learning-accent); outline-offset: 3px; }

.bandwidth-lab__bars { display: grid; gap: 1.1rem; }

.bandwidth-lab__bar { display: block; }

.bandwidth-lab__barhead {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: .3rem;
}

.bandwidth-lab__name { font-size: .9rem; font-weight: 650; }

.bandwidth-lab__rate {
  font-family: var(--gs-mono);
  font-size: .95rem;
  font-variant-numeric: tabular-nums;
  font-weight: 700;
}

.bandwidth-lab__track {
  position: relative;
  height: .85rem;
  border-radius: .45rem;
  background: color-mix(in srgb, var(--learning-ink) 8%, transparent);
  overflow: hidden;
}

.bandwidth-lab__fill {
  height: 100%;
  border-radius: .45rem;
  transition: width .12s linear;
}

.bandwidth-lab__bar[data-tone="bad"] .bandwidth-lab__fill { background: var(--gs-bad); }
.bandwidth-lab__bar[data-tone="bad"] .bandwidth-lab__rate { color: var(--gs-bad); }
.bandwidth-lab__bar[data-tone="good"] .bandwidth-lab__fill { background: var(--gs-good); }
.bandwidth-lab__bar[data-tone="good"] .bandwidth-lab__rate { color: var(--gs-good); }

.bandwidth-lab__note {
  margin: .25rem 0 0;
  color: var(--learning-muted);
  font-size: .8rem;
  line-height: 1.45;
}

.bandwidth-lab__scale {
  margin: .1rem 0 0;
  color: var(--learning-muted);
  font-size: .78rem;
}

.bandwidth-lab__status {
  margin: .6rem 0 0;
  min-height: 2.4em;
  font-size: .86rem;
  line-height: 1.5;
}

/* Quiz widget — see quiz.js. Works without JavaScript; JS adds instant feedback. */
.quiz {
  max-width: 42rem;
  margin: 2rem 0;
  padding: 1.25rem 1.4rem;
  border: 1px solid var(--learning-rule);
  border-radius: .6rem;
  background: color-mix(in srgb, var(--learning-ink) 2.5%, transparent);
  font-family: var(--gs-sans);
}

.quiz > h2, .quiz > h3 { margin-top: 0; }

.quiz__q { margin: 0 0 1.5rem; padding: 0; border: 0; }
.quiz__q:last-of-type { margin-bottom: .5rem; }

.quiz__q > legend {
  padding: 0;
  margin-bottom: .6rem;
  font-family: var(--gs-serif);
  font-size: 1.02rem;
  font-weight: 600;
}

.quiz__option {
  display: flex;
  gap: .6rem;
  align-items: baseline;
  padding: .45rem .6rem;
  border: 1px solid transparent;
  border-radius: .35rem;
  font-size: .95rem;
  cursor: pointer;
}

.quiz__option:hover { background: color-mix(in srgb, currentColor 6%, transparent); }
.quiz__option input { accent-color: var(--learning-accent); }
.quiz__option:focus-within { outline: 2px solid var(--learning-accent); outline-offset: 1px; }

.quiz__option[data-state="right"] {
  border-color: color-mix(in srgb, var(--gs-good) 45%, transparent);
  background: color-mix(in srgb, var(--gs-good) 10%, transparent);
}

.quiz__option[data-state="wrong"] {
  border-color: color-mix(in srgb, var(--gs-bad) 45%, transparent);
  background: color-mix(in srgb, var(--gs-bad) 8%, transparent);
}

.quiz__mark { margin-left: auto; font-weight: 700; }
.quiz__option[data-state="right"] .quiz__mark { color: var(--gs-good); }
.quiz__option[data-state="wrong"] .quiz__mark { color: var(--gs-bad); }

.quiz__explain {
  margin: .6rem 0 0;
  padding-left: .6rem;
  border-left: 2px solid var(--learning-rule);
  color: var(--learning-muted);
  font-size: .9rem;
  line-height: 1.5;
}

.quiz__score { margin: 0; font-size: .9rem; font-weight: 600; min-height: 1.2em; }

.quiz__reset {
  margin-top: .8rem;
  padding: .35rem .7rem;
  border: 1px solid var(--learning-rule);
  border-radius: .3rem;
  background: transparent;
  color: inherit;
  font: inherit;
  font-size: .84rem;
  cursor: pointer;
}

.quiz__reset:hover { background: color-mix(in srgb, var(--learning-accent) 12%, transparent); }
.quiz__reset:focus-visible { outline: 2px solid var(--learning-accent); outline-offset: 2px; }

/* Reference tables */
.lesson-content table { border-collapse: collapse; font-size: .92rem; }
.lesson-content th, .lesson-content td { padding: .4rem .8rem .4rem 0; text-align: left; }
.lesson-content thead th { border-bottom: 1px solid var(--learning-ink); font-family: var(--gs-sans); font-size: .78rem; letter-spacing: .05em; text-transform: uppercase; }
.lesson-content tbody tr + tr td { border-top: 1px solid var(--learning-rule); }

/* Print: reference pages should survive a trip to paper. */
@media print {
  :root { --gs-measure: none; }
  body { background: #fff; font-size: 10.5pt; }
  .learning-home, .course-navigator, .learning-footer, .lesson-podcast,
  .bandwidth-lab__controls, .bandwidth-lab__status { display: none !important; }
  .lesson-content { width: auto; }
  .recall[open], .recall { break-inside: avoid; }
  .quiz, .note, .figure, .arith { break-inside: avoid; }
  .recall > summary { list-style: none; }
  .lesson-content a { text-decoration: none; }
  .lesson-content a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 8pt; word-break: break-all; }
}