/* Shared course stylesheet — Tufte-inspired, print-friendly */
:root {
  --ink: #1a1a1a;
  --muted: #5c5c5c;
  --paper: #f7f4ef;
  --rule: #d4cfc4;
  --accent: #0b4f6c;
  --ok: #1b6b3a;
  --bad: #8b1e1e;
  --code-bg: #efeae2;
  --max: 42rem;
  --side: 14rem;
  font-family: "Source Serif 4", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
}

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

html {
  font-size: 18px;
  line-height: 1.55;
  color: var(--ink);
  background: var(--paper);
}

body {
  margin: 0;
  padding: 2.5rem 1.25rem 4rem;
}

.wrap {
  max-width: calc(var(--max) + var(--side) + 2rem);
  margin: 0 auto;
}

header.site {
  margin-bottom: 2.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--rule);
}

header.site .eyebrow {
  font-family: "IBM Plex Sans", "Source Sans 3", system-ui, sans-serif;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 0.35rem;
}

header.site h1 {
  font-size: 1.85rem;
  font-weight: 600;
  line-height: 1.25;
  margin: 0 0 0.5rem;
  letter-spacing: -0.02em;
}

header.site .lede {
  margin: 0;
  color: var(--muted);
  max-width: var(--max);
}

main {
  display: grid;
  grid-template-columns: minmax(0, var(--max)) minmax(0, var(--side));
  gap: 2rem 2.5rem;
  align-items: start;
}

article {
  max-width: var(--max);
}

aside.margin {
  font-family: "IBM Plex Sans", "Source Sans 3", system-ui, sans-serif;
  font-size: 0.8rem;
  line-height: 1.45;
  color: var(--muted);
  position: sticky;
  top: 1.5rem;
}

aside.margin h2 {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink);
  margin: 0 0 0.5rem;
}

aside.margin ul {
  margin: 0;
  padding-left: 1.1rem;
}

aside.margin a {
  color: var(--accent);
}

aside.margin .nav-block {
  margin-bottom: 1.25rem;
}

aside.margin .nav-block:last-child {
  margin-bottom: 0;
}

aside.margin li.current > span {
  color: var(--ink);
  font-weight: 600;
}

h2 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 2rem 0 0.75rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
}

p,
ul,
ol {
  margin: 0 0 1rem;
}

ul,
ol {
  padding-left: 1.25rem;
}

a {
  color: var(--accent);
}

code,
pre {
  font-family: "IBM Plex Mono", "Source Code Pro", ui-monospace, monospace;
  font-size: 0.86em;
}

code {
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}

pre {
  background: var(--code-bg);
  padding: 0.9rem 1rem;
  overflow-x: auto;
  border-radius: 4px;
  margin: 0 0 1.25rem;
  line-height: 1.4;
}

pre code {
  background: none;
  padding: 0;
}

.diagram {
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.78rem;
  line-height: 1.35;
  background: var(--code-bg);
  padding: 1rem;
  margin: 0 0 1.25rem;
  overflow-x: auto;
  white-space: pre;
  border-left: 3px solid var(--accent);
}

.callout {
  border-left: 3px solid var(--accent);
  padding: 0.15rem 0 0.15rem 1rem;
  margin: 1.25rem 0;
  color: var(--muted);
}

.callout strong {
  color: var(--ink);
}

.quiz {
  margin: 1.5rem 0 2rem;
  padding: 1.25rem;
  border: 1px solid var(--rule);
  background: #fffefb;
}

.quiz h3 {
  margin-top: 0;
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 0.95rem;
}

.quiz .q {
  margin-bottom: 1.25rem;
}

.quiz .q:last-child {
  margin-bottom: 0;
}

.quiz .prompt {
  margin: 0 0 0.6rem;
  font-weight: 500;
}

.quiz .choices {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.quiz button.choice {
  font: inherit;
  text-align: left;
  padding: 0.55rem 0.75rem;
  border: 1px solid var(--rule);
  background: #fff;
  cursor: pointer;
  border-radius: 3px;
  color: var(--ink);
}

.quiz button.choice:hover:not(:disabled) {
  border-color: var(--accent);
}

.quiz button.choice:disabled {
  cursor: default;
}

.quiz button.choice.correct {
  border-color: var(--ok);
  background: #e8f5ec;
}

.quiz button.choice.wrong {
  border-color: var(--bad);
  background: #f8eaea;
}

.quiz .feedback {
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 0.85rem;
  margin: 0.5rem 0 0;
  min-height: 1.2em;
}

.quiz .feedback.ok {
  color: var(--ok);
}

.quiz .feedback.bad {
  color: var(--bad);
}

footer.lesson {
  max-width: var(--max);
  margin-top: 3rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--rule);
  font-size: 0.95rem;
  color: var(--muted);
}

footer.lesson a {
  color: var(--accent);
}

/* Glossary: tool groups + definition layout */
.glossary-index {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.65rem;
  margin: 0 0 2rem;
  padding: 0 0 1.25rem;
  border-bottom: 1px solid var(--rule);
  font-family: "IBM Plex Sans", "Source Sans 3", system-ui, sans-serif;
  font-size: 0.85rem;
}

.glossary-index a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
  padding-bottom: 0.05rem;
}

.glossary-index a:hover {
  border-bottom-color: var(--accent);
}

.glossary-tool {
  margin: 0 0 2.75rem;
  padding: 0 0 0 1rem;
  border-left: 3px solid var(--rule);
}

.glossary-tool:last-child {
  margin-bottom: 0;
}

.glossary-tool-head {
  margin: 0 0 1.25rem;
}

.glossary-tool-label {
  font-family: "IBM Plex Sans", "Source Sans 3", system-ui, sans-serif;
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 0.35rem;
}

.glossary-tool-head h2 {
  margin: 0 0 0.5rem;
  font-size: 1.35rem;
}

.glossary-tool-head p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.glossary-defs {
  margin: 0;
}

.glossary-entry {
  display: grid;
  grid-template-columns: minmax(7rem, 11rem) minmax(0, 1fr);
  gap: 0.5rem 1.25rem;
  padding: 0.85rem 0;
  border-top: 1px solid var(--rule);
  align-items: baseline;
}

.glossary-entry:last-child {
  border-bottom: 1px solid var(--rule);
}

.glossary-entry dt {
  font-family: "IBM Plex Sans", "Source Sans 3", system-ui, sans-serif;
  font-weight: 600;
  font-size: 0.92rem;
  margin: 0;
  scroll-margin-top: 1.5rem;
}

.glossary-entry dt code {
  font-size: 0.9em;
}

.glossary-entry dd {
  margin: 0;
  color: var(--ink);
  font-size: 0.95rem;
}

.glossary-entry:target,
.glossary-entry:has(> dt:target) {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  margin: 0 -0.5rem;
  padding-left: 0.5rem;
  padding-right: 0.5rem;
  border-radius: 3px;
}

.glossary-entry dt:target {
  color: var(--accent);
}

@media (max-width: 640px) {
  .glossary-tool {
    padding-left: 0.75rem;
  }

  .glossary-entry {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }
}

@media print {
  .glossary-index {
    border-bottom-color: #999;
  }

  .glossary-tool {
    border-left-color: #999;
    break-inside: avoid;
  }
}

@media (max-width: 900px) {
  main {
    grid-template-columns: 1fr;
  }

  aside.margin {
    position: static;
    order: -1;
    padding: 0.75rem 0 0;
    border-top: 1px solid var(--rule);
  }
}

@media print {
  html {
    background: #fff;
    font-size: 11pt;
  }

  body {
    padding: 0;
  }

  aside.margin {
    position: static;
  }

  .quiz button.choice {
    border: 1px solid #999;
  }
}