:root {
  --paper: #f8f5ee;
  --paper-deep: #eee8dc;
  --ink: #20252b;
  --muted: #5e666d;
  --rule: #c9c1b4;
  --accent: #8d3f2f;
  --accent-dark: #642b22;
  --highlight: #e6d7ad;
  --sans: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --serif: Georgia, "Times New Roman", serif;
  --measure: 72rem;
  --reading-size: 1.08rem;
  --diagram-text-size: 1rem;
  --leading: 1.75;
}

[data-font-size="xs"] { --reading-size: .94rem; --diagram-text-size: .88rem; }
[data-font-size="s"] { --reading-size: 1rem; --diagram-text-size: .94rem; }
[data-font-size="m"] { --reading-size: 1.08rem; --diagram-text-size: 1rem; }
[data-font-size="l"] { --reading-size: 1.18rem; --diagram-text-size: 1.08rem; }
[data-font-size="xl"] { --reading-size: 1.3rem; --diagram-text-size: 1.16rem; }

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-size: var(--reading-size);
  line-height: var(--leading);
  overflow-x: hidden;
}

a { color: var(--accent-dark); }
a:hover { color: var(--accent); }
a:focus-visible, button:focus-visible, select:focus-visible, textarea:focus-visible, [data-study-id]:focus-visible, .concept-figure__graphic:focus-visible { outline: 3px solid #2b6f8a; outline-offset: 3px; }

.skip-link {
  position: fixed;
  z-index: 50;
  top: .6rem;
  left: .6rem;
  padding: .6rem .8rem;
  border: 2px solid var(--ink);
  background: #fffdf8;
  color: var(--ink);
  font: 700 .9rem/1.2 var(--sans);
  transform: translateY(calc(-100% - 1rem));
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--paper-deep);
}
.site-header__inner, .page-shell {
  width: min(100% - 2rem, var(--measure));
  margin-inline: auto;
}
.site-header__inner {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
}
.wordmark { font: 700 1rem/1.2 var(--sans); letter-spacing: .08em; text-transform: uppercase; }
.course-label { color: var(--muted); font: .82rem/1.2 var(--sans); }

.page-shell {
  display: grid;
  grid-template-columns: minmax(11rem, 16rem) minmax(0, 1fr);
  gap: clamp(2rem, 6vw, 5rem);
  padding: 3rem 0 5rem;
}
.local-nav {
  align-self: start;
  position: sticky;
  top: 1.25rem;
  font: .84rem/1.45 var(--sans);
}
.local-nav__title { margin: 0 0 .65rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; }
.local-nav-toggle {
  display: none;
  margin: 0 0 .65rem;
  padding: .45rem .7rem;
  border: 1px solid var(--rule);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font: 700 .8rem/1.2 var(--sans);
}
.local-nav ol { margin: 0; padding-left: 1.2rem; }
.local-nav li { margin: .45rem 0; }
.font-tools { margin-top: 2rem; padding-top: 1rem; border-top: 1px solid var(--rule); }
.font-tools__label { display: block; margin-bottom: .5rem; font-weight: 700; }
.font-tools__buttons { display: flex; flex-wrap: wrap; gap: .3rem; }
.font-button {
  min-width: 2.3rem;
  padding: .3rem .45rem;
  border: 1px solid var(--rule);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font: 700 .78rem var(--sans);
}
.font-button[aria-pressed="true"] { background: var(--ink); color: var(--paper); border-color: var(--ink); }

main { min-width: 0; overflow-x: hidden; }
.kicker { margin: 0 0 .75rem; color: var(--accent); font: 700 .78rem/1.2 var(--sans); letter-spacing: .12em; text-transform: uppercase; }
h1, h2, h3 { color: var(--ink); font-family: var(--sans); line-height: 1.16; }
h1 { max-width: 15ch; margin: 0 0 1rem; font-size: clamp(2.5rem, 6vw, 5.2rem); letter-spacing: -.045em; }
h2 { margin-top: 3rem; font-size: clamp(1.45rem, 3vw, 2.2rem); }
h3 { margin-top: 2rem; font-size: 1.1rem; }
.dek { max-width: 44rem; margin: 0 0 2rem; color: var(--muted); font-size: 1.25em; }
.meta-line { display: flex; flex-wrap: wrap; gap: .5rem 1rem; color: var(--muted); font: .78rem var(--sans); }
.rule { border: 0; border-top: 1px solid var(--rule); margin: 2.5rem 0; }
.lead-note { padding: 1rem 1.25rem; border-left: .35rem solid var(--accent); background: #f0e8da; }
.section-intro { color: var(--muted); }
.reading-body p { max-width: 48rem; }
.reading-body { column-count: 1; max-width: 58rem; }
.reading-body h2, .reading-body h3, .reading-body table, .reading-body ul, .reading-body ol { break-inside: avoid; }
.reading-body h2 { break-before: auto; }
.placeholder { color: var(--muted); font-style: italic; }
.learning-map { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin: 1.5rem 0; }
.learning-map__item { padding: 1rem; border-top: 3px solid var(--accent); background: #f0e8da; }
.learning-map__item strong { display: block; margin-bottom: .35rem; font-family: var(--sans); }

.study-tools {
  margin: 2rem 0 2.5rem;
  padding: 1.25rem;
  border: 1px solid var(--rule);
  border-top: .35rem solid var(--accent);
  background: #fffdf8;
}
.study-tools h2 { margin: 0 0 .5rem; font-size: 1.35rem; }
.study-tools__intro { margin: 0 0 1rem; color: var(--muted); font: .92rem/1.55 var(--sans); }
.study-tools__row { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }
.study-tools__row + .study-tools__row { margin-top: .75rem; }
.study-tool-button {
  padding: .55rem .75rem;
  border: 1px solid var(--ink);
  background: var(--paper-deep);
  color: var(--ink);
  cursor: pointer;
  font: 700 .82rem/1.2 var(--sans);
}
.study-tool-button:hover { background: var(--highlight); }
.study-tool-button[data-study-action="save"] { background: var(--ink); color: var(--paper); }
.study-tool-button[data-study-action="clear-record"] { border-color: var(--accent); color: var(--accent-dark); }
.study-tools__status { min-height: 1.5em; margin: .8rem 0 0; color: var(--muted); font: .86rem/1.45 var(--sans); }
.study-tools__status[data-state="success"] { color: #245b42; }
.study-tools__status[data-state="warning"] { color: var(--accent-dark); }
.annotation-editor { margin-top: 1rem; padding-top: 1rem; border-top: 1px solid var(--rule); }
.annotation-editor[hidden] { display: none; }
.annotation-editor label { display: block; margin-bottom: .4rem; font: 700 .82rem/1.3 var(--sans); }
.annotation-editor textarea {
  display: block;
  width: 100%;
  min-height: 5rem;
  padding: .65rem;
  border: 1px solid var(--rule);
  background: #fff;
  color: var(--ink);
  font: .98rem/1.45 var(--serif);
  resize: vertical;
}
.study-tools__privacy { margin: .85rem 0 0; color: var(--muted); font: .78rem/1.45 var(--sans); }
.study-highlight { padding: 0 .1em; background: #f4dda0; }
.study-underline { text-decoration: underline .13em #8d3f2f; text-underline-offset: .16em; }
.study-note { padding: 0 .1em; background: #d9e5e5; border-bottom: .12em dotted #2b6f8a; }
.study-note[title] { cursor: help; }
.study-highlight[data-study-id], .study-underline[data-study-id], .study-note[data-study-id] { cursor: pointer; }
.study-focus-mark { outline: 3px solid var(--accent); outline-offset: 3px; }
.mark-blue { background: #cfe3ef; }
.mark-pink { background: #f2d7df; }
.selection-tools {
  position: fixed;
  z-index: 20;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .35rem;
  max-width: min(32rem, calc(100vw - 1.5rem));
  padding: .5rem;
  border: 1px solid var(--ink);
  background: #fffdf8;
  box-shadow: 0 .45rem 1.5rem rgba(32, 37, 43, .18);
}
.selection-tools[hidden] { display: none; }
.selection-count { margin: 0 .25rem; color: var(--muted); font: .76rem/1.2 var(--sans); }
.study-tool-button--primary { background: var(--ink); color: var(--paper); }
.study-tool-button--danger { border-color: var(--accent); color: var(--accent-dark); }
.study-tool-button--dismiss { min-width: 2rem; padding-inline: .45rem; border: 0; background: transparent; }
.annotation-dialog {
  width: min(34rem, calc(100vw - 2rem));
  padding: 0;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink);
  box-shadow: 0 1rem 3rem rgba(32, 37, 43, .25);
}
.annotation-dialog::backdrop { background: rgba(32, 37, 43, .36); }
.annotation-dialog[hidden] { display: none; }
.annotation-dialog > header, .annotation-dialog > footer, .notes-panel > header { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1rem 1.25rem; border-bottom: 1px solid var(--rule); }
.annotation-dialog > header h2, .notes-panel > header h2 { margin: 0; font-size: 1.2rem; }
.annotation-dialog__body { padding: 1rem 1.25rem; }
.annotation-dialog blockquote { margin: 0 0 1rem; padding: .75rem 1rem; border-left: .25rem solid var(--accent); background: var(--paper-deep); }
.annotation-dialog label, .color-options legend, .panel-bottom label { font: 700 .82rem/1.3 var(--sans); }
.annotation-dialog label span { color: var(--muted); font-weight: 400; }
.annotation-dialog textarea { display: block; width: 100%; min-height: 6rem; margin-top: .4rem; padding: .65rem; border: 1px solid var(--rule); background: white; color: var(--ink); font: 1rem/1.45 var(--serif); resize: vertical; }
.color-options { display: flex; flex-wrap: wrap; gap: .6rem 1rem; margin: 1rem 0 0; padding: .7rem; border: 1px solid var(--rule); font: .84rem/1.3 var(--sans); }
.color-options legend { padding: 0 .3rem; }
.annotation-dialog > footer { justify-content: flex-end; border-top: 1px solid var(--rule); border-bottom: 0; }
.notes-panel {
  position: fixed;
  z-index: 19;
  top: 0;
  right: 0;
  display: flex;
  flex-direction: column;
  width: min(28rem, 100vw);
  height: 100vh;
  border-left: 1px solid var(--rule);
  background: var(--paper);
  box-shadow: -1rem 0 3rem rgba(32, 37, 43, .2);
}
.notes-panel[hidden] { display: none; }
.notes-open { overflow: hidden; }
.notes-panel > header { flex: 0 0 auto; }
.notes-panel .panel-help { flex: 0 0 auto; margin: 1rem 1.25rem; color: var(--muted); font: .84rem/1.5 var(--sans); }
.note-list { flex: 1 1 auto; overflow-y: auto; padding: 0 1.25rem 1rem; }
.note-card { margin: 0 0 1rem; padding: .85rem; border: 1px solid var(--rule); background: #fffdf8; }
.note-card__type { margin: 0 0 .4rem; color: var(--accent-dark); font: 700 .76rem/1.2 var(--sans); text-transform: uppercase; letter-spacing: .06em; }
.note-card blockquote { margin: 0; padding-left: .75rem; border-left: .2rem solid var(--highlight); font-size: .94rem; }
.note-card__text { margin: .65rem 0 0; padding-top: .65rem; border-top: 1px solid var(--rule); font-size: .9rem; }
.note-card__actions { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .75rem; }
.note-card__actions .study-tool-button { font-size: .75rem; }
.empty-state { color: var(--muted); font: .88rem/1.5 var(--sans); }
.note-card__meta { margin: 0 0 .5rem; color: var(--muted); font: .75rem/1.45 var(--sans); }
.note-card--unmatched { border-color: var(--accent); }
.panel-bottom { flex: 0 0 auto; display: grid; grid-template-columns: 1fr auto; gap: .5rem; padding: 1rem 1.25rem; border-top: 1px solid var(--rule); }
.panel-bottom label { grid-column: 1 / -1; }
.panel-bottom select { min-width: 0; padding: .5rem; border: 1px solid var(--rule); background: white; color: var(--ink); font: .8rem var(--sans); }
.panel-bottom .study-tool-button { font-size: .76rem; }

.concept-figure { margin: 2rem 0; padding: 1rem; border: 1px solid var(--rule); background: #fbfaf6; }
.concept-figure__graphic { max-width: 100%; overflow-x: auto; scroll-padding-inline: 1rem; }
.concept-figure img, .concept-figure svg { display: block; width: 100%; height: auto; max-height: 22rem; }
.concept-figure__graphic svg text { font-size: var(--diagram-text-size) !important; }
.concept-figure__graphic svg .title,
.concept-figure__graphic svg .h { font-size: calc(var(--diagram-text-size) + .14rem) !important; }
.concept-figure__graphic svg .small,
.concept-figure__graphic svg .s,
.concept-figure__graphic svg .sub { font-size: calc(var(--diagram-text-size) - .12rem) !important; }
.concept-figure__graphic svg .label,
.concept-figure__graphic svg .text,
.concept-figure__graphic svg .t { font-size: var(--diagram-text-size) !important; }
.concept-figure__alternative { margin-top: 1rem; padding-top: .8rem; border-top: 1px solid var(--rule); }
.concept-figure__alternative h3 { margin: 0 0 .5rem; font-size: 1rem; }
.concept-figure__alternative table { min-width: 0; }
.concept-figure__labels { columns: 2; column-gap: 2rem; padding-left: 1.4rem; }
.concept-figure__labels li { break-inside: avoid; margin-bottom: .25rem; }
.figure-caption { margin: .8rem 0 0; color: var(--muted); font: .84rem/1.5 var(--sans); }
.table-wrap { max-width: 100%; margin: 1.25rem 0; overflow-x: auto; border: 1px solid var(--rule); }
table { width: 100%; min-width: 38rem; border-collapse: collapse; font-size: .92em; }
caption { padding: .75rem; text-align: left; font: 700 .84rem var(--sans); }
th, td { padding: .7rem .8rem; border-top: 1px solid var(--rule); vertical-align: top; text-align: left; }
th { background: var(--paper-deep); font-family: var(--sans); }

.task-box { margin: 2rem 0; padding: 1.25rem; border: 2px solid var(--ink); background: #fffdf8; }
.task-box h2 { margin-top: 0; font-size: 1.35rem; }
.task-box__tag { margin: 0 0 .4rem; font: 700 .76rem var(--sans); letter-spacing: .08em; text-transform: uppercase; }
.task-box ol { padding-left: 1.25rem; }
.page-nav { display: flex; justify-content: space-between; gap: 1rem; margin-top: 4rem; padding-top: 1rem; border-top: 1px solid var(--rule); font: 700 .9rem var(--sans); }
.page-nav a:last-child { text-align: right; }
.site-footer { padding: 1.25rem; border-top: 1px solid var(--rule); color: var(--muted); text-align: center; font: .75rem var(--sans); }
.print-notes { display: none; }

@media (max-width: 900px) {
  .site-header__inner, .page-shell { width: min(100% - 1.25rem, var(--measure)); }
  .site-header__inner { display: block; }
  .course-label { display: block; margin-top: .35rem; }
  .page-shell { display: block; padding-top: 1.5rem; }
  .local-nav { position: static; margin-bottom: 2rem; padding-bottom: 1rem; border-bottom: 1px solid var(--rule); }
  .local-nav-toggle { display: inline-flex; }
  .local-nav.is-collapsed ol { display: none; }
  .font-tools { margin-top: 1rem; }
  .learning-map { grid-template-columns: 1fr; }
  .study-tools__row { align-items: stretch; }
  .study-tools__row .study-tool-button { flex: 1 1 9rem; }
  h1 { font-size: clamp(2.4rem, 15vw, 4rem); }
  .page-nav { align-items: stretch; flex-direction: column; }
  .page-nav a:last-child { text-align: left; }
  .concept-figure img, .concept-figure svg { width: 760px; max-width: none; max-height: none; }
  .concept-figure__labels { columns: 1; }
}

@page { size: A4; margin: 14mm 15mm; }

@media print {
  :root { --diagram-text-size: 10pt; }
  body { background: white; color: black; font-size: 11pt; }
  .skip-link, .site-header, .local-nav, .page-nav, .site-footer, .study-tools, .selection-tools, .notes-panel, .annotation-dialog { display: none !important; }
  .page-shell { display: block; width: auto; padding: 0; }
  main { max-width: none; }
  h1 { max-width: none; font-size: 26pt; letter-spacing: -.02em; }
  h2 { font-size: 16pt; }
  h3 { font-size: 12pt; }
  .dek { font-size: 13pt; }
  .learning-map { grid-template-columns: 1fr; }
  .task-box { break-inside: avoid; background: white; }
  a { color: black; text-decoration: none; }
  .table-wrap { overflow: visible; }
  table { min-width: 0; font-size: 9pt; }
  #concept-architecture > h2 { break-after: avoid-page; page-break-after: avoid; }
  .concept-figure { break-inside: avoid; }
  .concept-figure__graphic { overflow: visible; }
  .concept-figure img, .concept-figure svg { width: 100% !important; max-width: 100% !important; height: auto; max-height: none; }
  .reading-body { column-count: 1; max-width: none; }
  .study-note, .study-highlight { background: transparent; }
  .print-notes { display: block; margin-top: 2rem; border-top: 2px solid #000; }
  .print-notes article { break-inside: avoid; padding: .75rem 0; border-top: 1px solid #aaa; }
  .print-notes blockquote { margin: .5rem 0; }
}