/* A quiet reading surface: ink, white paper, and a restrained teal accent. */
:root {
  color-scheme: light;
  --ink: #172f3c;
  --body: #263c47;
  --muted: #566872;
  --line: #dbe2e5;
  --surface: #f4f7f8;
  --accent: #06665d;
  --accent-light: #e9f5f1;
  --focus: #b04705;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --serif: Charter, "Bitstream Charter", "Iowan Old Style", "Palatino Linotype", Georgia, serif;
}
* { box-sizing: border-box; }
html { scroll-padding-top: 100px; }
body { margin: 0; color: var(--body); background: #fff; font: 1rem/1.55 var(--sans); }
a { color: var(--accent); text-underline-offset: .2em; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 4px; border-radius: 3px; }
h1, h2, h3, p { margin: 0; }
h1, h2, h3 { color: var(--ink); }
h1 { font-size: clamp(2rem, 3.6vw, 2.75rem); line-height: 1.14; letter-spacing: -.035em; font-weight: 720; }
h2 { font-size: 1.55rem; line-height: 1.3; letter-spacing: -.025em; }
h3 { font-size: 1.1rem; line-height: 1.4; }
ul { padding-left: 1.3em; }
li + li { margin-top: .4em; }
.skip-link { position: fixed; left: 16px; top: -70px; z-index: 20; background: white; padding: 12px 18px; }
.skip-link:focus { top: 12px; }
.topbar { position: sticky; z-index: 10; top: 0; min-height: 84px; padding: 16px 4%; background: rgba(255,255,255,.98); border-bottom: 1px solid var(--line); display: flex; align-items: center; gap: 30px; }
.primary-nav { display: flex; gap: 6px; margin: 0 auto; }
.primary-nav a { color: var(--muted); padding: 10px 15px; border-radius: 6px; text-decoration: none; font-size: .9375rem; }
.primary-nav a:hover { background: var(--surface); color: var(--ink); }
.primary-nav a[aria-current="page"] { background: var(--accent-light); color: var(--accent); font-weight: 650; }
.reader-layout { max-width: 1300px; margin: auto; display: grid; grid-template-columns: 245px minmax(0, 1fr); gap: clamp(32px, 5vw, 80px); padding: 42px 4% 80px; }
.reading-sidebar { position: sticky; top: 125px; align-self: start; max-height: calc(100vh - 160px); overflow-y: auto; padding: 2px 6px 20px 1px; }
.eyebrow { font-size: .75rem; font-weight: 720; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.toc-title { margin: 18px 0 7px; font-size: .9375rem; font-weight: 650; }
.toc { list-style: none; padding: 0; margin: 0; }
.toc li + li { margin: 3px 0 0; }
.toc a { display: block; border-left: 2px solid var(--line); padding: 8px 12px; font-size: .875rem; line-height: 1.4; color: var(--muted); text-decoration: none; }
.toc a:hover { color: var(--ink); background: var(--surface); }
.toc a[aria-current="location"] { border-color: var(--accent); color: var(--accent); background: var(--accent-light); }
.sidebar-footer { margin-top: 28px; padding-top: 20px; border-top: 1px solid var(--line); }
.sidebar-footer p { font-size: .875rem; margin-bottom: 12px; }
.sidebar-footer a { font-size: .875rem; font-weight: 600; }
.mobile-toc { display: none; }
.reading-main { width: 100%; max-width: 760px; min-width: 0; }
.module-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-bottom: 17px; }
.status { display: inline-block; font-size: .8125rem; padding: 3px 9px; border-radius: 4px; color: var(--muted); background: var(--surface); white-space: nowrap; }
.status.draft, .status.reviewed { color: var(--accent); background: var(--accent-light); }
.module-subtitle { margin-top: 17px; max-width: 650px; font-size: 1.125rem; line-height: 1.55; color: var(--muted); }
.layer-switch { position: relative; isolation: isolate; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0; margin: 27px 0 24px; padding: 5px; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); width: min(100%, 370px); }
.layer-switch a { position: relative; z-index: 1; text-align: center; text-decoration: none; color: var(--muted); padding: 9px 22px; border-radius: 5px; font-size: .9375rem; font-weight: 600; }
.layer-switch a[aria-current="page"] { color: white; background: transparent; }
.layer-switch a:hover:not([aria-current="page"]) { color: var(--ink); }
.objectives { border-bottom: 1px solid var(--line); padding: 0 0 23px; margin-bottom: 38px; font-size: .9375rem; }
.objectives summary, .mobile-toc summary { color: var(--ink); font-weight: 650; cursor: pointer; padding: 7px 0; }
.objectives ul { margin: 13px 0; }
.objectives p { color: var(--muted); }
.reading-section { scroll-margin-top: 24px; margin-bottom: 44px; }
.reading-section > h2 { margin: 0 0 21px; }
.block { margin: 0 0 23px; }
.prose { font: 1.1875rem/1.78 var(--serif); color: var(--body); }
.prose p + p { margin-top: 1em; }
.prose ul { margin: 0; }
.block-refs { display: flex; align-items: baseline; gap: 6px; flex-wrap: wrap; margin-top: 6px; font: .75rem/1.4 var(--sans); color: var(--muted); }
.block-refs a { color: var(--muted); text-decoration: none; border-bottom: 1px dotted #7d8a91; padding: 3px 1px; }
.block-refs a:hover { color: var(--accent); }
.callout { padding: 21px 23px; border-left: 3px solid #b9cbd2; background: var(--surface); border-radius: 0 7px 7px 0; }
.callout.key { background: var(--accent-light); border-color: var(--accent); }
.callout.precision { background: #fff7e9; border-color: #b96d08; }
.callout h3 { margin-bottom: 8px; font-size: .9375rem; }
.callout p { font-size: 1.0625rem; line-height: 1.7; }
.figure-caption { display: block; color: var(--ink); font-size: .875rem; line-height: 1.5; font-weight: 650; margin-bottom: 11px; }
.table-scroll { max-width: 100%; overflow-x: auto; border: 1px solid var(--line); border-radius: 7px; }
table { width: 100%; border-collapse: collapse; text-align: left; font-size: .9375rem; line-height: 1.6; }
th { color: var(--ink); background: #eef3f5; font-size: .8125rem; font-weight: 650; }
th, td { padding: 14px 16px; vertical-align: top; border-bottom: 1px solid var(--line); }
tr:last-child td { border-bottom: 0; }
td:first-child { color: var(--ink); font-weight: 550; }
table.wide-table { min-width: 620px; }
.table-hint { font-size: .8125rem; color: var(--muted); margin-top: 6px; }
pre { border-radius: 8px; background: #152c38; color: #edf4f6; padding: 24px; overflow-x: auto; font: .875rem/1.9 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; tab-size: 4; margin: 0; }
.checkpoint { border: 1px solid #acc9c2; border-radius: 8px; padding: 25px; }
.checkpoint .eyebrow { color: var(--accent); margin-bottom: 11px; }
.checkpoint-prompt { color: var(--ink); font-size: 1.125rem; line-height: 1.6; }
.checkpoint details { margin-top: 16px; }
.checkpoint summary { cursor: pointer; font-size: .9375rem; color: var(--accent); font-weight: 650; padding: 8px 0; }
.checkpoint .hint { color: var(--muted); font-size: .9375rem; margin-top: 10px; }
.checkpoint .answer { border-top: 1px solid var(--line); margin-top: 9px; padding-top: 17px; }
.checkpoint .answer .block:last-child { margin-bottom: 0; }
.sources { padding-top: 30px; border-top: 1px solid var(--line); }
.sources h2 { margin-bottom: 20px; }
.source-list { padding-left: 25px; font-size: .875rem; }
.source-list li { padding: 5px 0 8px 7px; scroll-margin-top: 110px; }
.source-list p { color: var(--muted); font-size: .8125rem; margin-top: 4px; }
.course-note { color: var(--muted); font-size: .875rem; margin: 25px 0; padding: 17px 0; border-top: 1px solid var(--line); }
.reading-next { padding: 23px; background: var(--accent-light); border-radius: 8px; display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 36px; }
.reading-next p { font-size: .9375rem; color: var(--accent); }
.reading-next h3 { margin-bottom: 5px; }
.button { display: inline-flex; align-items: center; justify-content: center; text-decoration: none; border: 1px solid transparent; border-radius: 6px; background: var(--ink); color: white; font-size: .9375rem; font-weight: 650; padding: 12px 18px; line-height: 1.4; text-align: center; }
.button:hover { background: #254a59; }
.button.secondary { border-color: #bdcbd1; color: var(--ink); background: white; }
.button.secondary:hover { background: var(--surface); }
.module-pagination { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--line); padding-top: 24px; gap: 24px; margin-top: 34px; }
.module-pagination a { text-decoration: none; color: var(--ink); font-size: .9375rem; }
.module-pagination .next { text-align: right; }
.module-pagination small { display: block; color: var(--muted); margin-bottom: 6px; font-size: .8125rem; }
.module-pagination .status { margin-top: 9px; }
.page { max-width: 1120px; padding: 48px 32px 90px; margin: auto; }
.page-header { margin-bottom: 34px; max-width: 760px; }
.page-header .eyebrow { margin-bottom: 14px; }
.page-header p { color: var(--muted); margin-top: 16px; font-size: 1.0625rem; }
.available-module { border-left: 4px solid var(--accent); background: var(--accent-light); border-radius: 0 8px 8px 0; padding: 25px 28px; margin-bottom: 44px; display: grid; grid-template-columns: 1fr auto; gap: 24px; align-items: center; }
.available-module h2 { margin: 9px 0; font-size: 1.55rem; }
.available-module p { max-width: 640px; color: #31594f; font-size: .9375rem; }
.track + .track { margin-top: 39px; }
.track > h2 { margin-bottom: 18px; font-size: 1.25rem; }
.module-list { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--line); }
.module-list li { margin: 0; }
.module-row { padding: 22px 0; display: grid; grid-template-columns: 35px minmax(0, 1fr) auto; gap: 18px; align-items: start; border-bottom: 1px solid var(--line); text-decoration: none; color: var(--ink); }
.module-row:hover h3 { color: var(--accent); text-decoration: underline; text-underline-offset: 4px; }
.module-number { color: #6e808a; font-size: .9375rem; font-variant-numeric: tabular-nums; padding-top: 2px; }
.module-row p { margin-top: 6px; color: var(--muted); font-size: .9375rem; }
.module-row .question-tag { color: var(--accent); font-size: .8125rem; }
.page-note { margin-top: 35px; padding-top: 23px; border-top: 1px solid var(--line); color: var(--muted); font-size: .875rem; }
.tde-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.tde-card { border: 1px solid var(--line); padding: 25px; border-radius: 8px; display: flex; flex-direction: column; align-items: start; }
.tde-card.available { border-color: #96bcb2; }
.tde-card .eyebrow { margin-bottom: 12px; color: var(--accent); }
.tde-card h2 { font-size: 1.2rem; letter-spacing: -.015em; }
.tde-card p { margin-top: 12px; font-size: .9375rem; color: var(--muted); }
.tde-card .locator { margin-bottom: 20px; font-size: .8125rem; }
.tde-card a { margin-top: auto; font-size: .9375rem; font-weight: 650; }
.planned-page { max-width: 800px; }
.planned-page .planned-objectives { background: var(--surface); padding: 27px 30px; border-radius: 8px; margin: 30px 0; }
.planned-page .planned-objectives h2 { font-size: 1.15rem; margin-bottom: 12px; }
.planned-page .planned-objectives li { margin-top: 10px; }
.planned-page .actions { display: flex; flex-wrap: wrap; gap: 12px; }
.loading-state, .error-state { max-width: 680px; padding: 60px 24px; margin: auto; }
.error-state p { margin: 20px 0; }
.noscript { padding: 30px; }
@media (min-width: 1100px) { .table-hint { display: none; } }
@media (max-width: 900px) {
  .reader-layout { grid-template-columns: 190px minmax(0, 1fr); gap: 30px; padding: 32px 28px 60px; }
  .reading-sidebar { top: 114px; }
  .topbar { padding: 14px 24px; gap: 15px; }
  .primary-nav a { padding: 10px 12px; }
  .beta-label { display: none; }
  .available-module { grid-template-columns: 1fr; gap: 20px; }
  .available-module .button { justify-self: start; }
}
@media (max-width: 680px) {
  html { scroll-padding-top: 95px; }
  .topbar { min-height: 74px; padding: 12px 16px; gap: 10px; }
  .brand-symbol { width: 36px; height: 36px; border-radius: 7px; font-size: .9375rem; }
  .brand-name { display: none; }
  .primary-nav { margin-left: auto; margin-right: 0; gap: 2px; }
  .primary-nav a { padding: 9px 10px; font-size: .875rem; }
  .reader-layout { display: block; padding: 28px 20px 50px; }
  .reading-sidebar { display: none; }
  .mobile-toc { display: block; border: 1px solid var(--line); border-radius: 7px; padding: 7px 15px; margin: 0 0 27px; font-size: .9375rem; }
  .mobile-toc .toc { padding-bottom: 9px; }
  h1 { font-size: 2.05rem; }
  h2 { font-size: 1.4rem; }
  .module-subtitle { font-size: 1.0625rem; }
  .module-meta { gap: 8px; margin-bottom: 16px; }
  .module-meta .eyebrow { font-size: .75rem; }
  .layer-switch { width: 100%; margin-top: 24px; }
  .layer-switch a { padding: 9px 10px; flex: 1; text-align: center; }
  .prose { font-size: 1.125rem; line-height: 1.8; }
  .reading-section { margin-bottom: 37px; }
  .callout { padding: 18px; }
  th, td { padding: 12px; }
  .checkpoint { padding: 20px; }
  pre { padding: 18px; }
  .reading-next { display: block; padding: 21px; }
  .reading-next .button { margin-top: 18px; }
  .page { padding: 33px 20px 60px; }
  .page-header { margin-bottom: 27px; }
  .available-module { padding: 22px; margin-bottom: 32px; }
  .available-module h2 { font-size: 1.4rem; }
  .module-row { grid-template-columns: 26px 1fr; gap: 12px; padding: 20px 0; }
  .module-row > .status { grid-column: 2; justify-self: start; margin-top: 0; }
  .tde-grid { grid-template-columns: 1fr; gap: 14px; }
  .tde-card { padding: 22px; }
  .module-pagination { gap: 15px; }
  .planned-page .planned-objectives { padding: 22px; }
}
@media (prefers-reduced-motion: no-preference) { a, button { transition: background-color .12s, color .12s; } }
@media print {
  .topbar, .reading-sidebar, .mobile-toc, .layer-switch, .module-pagination, .reading-next, .skip-link { display: none; }
  .reader-layout, .page { display: block; padding: 0; }
  .reading-main { max-width: none; }
  .table-scroll, pre { overflow: visible; }
  .checkpoint, .callout, tr { break-inside: avoid; }
  body, .prose { font-size: 11pt; }
}

/* Orientation and self-reported study progress. */
.breadcrumbs { display: flex; flex-wrap: wrap; gap: 9px; color: var(--muted); font-size: .875rem; margin-bottom: 24px; }
.breadcrumbs a { text-decoration: none; }
.step-label, .question-label { font-size: .875rem; line-height: 1.5; }
.step-label { color: var(--muted); padding-right: 12px; border-right: 1px solid var(--line); }
.question-label { color: var(--accent); }
.progress-overview { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; padding: 22px 0 28px; border-top: 1px solid var(--line); margin-bottom: 20px; }
.progress-overview p, .tde-progress-total { color: var(--ink); font-weight: 650; margin-bottom: 10px; }
.study-progress-bar { height: 14px; border-radius: 999px; overflow: hidden; background: #e4ecee; }
.progress-fill { display: block; width: 100%; height: 100%; background: var(--accent); transform-origin: left center; transition: transform 450ms cubic-bezier(.22, 1, .36, 1); }
@media (prefers-reduced-motion: reduce) { .progress-fill { transition: none; } }
.progress-note { font-size: .875rem; color: var(--muted); margin: 0 0 30px; max-width: 760px; }
.progress-toggle { display: inline-flex; align-items: center; gap: 9px; min-height: 44px; font-size: .875rem; cursor: pointer; color: var(--body); }
.progress-toggle input { width: 19px; height: 19px; margin: 0; accent-color: var(--accent); flex: 0 0 auto; }
.progress-toggle:has(input:checked) { color: var(--accent); font-weight: 650; }
.study-method { margin: 0 0 44px; }
.study-method > h2 { font-size: 1.25rem; margin-bottom: 22px; }
.study-method ol { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 30px; padding: 0; list-style-position: inside; counter-reset: study-method; }
.study-method li { list-style: none; border-top: 2px solid var(--line); padding-top: 14px; margin: 0; }
.study-method h3 { font-size: 1rem; margin-bottom: 8px; }
.study-method h3::before { counter-increment: study-method; content: counter(study-method) '. '; color: var(--accent); }
.study-method p { font-size: .9375rem; color: var(--muted); }
.track-note { color: var(--muted); font-size: .9375rem; margin: 10px 0 20px; }
.module-row h3 a { color: var(--ink); text-decoration: none; }
.module-row h3 a:hover { text-decoration: underline; }
.module-list > li { padding-bottom: 0; }
.topic-state { display: flex; flex-direction: column; align-items: flex-end; gap: 9px; }
.topic-questions { margin: 0 0 24px 53px; padding: 16px 20px; background: var(--surface); border-radius: 0 0 8px 8px; }
.topic-questions h4 { margin: 0 0 10px; color: var(--muted); font-size: .875rem; font-weight: 650; }
.question-progress-row { display: flex; gap: 18px; align-items: center; flex-wrap: wrap; margin-top: 2px; }
.question-progress-row > a { font-size: .875rem; min-width: 136px; }
.reader-progress { border-top: 1px solid var(--line); padding-top: 16px; margin-bottom: 36px; }
.reader-progress p { font-size: .875rem; color: var(--muted); }
.reader-progress .progress-note { margin: 10px 0 0; }
.course-question-links { padding-left: 22px; }
.course-question-links a { line-height: 1.6; }
.tde-card h2 a { font-size: 1.2rem; color: var(--ink); text-decoration: none; }
.tde-card h2 a:hover { text-decoration: underline; }
.tde-card .question-open { margin: auto 0 13px; }
.tde-progress-total { margin-bottom: 22px; }
.tde-grid + .progress-note { margin-top: 28px; }
.question-page { max-width: 840px; }
.question-statement { border-left: 3px solid var(--accent); background: var(--surface); padding: 24px 28px; border-radius: 0 8px 8px 0; }
.question-statement h2 { font-size: 1rem; margin-bottom: 14px; }
.question-statement .locator { font-size: .8125rem; color: var(--muted); margin-top: 18px; }
.try-first { margin: 24px 0 15px; color: var(--muted); font-size: .9375rem; }
.possible-answer { border: 1px solid #acc9c2; border-radius: 8px; margin-bottom: 16px; }
.possible-answer summary { padding: 18px 22px; color: var(--accent); font-weight: 650; cursor: pointer; }
.possible-answer .answer { padding: 0 22px 22px; }
.possible-answer .prose { margin: 15px 0; }
.answer-note, .answer-pending { font-size: .875rem; color: var(--muted); }
.answer-pending { padding: 20px; background: var(--surface); margin: 16px 0; }
.answer-sources { display: flex; flex-direction: column; gap: 9px; font-size: .8125rem; }
.question-study { margin: 30px 0; padding-top: 26px; border-top: 1px solid var(--line); }
.question-study h2 { font-size: 1.25rem; margin-bottom: 14px; }
.question-study h3 { font-size: 1rem; margin-bottom: 10px; }
.question-study .actions { display: flex; flex-wrap: wrap; gap: 20px; }
.question-page > .progress-note { margin-top: 28px; }
@media (max-width: 680px) {
  html { scroll-padding-top: 145px; }
  .topbar { display: grid; grid-template-columns: 1fr; gap: 8px; padding: 10px 16px; }
  .brand { justify-self: start; }
  .brand-name { display: block; }
  .brand-name br { display: none; }
  .primary-nav { margin: 0; width: 100%; display: flex; flex-wrap: wrap; gap: 3px; }
  .primary-nav a { text-align: center; padding: 8px 7px; font-size: .875rem; }
  .primary-nav a { flex: 1 0 auto; }
  .study-method ol { grid-template-columns: 1fr; gap: 17px; }
  .progress-overview { gap: 18px; }
  .progress-overview p { font-size: .875rem; }
  .topic-state { grid-column: 2; align-items: flex-start; }
  .topic-questions { margin-left: 0; padding: 16px; }
  .question-progress-row { gap: 4px 12px; }
  .question-progress-row > a { min-width: 125px; }
  .question-statement { padding: 20px; }
  .module-meta { gap: 10px 12px; }
  .step-label { border: 0; }
}
@media print {
  .breadcrumbs, .progress-toggle, .reader-progress, .progress-note { display: none; }
}

.home-page .page-header { max-width: 790px; }
.page-header .welcome-signoff { color: var(--accent); font-weight: 600; }
.question-context { margin: 20px 0; border: 1px solid var(--line); border-radius: 8px; }
.question-context > summary { padding: 18px 22px; cursor: pointer; font-weight: 650; color: var(--ink); }
.context-body { padding: 0 22px 4px; }
.context-note { font-size: .875rem; color: var(--muted); margin-bottom: 22px; }
.context-section { margin: 0 0 26px; }
.context-section h3 { margin-bottom: 5px; }
.context-section .locator { font-size: .8125rem; color: var(--muted); margin-bottom: 14px; }
.source-excerpt { margin: 0; }
.source-excerpt .prose { font-size: 1.0625rem; }
.source-excerpt .block:last-child { margin-bottom: 0; }
.stage-navigation { margin-top: 10px; }
.stage-section { margin-bottom: 8px; border: 1px solid var(--line); border-radius: 7px; }
.stage-section > summary { padding: 12px; color: var(--ink); cursor: pointer; font-size: .875rem; line-height: 1.5; }
.stage-number { color: var(--muted); font-size: .8125rem; }
.stage-title { display: block; font-weight: 650; margin-top: 3px; }
.stage-section[open] > summary { background: var(--accent-light); border-radius: 6px 6px 0 0; }
.stage-content { padding: 8px; }
.stage-layers { display: flex; flex-wrap: wrap; gap: 6px; padding: 3px 0 12px; }
.stage-layers a { padding: 5px 7px; font-size: .8125rem; border-radius: 4px; text-decoration: none; }
.stage-layers a[aria-current="page"] { background: var(--ink); color: white; }
.stage-content .toc a { font-size: .8125rem; padding: 8px; }
.mobile-toc .stage-section > summary { padding: 12px; }
@media (max-width: 680px) {
  .context-body { padding-left: 16px; padding-right: 16px; }
  .question-context > summary { padding: 16px; }
  .question-progress-row { justify-content: space-between; }
}

.module-meta > * { display: inline-flex; align-items: center; min-height: 28px; margin: 0; line-height: 1.4; }
.module-meta .status { font-size: .875rem; }
.available-module .availability-note { margin-top: 13px; font-size: .8125rem; color: var(--muted); }
.question-study > h2 { font-size: 1rem; margin-bottom: 14px; color: var(--muted); }
.related-theme { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 22px; padding: 22px; border: 1px solid var(--line); border-radius: 8px; }
.related-theme + .related-theme { margin-top: 14px; }
.related-theme-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 10px; font-size: .8125rem; color: var(--muted); }
.related-theme-description h3 { font-size: 1.0625rem; margin-bottom: 7px; }
.related-theme-description p { font-size: .9375rem; color: var(--muted); }
.related-theme-actions { display: flex; flex-direction: column; gap: 8px; align-items: stretch; }
.mock-exam-page { max-width: 820px; }
.mock-exam-status { margin: 0 0 24px; color: var(--muted); }
.mock-exam-page .actions { display: flex; gap: 12px; flex-wrap: wrap; }
@media (max-width: 680px) {
  html { scroll-padding-top: 175px; }
  .related-theme { grid-template-columns: minmax(0, 1fr); gap: 18px; padding: 18px; }
  .related-theme-actions { flex-direction: row; flex-wrap: wrap; }
  .related-theme-actions a { flex: 1 1 auto; }
}

/* Keep the reading shell stable while the selector slides between layers. */
.layer-switch::before { content: ''; position: absolute; z-index: 0; top: 5px; bottom: 5px; left: 5px; width: calc((100% - 10px) / 2); border-radius: 5px; background: var(--ink); transition: transform 260ms cubic-bezier(.22, 1, .36, 1); }
.layer-switch[data-layer="deep"]::before { transform: translateX(100%); }
.reader-panels { overflow-anchor: none; }
.checkpoint { padding: 21px 23px; }
.checkpoint .eyebrow { margin-bottom: 8px; }
.checkpoint-prompt { font-size: 1.0625rem; line-height: 1.65; }
.checkpoint-controls { margin-top: 12px; }
.checkpoint-controls details { margin-top: 0; }
.checkpoint-controls summary { padding: 7px 0; min-height: 38px; }
.checkpoint-controls .hint { margin: 5px 0 12px; padding-left: 16px; border-left: 2px solid var(--line); }
.checkpoint-controls .answer { margin-top: 4px; padding-top: 14px; }
.checkpoint > .block-refs { border-top: 1px solid var(--line); padding-top: 9px; margin-top: 10px; }
.reader-progress, .question-progress { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 6px 18px; }
.reader-progress .progress-note, .question-progress .progress-note { margin: 0; font-size: .8125rem; }
.question-progress { margin-top: 12px; }
@supports (interpolate-size: allow-keywords) and selector(::details-content) {
  details { interpolate-size: allow-keywords; }
  details::details-content { height: 0; overflow: clip; opacity: 0; transition: height 240ms ease, opacity 180ms ease, content-visibility 240ms allow-discrete; }
  details[open]::details-content { height: auto; opacity: 1; }
}
@media (prefers-reduced-motion: reduce) {
  .layer-switch::before, details::details-content { transition: none; }
}

.stage-section > summary { position: relative; padding-right: 2.3rem; }
.stage-check { position: absolute; right: .65rem; top: .7rem; display: grid; place-items: center; width: 1.3rem; height: 1.3rem; border-radius: 50%; background: #286354; color: white; font-size: .85rem; opacity: 0; transform: scale(.7); transition: opacity 200ms, transform 200ms; }
.stage-check[data-studied=true] { opacity: 1; transform: scale(1); }

/* Finishing pass: stable navigation, balanced type, and a quiet completion reward. */
html { scroll-padding-top: calc(var(--header-height, 84px) + 16px); }
h1, h2, h3, .stage-title, .checkpoint-prompt { text-wrap: balance; }
p, .exam-option-text, .exam-prompt { text-wrap: pretty; }
.reading-sidebar { top: calc(var(--header-height, 84px) + 30px); max-height: calc(100dvh - var(--header-height, 84px) - 55px); }
.reading-next .button { flex-shrink: 0; max-width: 100%; }
.layer-switch a { min-width: 0; }
.source-list a { overflow-wrap: anywhere; }
.study-progress-bar { isolation: isolate; position: relative; transition: box-shadow 300ms; }
.progress-fill { position: relative; overflow: hidden; }
.progress-lava { display: none; }
.study-progress-bar[data-complete="true"] { background: #ebc955; box-shadow: 0 0 9px #edcf6b50; }
.study-progress-bar[data-complete="true"] .progress-fill { background: linear-gradient(100deg, #ebc955, #f4d879 48%, #e7c34d); }
.study-progress-bar[data-complete="true"] .progress-lava {
  display: block; position: absolute; left: 0; top: -9px; width: 27%; height: 30px;
  border-radius: 44% 56% 65% 35% / 55% 38% 62% 45%;
  background: #d9b445; filter: blur(.8px); opacity: .9;
  animation: progress-lava-flow 6.6s ease-in-out -2s infinite alternate;
}
.study-progress-bar[data-complete="true"] .progress-lava:nth-child(2) { left: 18%; width: 22%; background: #f7df91; animation-duration: 7.8s; animation-delay: -5s; animation-direction: alternate-reverse; }
.study-progress-bar[data-complete="true"] .progress-lava:nth-child(3) { left: 39%; width: 30%; background: #e3c052; animation-duration: 5.9s; animation-delay: -1s; }
.study-progress-bar[data-complete="true"] .progress-lava:nth-child(4) { left: 62%; width: 23%; background: #f5dc82; animation-duration: 8.4s; animation-delay: -6s; animation-direction: alternate-reverse; }
.study-progress-bar[data-complete="true"] .progress-lava:nth-child(5) { left: 84%; width: 26%; background: #dcb748; animation-duration: 6.9s; animation-delay: -4s; }
@keyframes progress-lava-flow {
  0% { transform: translate(-35%, -28%) scale(.75, 1.05) rotate(-9deg); border-radius: 42% 58% 66% 34% / 62% 34% 66% 38%; }
  35% { transform: translate(4%, 24%) scale(1.25, .72) rotate(7deg); border-radius: 66% 34% 38% 62% / 32% 58% 42% 68%; }
  70% { transform: translate(25%, -8%) scale(.9, 1.2) rotate(-5deg); border-radius: 34% 66% 58% 42% / 56% 40% 60% 44%; }
  100% { transform: translate(48%, 32%) scale(1.3, .8) rotate(11deg); border-radius: 58% 42% 30% 70% / 42% 64% 36% 58%; }
}
@media (max-width: 680px) {
  .topbar { min-height: 64px; padding: 9px 12px; display: flex; }
  .primary-nav { display: grid; grid-template-columns: .9fr .95fr 1fr 1.6fr 1.2fr; gap: 2px; width: 100%; margin: 0; }
  .primary-nav a { padding: 11px 2px; min-height: 44px; font-size: clamp(.75rem, 3.2vw, .875rem); white-space: nowrap; display: flex; align-items: center; justify-content: center; }
  .layer-switch a { padding-inline: 4px; font-size: .875rem; }
  .module-pagination .status { white-space: normal; }
  .progress-overview { gap: 16px; }
  .progress-overview p { text-wrap: balance; }
  .reading-next { padding: 18px; }
  .table-scroll table { min-width: 400px; }
  .table-scroll table.wide-table { min-width: 620px; }
}
@media (max-width: 360px) {
  .page, .reader-layout { padding-left: 16px; padding-right: 16px; }
  h1 { font-size: 1.875rem; }
  .module-row { gap: 8px; }
  .checkpoint { padding: 17px; }
  .status { white-space: normal; }
}
@media (prefers-reduced-motion: reduce) {
  .study-progress-bar { transition: none; }
  .study-progress-bar[data-complete="true"] .progress-lava { animation: none; }
}

.product-name { color: var(--ink); text-decoration: none; font-size: 1.15rem; font-weight: 760; letter-spacing: -.035em; white-space: nowrap; line-height: 1.3; }
.product-name sup { font-size: .48em; letter-spacing: .01em; margin-left: 3px; vertical-align: super; }
@media (min-width: 1000px) { .topbar { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); } }
@media (max-width: 999px) {
  .topbar { display: flex; flex-direction: column; gap: 5px; padding-block: 10px; }
  .product-name { align-self: center; font-size: 1.075rem; }
}

.nav-mobile { display: none; }
@media (max-width: 680px) { .nav-mobile { display: inline; } .nav-desktop { display: none; } .primary-nav { grid-template-columns: .9fr .95fr 1fr 1.25fr 1.2fr; } }

/* The brand scrolls out naturally; only the mobile navigation stays pinned. */
@media (max-width: 680px) {
  .topbar { display: grid; grid-template-columns: minmax(0, 1fr); grid-template-rows: 28px 44px; gap: 12px; padding: 12px 12px 6px; min-height: 0; top: -52px; }
  .product-name { justify-self: center; align-self: center; }
  .primary-nav { gap: 6px; }
  .primary-nav a { position: relative; isolation: isolate; background: transparent; padding-block: 5px; }
  .primary-nav a:hover, .primary-nav a[aria-current="page"] { background: transparent; }
  .primary-nav a::before { content: ''; position: absolute; z-index: -1; inset: 6px 0; border-radius: 6px; background: transparent; transition: background-color .16s ease; }
  .primary-nav a:hover::before { background: var(--surface); }
  .primary-nav a[aria-current="page"]::before { background: var(--accent-light); }
}
@media (prefers-reduced-motion: reduce) { .primary-nav a::before { transition: none; } }