/* Reading-first documentation: quiet surfaces, clear hierarchy, comfortable controls. */
:root {
  --sl-font: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --sl-content-width: 56rem;
  --sl-text-body: 1rem;
  --sl-color-accent-low: #1c2b48;
  --sl-color-accent: #668ff0;
  --sl-color-accent-high: #b8ccff;
  --note-bg: #18191d;
  --note-surface: #202126;
  --note-muted-surface: #24252b;
  --note-border: #383a43;
  --note-text: #e8e9ed;
  --note-muted: #b4b7c2;
  --note-accent: #a9c2ff;
  --note-accent-soft: #242e46;
  --note-button: #a9c2ff;
  --note-on-button: #142344;
  --note-field-border: #7a8091;
  --note-focus: #a9c2ff;
  --sl-color-bg: var(--note-bg);
  --sl-color-bg-sidebar: var(--note-surface);
  --sl-color-hairline: var(--note-border);
  --note-radius: .75rem;
  --note-font-size: 16px;
}
[data-md-color-scheme="default"] {
  --sl-color-accent-low: #edf2ff;
  --sl-color-accent: #3564d5;
  --sl-color-accent-high: #244fba;
  --note-bg: #fafafa;
  --note-surface: #fff;
  --note-muted-surface: #f3f4f6;
  --note-border: #dfe2e8;
  --note-text: #242833;
  --note-muted: #555e70;
  --note-accent: #2859c5;
  --note-accent-soft: #edf2ff;
  --note-button: #2859c5;
  --note-on-button: #fff;
  --note-field-border: #7c8495;
  --note-focus: #2859c5;
}
body { line-height: 1.85; }
:where(button, a, select, input, summary) { touch-action: manipulation; }
:where(a, button, input, select, summary):focus-visible { outline: 3px solid var(--note-focus); outline-offset: 4px; }
:where(button, select, summary) { cursor: pointer; }
h1, h2, h3 { letter-spacing: -.025em; text-wrap: balance; }
h1#_top { font-size: clamp(1.85rem, 3vw, 2.65rem); line-height: 1.4; }
.md-typeset { color: var(--note-text); }
.md-typeset.chapter-prose { font-size: var(--note-font-size); line-height: 1.95; }
.md-typeset :is(p, li) { overflow-wrap: anywhere; }
.md-typeset.chapter-prose h2 { margin-top: 2.8rem; padding-top: 1rem; border-top: 1px solid var(--note-border); font-size: 1.45em; line-height: 1.55; }
.md-typeset.chapter-prose h3 { font-size: 1.15em; margin-top: 2rem; }
.md-typeset table { display: table; width: 100%; border-collapse: separate; border-spacing: 0; font-size: .9em; line-height: 1.8; margin-block: 1.25rem; }
.md-typeset th { background: var(--note-muted-surface); font-weight: 650; color: var(--note-text); }
.md-typeset :is(th, td) { padding: .8rem .9rem; border-bottom: 1px solid var(--note-border); vertical-align: top; }
.md-typeset tr:last-child td { border-bottom-width: 1px; }
.md-typeset blockquote { border-inline-start: 3px solid var(--note-accent); font-size: .875em; color: var(--note-muted); background: var(--note-muted-surface); padding: 1rem 1.15rem; border-radius: 0 .5rem .5rem 0; }
.md-typeset :not(pre) > code { border-radius: .25rem; font-size: .9em; }
.study-toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: .5rem 1rem; padding: .7rem 1rem; margin-bottom: 1.75rem; border: 1px solid var(--note-border); border-radius: var(--note-radius); font-size: .875rem; background: var(--note-surface); color: var(--note-text); }
.study-toolbar label { display: flex; align-items: center; gap: .6rem; min-height: 44px; cursor: pointer; }
input[type='checkbox'] { accent-color: var(--note-button); width: 1.1rem; height: 1.1rem; }
.study-toolbar .reading-size { margin-left: auto; }
.reading-size select { padding: .3rem .5rem; min-height: 44px; border: 1px solid var(--note-field-border); border-radius: .4rem; background: var(--note-surface); color: inherit; font: inherit; }
.lab-buttons button[type='reset'], .close-dialog { min-height: 44px; font: inherit; padding: .45rem .75rem; border: 1px solid var(--note-field-border); border-radius: .4rem; color: var(--note-text); background: var(--note-surface); transition: background .18s, border-color .18s; }
.lab-buttons button[type='reset']:hover, .close-dialog:hover { background: var(--note-accent-soft); border-color: var(--note-accent); }
.save-status { color: var(--note-muted); font-size: .8rem; }
.save-status:empty { display: none; }
.md-typeset details.exercise-answer { margin: 1rem 0 2rem; border: 1px solid var(--note-border); border-radius: .6rem; padding: 0 1rem; background: var(--note-surface); }
.exercise-answer summary { color: var(--note-accent); font-size: .925em; font-weight: 600; min-height: 48px; padding-block: .65rem; }
.exercise-answer[open] { padding-bottom: 1rem !important; }
.exercise-answer[open] summary { border-bottom: 1px solid var(--note-border); margin-bottom: 1rem; }
.figure-zoom { position: relative; display: block; width: 100%; border: 1px solid var(--note-border); padding: 1rem; border-radius: .6rem; background: white; cursor: zoom-in; margin-block: 1.75rem; overflow: hidden; }
.figure-zoom img { display: block; width: 100%; height: auto; margin: 0; }
.zoom-hint { position: absolute; right: .5rem; bottom: .5rem; padding: .15rem .5rem; background: #f1f4fa; color: #4c586f; font: 500 .75rem/1.6 var(--sl-font); border-radius: .25rem; }
.image-dialog { width: min(94vw, 1400px); max-width: 96vw; max-height: 94dvh; border: 1px solid var(--note-border); border-radius: var(--note-radius); padding: 1rem; background: var(--note-bg); color: var(--note-text); }
.image-dialog::backdrop { background: #071719d9; }
.image-dialog img { width: 100%; max-height: 76dvh; object-fit: contain; background: white; margin-top: .75rem; }
.image-dialog p { margin: .5rem 0 0; text-align: center; font-size: .875rem; }
.close-dialog { display: block; margin-left: auto; }
.primary-link { min-height: 46px; display: inline-flex; align-items: center; justify-content: center; gap: 1.25rem; padding: .65rem 1.15rem; background: var(--note-button); color: var(--note-on-button) !important; border: 1px solid transparent; border-radius: .45rem; text-decoration: none; font: 600 .9375rem/1.5 var(--sl-font); cursor: pointer; transition: box-shadow .2s, filter .2s; }
.primary-link:hover { filter: brightness(1.08); box-shadow: 0 3px 12px #102c2020; }
.primary-link svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; flex-shrink: 0; }
progress[data-study-progress] { display: block; appearance: none; border: 0; width: 100%; height: 6px; border-radius: 6px; overflow: hidden; background: var(--note-border); color: var(--note-accent); }
progress[data-study-progress]::-webkit-progress-bar { background: var(--note-border); }
progress[data-study-progress]::-webkit-progress-value { background: var(--note-accent); border-radius: 6px; }
progress[data-study-progress]::-moz-progress-bar { background: var(--note-accent); }
button:active { filter: brightness(.96); }
.scheduler { padding: 1.5rem; border: 1px solid var(--note-border); border-radius: var(--note-radius); background: var(--note-surface); margin-block: 1.5rem; }
.lab-controls { display: grid; grid-template-columns: minmax(0, 1fr) 8rem; gap: 1rem; }
.lab-controls label { display: flex; flex-direction: column; gap: .4rem; font-size: .875rem; min-width: 0; }
.scheduler :is(input, select) { font: inherit; font-size: 1rem; color: var(--note-text); background: var(--note-bg); border: 1px solid var(--note-field-border); border-radius: .4rem; padding: .5rem .65rem; min-height: 44px; width: 100%; min-width: 0; }
.scheduler input:disabled { opacity: .55; cursor: not-allowed; }
.scheduler .input-table { display: table; table-layout: fixed; width: 100%; }
.scheduler .input-table th:first-child { width: 20%; }
.scheduler .input-table input { max-width: 9rem; font-variant-numeric: tabular-nums; }
.lab-buttons { display: flex; gap: .75rem; margin-top: 1rem; }
.lab-results { margin-top: 2rem; }
.lab-results h2 { font-size: 1.15rem; margin-bottom: 1rem; }
.lab-results table { font-variant-numeric: tabular-nums; }
.gantt { display: flex; overflow-x: auto; gap: 3px; padding: .5rem 0 1rem; scrollbar-width: thin; }
.gantt-block { flex-basis: 0; min-width: 4rem; white-space: pre; text-align: center; padding: .7rem .25rem; border-radius: .3rem; background: #c6e8df; color: #123f37; font: 600 .8125rem/1.7 var(--sl-font); font-variant-numeric: tabular-nums; }
.process-1 { background: #d8e6fa; color: #153665; }
.process-2 { background: #fae7ba; color: #62440d; }
.process-3 { background: #e8d9f4; color: #4b266a; }
.process--1 { background: #e2e4e5; color: #343e42; }
.lab-metrics { border-left: 3px solid var(--note-accent); padding: .8rem 1rem; background: var(--note-muted-surface); font-weight: 600; font-size: .9375rem; }
@media (max-width: 40rem) {
  .md-typeset.chapter-prose { line-height: 1.9; }
  .md-typeset table { display: block; overflow-x: auto; max-width: 100%; }
  .md-typeset :is(th, td) { padding: .65rem .7rem; }
  .study-toolbar { padding: .65rem .75rem; gap: .5rem; }
  .study-toolbar .reading-size { margin-left: auto; }
  .scheduler { padding: 1rem .75rem; }
  .lab-controls { grid-template-columns: minmax(0, 1fr) 5.5rem; gap: .75rem; }
  .scheduler .input-table :is(th, td) { padding: .6rem .35rem; }
  .scheduler :is(input, select) { padding-inline: .35rem; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; scroll-behavior: auto !important; animation: none !important; } }
@media print { .study-toolbar, .close-dialog, .image-dialog, .lab-controls, .lab-buttons, .zoom-hint { display: none !important; } .figure-zoom { border: 0; } }
/* Starlight wraps headings in a scaled container; use rem to avoid nested em scaling. */
.md-typeset.chapter-prose h2 { font-size: 1.55rem; margin: 0; padding: 0; border: 0; }
.md-typeset.chapter-prose h3 { font-size: 1.2rem; margin: 0; }
/* Each exercise keeps its question, options and answer in one reading group. */
.md-typeset .exercise-item { margin-block: 1.5rem; padding: 1.3rem 1.4rem 0; border: 1px solid var(--note-border); border-radius: .6rem; background: var(--note-surface); }
.md-typeset .exercise-item > p:first-child { margin-top: 0; font-weight: 600; line-height: 1.85; }
.md-typeset .exercise-item > p:first-child strong { font-weight: 600; }
.md-typeset .exercise-options { margin: 1rem 0 1.25rem; }
.md-typeset .exercise-options ul { list-style: none; padding: 0; margin: 0; display: grid; gap: .45rem; }
.md-typeset .exercise-options li { margin: 0; padding: .45rem .75rem; border-radius: .3rem; background: var(--note-muted-surface); line-height: 1.8; font-size: .95em; }
.md-typeset .exercise-options li p { margin: 0; }
.md-typeset .exercise-item details.exercise-answer { border: 0; border-top: 1px solid var(--note-border); border-radius: 0; padding: 0; margin: 1.15rem 0 0; background: transparent; }
.md-typeset .exercise-item .exercise-answer summary { font-size: .875em; font-weight: 500; padding: .8rem 0; min-height: 48px; }
.md-typeset .exercise-item .exercise-answer[open] summary { border-bottom: 0; margin-bottom: .15rem; }
.md-typeset .exercise-item .exercise-answer > :not(summary) { font-size: .95em; }
.md-typeset .exercise-item .exercise-answer > p:first-of-type { margin-top: .5rem; }
.md-typeset .exercise-item .exercise-answer > :last-child { margin-bottom: .5rem; }
@media (max-width: 40rem) { .md-typeset .exercise-item { padding: 1rem 1rem 0; } }

/* Keep navigation and section numbering neutral; reserve blue for actions. */

:root { --md-primary-fg-color: #2859c5; --md-accent-fg-color: #2859c5; }
[data-md-color-scheme="slate"] { --md-default-bg-color: #18191d; --md-default-fg-color: #e8e9ed; --md-default-fg-color--light: #b4b7c2; --md-primary-fg-color: #202126; --md-accent-fg-color: #a9c2ff; --md-typeset-a-color: #a9c2ff; }
.md-header { background: var(--note-surface); color: var(--note-text); border-bottom: 1px solid var(--note-border); box-shadow: none; }
.md-typeset { font-size: 16px; line-height: 1.9; }
.md-grid { max-width: 1480px; }
.md-typeset h1 { color: var(--note-text); font-weight: 700; letter-spacing: -.02em; }
.md-typeset h2 { font-weight: 650; }
.md-typeset img { max-width: 100%; height: auto; }
.md-typeset .chapter-prose { font-size: var(--note-font-size); }
.md-typeset details.exercise-answer > summary { background: transparent; margin: 0; padding-left: 1.3rem; color: var(--note-accent); }
.md-typeset details.exercise-answer > summary::before { display: none; }
.md-typeset .exercise-options ul { list-style: none; padding: 0; }
.md-typeset .exercise-options li { margin-left: 0; }
.md-typeset .exercise-item > p:first-child { margin-top: 0; }
.md-typeset .scheduler table { display: table; width: 100%; }
.md-typeset .scheduler input { color: var(--note-text); }
.md-typeset progress { width: 100%; accent-color: var(--note-accent); }

.md-typeset details.exercise-answer { font-size: inherit; box-shadow: none; }
.md-typeset .exercise-item .exercise-answer > :not(summary) { font-size: .95em; }
.md-typeset .exercise-item .exercise-answer summary { font-size: .875em; }
.md-search__form { background: var(--note-muted-surface); color: var(--note-text); }