:root {
  color-scheme: light;
  --course-bg: #f7f8fa;
  --course-surface: #fff;
  --course-text: #303236;
  --course-heading: #202124;
  --course-muted: #656b73;
  --course-line: #dfe3e7;
  --course-accent: #2e8b57;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--course-bg);
  color: var(--course-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

a { color: inherit; }

.course-detail-header {
  min-height: 58px;
  border-bottom: 1px solid var(--course-line);
  background: var(--course-surface);
}

.course-detail-header a {
  display: flex;
  width: min(1080px, calc(100% - 40px));
  min-height: 58px;
  align-items: center;
  margin: 0 auto;
  color: var(--course-heading);
  font-size: 18px;
  font-weight: 800;
  text-decoration: none;
}

.course-detail-shell {
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
  padding: 30px 0 64px;
}

.course-detail-breadcrumb {
  display: flex;
  gap: 0;
  align-items: center;
  max-width: 100%;
  margin-bottom: 18px;
  overflow-x: auto;
  white-space: nowrap;
  scrollbar-width: none;
}

.course-detail-breadcrumb::-webkit-scrollbar { display: none; }
.course-detail-breadcrumb > * { flex: 0 0 auto; }
.course-detail-breadcrumb span[aria-hidden="true"] { width: 18px; text-align: center; }
.course-detail-breadcrumb a { color: var(--course-accent); font-weight: 700; }

.course-detail-hero {
  display: grid;
  grid-template-columns: minmax(220px, 36%) 1fr;
  gap: 30px;
  align-items: start;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--course-line);
}

.course-detail-cover {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  background: #e8ebef;
}

.course-detail-heading h1 {
  margin: 0 0 8px;
  color: var(--course-heading);
  font-size: clamp(26px, 4vw, 38px);
  line-height: 1.25;
}

.course-detail-english,
.course-detail-meta {
  margin: 0 0 12px;
  color: var(--course-muted);
}

.course-detail-summary,
.course-detail-overview p {
  margin: 0;
  color: var(--course-text);
  font-size: 17px;
  line-height: 1.8;
  text-align: justify;
}

.course-detail-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }
.course-detail-button { padding: 9px 15px; border: 1px solid var(--course-accent); color: var(--course-accent); text-decoration: none; }
.course-detail-button:hover, .course-detail-button:focus-visible { background: var(--course-accent); color: #fff; }
.course-detail-button-secondary { border-color: var(--course-line); color: var(--course-muted); }

.course-detail-overview,
.course-detail-content { max-width: 860px; margin: 30px auto 0; }
.course-detail-overview h2,
.course-detail-content h2 { margin: 0 0 12px; color: var(--course-heading); font-size: 22px; }
.course-detail-overview h2:not(:first-child) { margin-top: 24px; }
.course-detail-overview ul { padding-left: 1.4em; line-height: 1.8; }
.course-detail-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.course-detail-tags span { padding: 4px 9px; border: 1px solid var(--course-line); color: var(--course-muted); font-size: 14px; }
.course-detail-content { padding-top: 26px; border-top: 1px solid var(--course-line); }
.course-detail-status { color: var(--course-muted); line-height: 1.7; }
.course-detail-content-body { font-size: 17px; line-height: 1.9; }
.course-detail-content-body p { margin: 0 0 1em; }
.course-detail-content-body h3 { margin: 1.6em 0 .7em; color: var(--course-heading); }
.course-detail-content-body ul { padding-left: 1.5em; }
.course-detail-content-body li { margin-bottom: .5em; }
.course-detail-error { color: #a33a3a; }

.course-detail-content-original-education {
  width: 100%;
  max-width: 860px;
  margin: 30px auto 0;
  padding-top: 0;
  border-top: 0;
}

.course-detail-original-education-intro {
  width: 100%;
  max-width: 860px;
  margin: 30px auto 0;
  text-align: center;
}

.course-detail-original-education-intro img {
  display: block;
  width: 100%;
  height: auto;
  margin: 0 0 20px;
  object-fit: cover;
}

.course-detail-original-education-intro h1 {
  margin: 0 0 4px;
  color: var(--course-heading);
  font-size: 20px;
  font-weight: 800;
  line-height: 1.35;
}

.course-detail-content-original-education .course-detail-content-body {
  color: #303236;
  font-size: 18px;
  line-height: 2;
  text-align: justify;
  text-align-last: left;
}

.course-detail-content-original-education .course-detail-content-body > p {
  margin: 0 0 1em;
  text-align: justify;
  text-align-last: left;
}

.course-detail-content-original-education .equip-article-collapsible {
  margin: 0 0 14px;
  overflow: hidden;
  border: 1px solid #d9dee5;
  border-radius: 8px;
  background: #f8fafc;
  text-align: left;
}

.course-detail-content-original-education .equip-article-collapsible > summary {
  padding: 12px 16px;
  color: #2f5f8f;
  font-weight: 800;
  line-height: 1.6;
  cursor: pointer;
  list-style-position: inside;
}

.course-detail-content-original-education .equip-article-collapsible-body {
  padding: 0 18px 4px;
}

.course-detail-content-original-education .equip-article-collapsible-body li { margin-bottom: 0; }

body.io-black-mode .course-detail-content-original-education .equip-article-collapsible {
  border-color: #414a53;
  background: #202428;
}

body.io-black-mode .course-detail-content-original-education .equip-article-collapsible > summary { color: #9fc5f2; }
body.io-black-mode .course-detail-content-original-education .course-detail-content-body { color: #c4cad1; }

/* Match the education homepage course introduction without loading the homepage shell. */
.equip-book-detail {
  width: 100%;
  max-width: 1080px;
  margin: 18px auto 0;
  text-align: left;
}

/* Keep the 144 Grammar, Logic and Rhetoric detail pages on one shared edge. */
.degree-stage-course-detail {
  width: min(1080px, calc(100% - 40px));
}

.degree-stage-course-detail > .equip-book-detail,
.degree-course-detail-aligned > .equip-book-detail {
  width: 100%;
  max-width: none;
  margin-left: 0;
  margin-right: 0;
}

.degree-stage-course-detail > .course-detail-breadcrumb,
.degree-course-detail-aligned > .course-detail-breadcrumb {
  width: 100%;
  max-width: none;
  margin-left: 0;
  margin-right: 0;
}

.degree-course-detail-aligned {
  width: min(1080px, calc(100% - 40px));
}

.equip-book-intro {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 500px));
  gap: 80px;
  align-items: start;
  justify-content: start;
}

.equip-book-info { width: 100%; max-width: 500px; }

.equip-book-cover {
  display: block;
  width: 100%;
  max-width: 500px;
  height: auto;
  aspect-ratio: 1;
  border-radius: 6px;
  object-fit: cover;
  box-shadow: 0 8px 24px rgba(32, 33, 36, .12);
}

.equip-book-info-title {
  margin: 0 0 10px;
  color: var(--course-heading);
  font-size: 28px;
  font-weight: 800;
  line-height: 1.35;
}

.equip-course-english-title {
  margin: 0 0 10px;
  color: var(--course-muted);
  font-size: 17px;
  line-height: 1.7;
}

.equip-course-scroll-body { min-width: 0; }
.equip-book-summary-line,
.equip-course-objectives,
.equip-course-meta,
.equip-book-category-line,
.equip-book-tags-line {
  color: var(--course-text);
  font-size: 17px;
  line-height: 1.85;
}

.equip-book-summary-line { margin: 0; text-align: justify; }
.equip-course-objectives { margin: 0 0 18px; }
.equip-course-objectives-title { margin: 0 0 6px; color: var(--course-heading); font-size: 18px; font-weight: 800; line-height: 1.6; }
.equip-course-objective-list { margin: 0; padding-left: 1.25em; }
.equip-book-field-label { font-weight: 800; }
.equip-book-category-line,
.equip-book-tags-line { display: flex; align-items: baseline; }
.equip-book-category-line { margin-top: 10px; }
.equip-book-tags-line { margin-top: 5px; }
.equip-book-category-list,
.equip-book-tags-list { display: flex; flex-wrap: wrap; gap: 7px; margin: 0; padding: 0 0 0 2px; list-style: none; }
.equip-book-category-item,
.equip-book-tag-item { padding: 2px 9px; border-radius: 4px; font-size: 17px; line-height: 1.85; }
.equip-book-category-item { background: #e7f4ec; color: #3f7352; }
.equip-book-tag-item:nth-child(5n + 1) { background: #e7f1fb; color: #35658f; }
.equip-book-tag-item:nth-child(5n + 2) { background: #f0eafb; color: #70538f; }
.equip-book-tag-item:nth-child(5n + 3) { background: #fff0df; color: #96601f; }
.equip-book-tag-item:nth-child(5n + 4) { background: #fbe9f0; color: #94536c; }
.equip-book-tag-item:nth-child(5n) { background: #eef0f2; color: #5d646c; }
.equip-course-meta { margin: 10px 0 0; }
.equip-book-resource-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 10px; }
.equip-book-resource-button { display: inline-flex; min-width: 126px; min-height: 42px; align-items: center; justify-content: center; gap: 8px; padding: 8px 18px; border: 0; border-radius: 6px; color: #fff; font-family: inherit; font-size: 16px; font-weight: 700; line-height: 1.4; text-decoration: none; cursor: pointer; }
.equip-book-resource-button:hover, .equip-book-resource-button:focus-visible { color: #fff; text-decoration: none; }
.equip-book-resource-button.is-official { background: #c62828; }
.equip-book-resource-button.is-official:hover, .equip-book-resource-button.is-official:focus-visible { background: #a81f1f; }
.education-course-introduction-primary-action-red .equip-book-resource-button.is-official[aria-disabled="true"] { background: #c62828; opacity: 1; }
.equip-book-resource-button.is-detail { background: #2f7d4b; }
.equip-book-share-row { display: flex; align-items: center; justify-content: center; margin-top: 38px; padding-top: 20px; border-top: 1px solid var(--course-line); }
.equip-book-share { display: inline-flex; align-items: center; gap: 6px; padding: 0; border: 0; background: transparent; color: var(--course-muted); cursor: pointer; font: 500 16px/1.5 inherit; }

@media (min-width: 1101px) {
  .education-home-course-detail .equip-book-info { display: flex; flex-direction: column; height: 500px; min-height: 0; }
  .education-home-course-detail .equip-course-scroll-body { flex: 1 1 auto; min-height: 0; overflow-y: auto; padding-right: 8px; }
}

@media (max-width: 1100px) {
  .equip-book-intro { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; }
}

@media (max-width: 767px) {
  .equip-book-intro { grid-template-columns: 1fr; gap: 20px; }
  .equip-book-cover, .equip-book-info { max-width: none; }
  .equip-book-info-title { font-size: 25px; }
  .equip-course-english-title, .equip-book-summary-line, .equip-course-objectives, .equip-course-meta, .equip-book-category-line, .equip-book-tags-line { font-size: 16px; }
  .equip-book-resource-button { flex: 1 1 0; }
  .course-detail-content-original-education .course-detail-content-body { font-size: 17px; line-height: 1.9; }
}

body.io-black-mode .equip-book-info-title,
body.io-black-mode .equip-course-objectives-title { color: var(--course-heading); }
body.io-black-mode .equip-course-english-title,
body.io-black-mode .equip-course-objectives,
body.io-black-mode .equip-course-meta,
body.io-black-mode .equip-book-summary-line,
body.io-black-mode .equip-book-category-line,
body.io-black-mode .equip-book-tags-line,
body.io-black-mode .equip-book-share { color: var(--course-muted); }
body.io-black-mode .equip-book-cover { box-shadow: 0 8px 24px rgba(0, 0, 0, .34); }

body.io-black-mode { --course-bg: #111416; --course-surface: #1b2024; --course-text: #e7eaee; --course-heading: #fff; --course-muted: #b2bbc5; --course-line: #414a53; --course-accent: #83d5a4; }

@media (max-width: 767px) {
  .course-detail-header a, .course-detail-shell { width: calc(100% - 28px); }
  .course-detail-shell { padding-top: 22px; }
  .course-detail-hero { grid-template-columns: 1fr; gap: 20px; }
  .course-detail-cover { max-height: 300px; }
  .course-detail-summary, .course-detail-overview p { font-size: 16px; }
}

@media (prefers-color-scheme: dark) {
  body:not(.io-grey-mode) { --course-bg: #111416; --course-surface: #1b2024; --course-text: #e7eaee; --course-heading: #fff; --course-muted: #b2bbc5; --course-line: #414a53; --course-accent: #83d5a4; }
}