/*
 * Shared SEBook visual system.
 *
 * This file centralizes the UCLA/SEBook visual language so layouts and
 * includes do not duplicate the same navbar, sidebar, surface, and widget
 * styling inline. The site theme uses html.dark-mode, not media queries.
 */

:root {
  --sebook-navy: #17324d;
  --sebook-navy-dark: #061d31;
  --sebook-on-gold: #061d31;
  --sebook-blue: #2774AE;
  --sebook-blue-dark: #1e5c8a;
  --sebook-blue-soft: #B9D9EB;
  --sebook-blue-faint: #eef7ff;
  --sebook-gold: #FFD100;
  --sebook-gold-dark: #B38B00;
  --sebook-button-bg: #ffffff;
  --sebook-button-bg-hover: #eef7ff;
  --sebook-button-text: #003B5C;
  --sebook-button-border: #2774AE;
  --sebook-button-primary-bg: #2774AE;
  --sebook-button-primary-text: #ffffff;
  --sebook-surface: #ffffff;
  --sebook-surface-soft: #f7fbff;
  --sebook-surface-band: #eef6fc;
  --sebook-border: #c8d6e2;
  --sebook-shadow: 0 16px 34px rgba(0, 59, 92, 0.14);
}

html.dark-mode {
  --sebook-navy: #B9D9EB;
  --sebook-navy-dark: #e6f4ff;
  --sebook-on-gold: #061d31;
  --sebook-blue: #8BB8E8;
  --sebook-blue-dark: #B9D9EB;
  --sebook-blue-soft: #2b4b68;
  --sebook-blue-faint: #132235;
  --sebook-button-bg: #101b28;
  --sebook-button-bg-hover: #17324d;
  --sebook-button-text: #e6f4ff;
  --sebook-button-border: #8BB8E8;
  --sebook-button-primary-bg: #2774AE;
  --sebook-button-primary-text: #ffffff;
  --sebook-surface: #111827;
  --sebook-surface-soft: #0f1722;
  --sebook-surface-band: #101b28;
  --sebook-border: #31455d;
  --sebook-shadow: 0 18px 38px rgba(0, 0, 0, 0.42);
}

body.default-layout,
body.blog-layout,
body.sebook-layout,
body.framework-layout,
body.sebook-combined-layout,
body.tutorial-layout {
  font-size: var(--font-size-body, 17px);
  line-height: var(--line-height-body, 1.6);
  background:
    radial-gradient(circle at top right, rgba(185, 217, 235, 0.32), transparent 34%),
    linear-gradient(180deg, var(--sebook-surface-soft), var(--color-bg, #fdfdfd));
  color: var(--color-text, #111);
}

html.dark-mode body.default-layout,
html.dark-mode body.blog-layout,
html.dark-mode body.sebook-layout,
html.dark-mode body.framework-layout,
html.dark-mode body.sebook-combined-layout,
html.dark-mode body.tutorial-layout {
  background:
    radial-gradient(circle at top right, rgba(185, 217, 235, 0.13), transparent 34%),
    linear-gradient(180deg, #0f1722, #111827);
  color: var(--color-text, #e6edf3);
}

/* Shared navbar */
#navnav.navbar {
  background: #17324d !important;
  border: 0 !important;
  border-bottom: 5px solid var(--sebook-gold) !important;
  box-shadow: 0 10px 26px rgba(0, 59, 92, 0.18);
}

#navnav .navbar-brand,
#navnav .navbar-brand:visited {
  color: #ffffff !important;
  font-weight: 700 !important;
  letter-spacing: 0 !important;
  text-decoration: none !important;
}

#navnav .navbar-brand:hover,
#navnav .navbar-brand:focus {
  color: var(--sebook-gold) !important;
  text-decoration: none !important;
}

#navnav .navbar-nav > li > a,
#navnav .navbar-nav > li > a:visited,
#navnav .navbar-right > a,
#navnav .navbar-right > a:visited,
#navnav .navbar-right > label,
#navnav #tts-read-btn,
#navnav .tutorial-help-menu-toggle {
  border-radius: var(--radius-pill, 999px) !important;
  color: #eef7ff !important;
  font-weight: 600 !important;
  letter-spacing: 0 !important;
  text-decoration: none !important;
}

#navnav .navbar-nav > li > a {
  margin: 3px 3px;
}

#navnav .navbar-nav > li > a:hover,
#navnav .navbar-nav > li > a:focus,
#navnav .navbar-right > a:hover,
#navnav .navbar-right > a:focus,
#navnav .navbar-right > label:hover,
#navnav .navbar-right > label:focus,
#navnav .tutorial-nav-link:hover,
#navnav .tutorial-nav-link:focus,
#navnav .tutorial-nav-control:hover,
#navnav .tutorial-nav-control:focus,
#navnav .tutorial-nav-button:hover,
#navnav .tutorial-nav-button:focus-visible,
#navnav #tts-read-btn:hover,
#navnav #tts-read-btn:focus-visible,
#navnav .tutorial-help-menu-toggle:hover,
#navnav .tutorial-help-menu-toggle:focus-visible {
  background: var(--sebook-gold) !important;
  color: var(--sebook-on-gold) !important;
  text-decoration: none !important;
}

#navnav .tutorial-nav-link:hover *,
#navnav .tutorial-nav-link:focus *,
#navnav .tutorial-nav-control:hover *,
#navnav .tutorial-nav-control:focus *,
#navnav .tutorial-nav-button:hover *,
#navnav .tutorial-nav-button:focus-visible * {
  color: inherit !important;
}

#navnav .navbar-nav > li.active > a,
#navnav .navbar-nav > li.active > a:visited,
#navnav .navbar-nav > li.active > a:hover,
#navnav .navbar-nav > li.active > a:focus,
#navnav .navbar-nav > li > a.active,
#navnav .navbar-nav > li > a.active:visited,
#navnav .navbar-nav > li > a[aria-current="true"],
#navnav .navbar-nav > li > a[aria-current="true"]:visited {
  background: var(--sebook-gold) !important;
  color: var(--sebook-on-gold) !important;
  box-shadow: inset 0 -4px 0 #ffffff, 0 0 0 2px rgba(255, 255, 255, 0.18);
  text-decoration: none !important;
}

#navnav .navbar-toggle {
  border-color: rgba(255, 255, 255, 0.72) !important;
}

#navnav .navbar-toggle:focus-visible {
  outline: var(--focus-width, 3px) solid var(--focus-color, #FFD100);
  outline-offset: var(--focus-offset, 2px);
}

html.dark-mode #navnav.navbar {
  background: #0b1f33 !important;
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.42);
}

/* Shared page headers and content chrome */
.intro-header {
  background:
    radial-gradient(circle at 100% 0%, rgba(255, 209, 0, 0.16) 0 110px, transparent 112px),
    radial-gradient(circle at 0% 100%, rgba(139, 184, 232, 0.22) 0 150px, transparent 152px),
    linear-gradient(180deg, #ffffff, #f7fbff);
  border-bottom: 1px solid var(--sebook-border);
  box-shadow: 0 12px 32px rgba(0, 59, 92, 0.09);
}

.intro-header h1,
.post-title,
.page-heading,
.blog-post-header h1,
body.default-layout h1,
body.default-layout h2,
body.framework-layout h1,
body.framework-layout h2,
body.sebook-combined-layout h1,
body.sebook-combined-layout h2 {
  color: #17324d;
  font-weight: 800;
  letter-spacing: 0;
  overflow-wrap: anywhere;
  -webkit-text-stroke: 0;
}

.intro-header hr.small,
.blog-post-header h1::after,
body.sebook-layout #main-content section > h1::after,
body.sebook-layout #main-content section > h2::after,
body.blog-layout .blog-post-content h2::after,
body.default-layout h2::after,
body.framework-layout h2::after,
body.sebook-combined-layout section > h1::after,
body.sebook-combined-layout section > h2::after {
  content: '';
  display: block;
  width: 82px;
  height: 5px;
  margin: 8px auto 0;
  border: 0;
  border-radius: var(--radius-pill, 999px);
  background: linear-gradient(90deg, var(--sebook-blue) 0 72%, var(--sebook-gold) 72% 100%);
}

body.sebook-layout #main-content section > h1::after,
body.sebook-layout #main-content section > h2::after,
body.blog-layout .blog-post-content h2::after,
body.default-layout h2::after,
body.framework-layout h2::after,
body.sebook-combined-layout section > h1::after,
body.sebook-combined-layout section > h2::after {
  margin-left: 0;
  margin-right: 0;
}

body.sebook-layout .intro-header {
  margin: -70px -20px 20px;
}

#sebook-content-wrapper,
#blog-content-wrapper {
  display: flex;
  min-height: calc(100vh - 60px);
  background:
    radial-gradient(circle at top right, rgba(139, 184, 232, 0.22), transparent 34%),
    linear-gradient(180deg, #f7fbff, #ffffff);
}

#blog-content-wrapper {
  min-height: calc(100vh - 200px);
}

body.sebook-layout #main-content,
body.blog-layout #main-content {
  flex: 1;
  padding: 20px;
  min-width: 0;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(251, 253, 255, 0.98));
  color: var(--color-text, #24292f);
}

body.blog-layout #main-content {
  padding: 0;
}

body.sebook-layout #main-content .container,
body.sebook-layout #main-content .intro-header .container {
  width: 100%;
  max-width: 100%;
}

body.sebook-layout #main-content .row {
  margin-right: 0;
  margin-left: 0;
}

body.sebook-layout #main-content pre,
body.sebook-layout #main-content code,
body.sebook-layout #main-content .highlight pre,
body.sebook-layout #main-content .inline-language-switcher {
  max-width: 100%;
}

body.sebook-layout #main-content .bibliography,
body.sebook-layout #main-content .bib-link {
  max-width: 100%;
  overflow-wrap: anywhere;
}

body.sebook-layout #main-content pre,
body.sebook-layout #main-content .highlight pre {
  overflow-x: auto;
}

body.sebook-layout #main-content h1,
body.sebook-layout #main-content h2,
body.blog-layout #main-content h1,
body.blog-layout #main-content h2,
body.framework-layout #main-content h1,
body.framework-layout #main-content h2,
body.sebook-combined-layout #main-content h1,
body.sebook-combined-layout #main-content h2 {
  color: #17324d;
  font-weight: 800;
  letter-spacing: 0;
  text-shadow: none;
  -webkit-text-stroke: 0;
}

html.dark-mode .intro-header,
html.dark-mode #sebook-content-wrapper,
html.dark-mode #blog-content-wrapper {
  background:
    radial-gradient(circle at top right, rgba(139, 184, 232, 0.16), transparent 34%),
    linear-gradient(180deg, #0f1722, #111827);
  border-color: var(--sebook-border);
}

html.dark-mode body.sebook-layout #main-content,
html.dark-mode body.blog-layout #main-content {
  background: linear-gradient(180deg, rgba(17, 24, 39, 0.97), rgba(15, 23, 34, 0.98));
  color: #e5e7eb;
}

html.dark-mode .intro-header h1,
html.dark-mode .post-title,
html.dark-mode .page-heading,
html.dark-mode .blog-post-header h1,
html.dark-mode body.sebook-layout #main-content h1,
html.dark-mode body.sebook-layout #main-content h2,
html.dark-mode body.blog-layout #main-content h1,
html.dark-mode body.blog-layout #main-content h2,
html.dark-mode body.framework-layout #main-content h1,
html.dark-mode body.framework-layout #main-content h2,
html.dark-mode body.sebook-combined-layout #main-content h1,
html.dark-mode body.sebook-combined-layout #main-content h2 {
  color: var(--sebook-gold) !important;
}

html.dark-mode .intro-header hr.small,
html.dark-mode .blog-post-header h1::after,
html.dark-mode body.sebook-layout #main-content section > h1::after,
html.dark-mode body.sebook-layout #main-content section > h2::after,
html.dark-mode body.blog-layout .blog-post-content h2::after,
html.dark-mode body.default-layout h2::after,
html.dark-mode body.framework-layout h2::after,
html.dark-mode body.sebook-combined-layout section > h1::after,
html.dark-mode body.sebook-combined-layout section > h2::after {
  background: linear-gradient(90deg, #8BB8E8 0 72%, var(--sebook-gold) 72% 100%);
}

body.framework-layout #main-content,
body.sebook-combined-layout #main-content {
  min-width: 0;
}

body.framework-layout article.post-content,
body.sebook-combined-layout #main-content {
  color: var(--color-text, #24292f);
}

.info-page-nav.navbar-fixed-top {
  position: sticky;
  top: 0;
  right: auto;
  left: auto;
}

html.dark-mode body.framework-layout article.post-content,
html.dark-mode body.sebook-combined-layout #main-content {
  color: #e5e7eb;
}

/* SEBook sidebar */
body.sebook-layout #sidebar {
  width: 260px;
  max-width: 80vw;
  min-width: 220px;
  flex-shrink: 0;
  overflow-y: auto;
  margin: 0;
  padding: 0;
  background: #f4f9fd;
  border-right: 1px solid var(--sebook-border);
  box-shadow: 10px 0 28px rgba(0, 59, 92, 0.1);
}

#sidebar-toggle {
  display: none;
  position: fixed;
  top: 60px;
  left: -5px;
  z-index: 1000;
  padding: 10px;
  border: 2px solid #ffffff !important;
  border-left: 0 !important;
  border-radius: var(--radius-md, 8px);
  background: var(--sebook-blue) !important;
  color: #ffffff !important;
  box-shadow: 0 10px 22px rgba(0, 59, 92, 0.18);
  cursor: pointer;
  font-weight: 700;
}

#sidebar-toggle:focus-visible {
  outline: var(--focus-width, 3px) solid var(--focus-color, #FFD100);
  outline-offset: var(--focus-offset, 2px);
}

.sebook-sidebar-nav {
  min-height: 100%;
  background:
    radial-gradient(circle at top left, rgba(185, 217, 235, 0.34), transparent 38%),
    linear-gradient(180deg, #f7fbff, #e8f3fb);
  color: #17324d;
  padding: 0;
  margin: 0;
  font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
}

.sebook-nav-list,
.sebook-nav-sublist,
.sebook-nav-itemlist {
  list-style: none;
  margin: 0;
  padding: 0;
}

.sebook-nav-item,
.sebook-nav-subitem {
  margin: 0;
  border-bottom: 1px solid #c8ddec;
}

.sebook-nav-row,
.sebook-nav-subrow {
  display: flex;
  align-items: stretch;
  width: 100%;
  position: relative;
  isolation: isolate;
}

.sebook-nav-link,
.sebook-nav-link:visited,
.sebook-nav-sublink,
.sebook-nav-sublink:visited,
.sebook-nav-itemlink,
.sebook-nav-itemlink:visited {
  box-sizing: border-box;
  min-width: 0;
  border-left: 5px solid transparent;
  color: #17324d;
  cursor: pointer;
  border-radius: 0 !important;
  font-weight: 700;
  text-decoration: none !important;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s;
}

.sebook-nav-link,
.sebook-nav-link:visited {
  display: flex;
  align-items: center;
  flex: 1 1 auto;
  padding: 13px 14px;
  font-size: 1em;
}

.sebook-nav-sublink,
.sebook-nav-sublink:visited {
  display: flex;
  align-items: center;
  flex: 1 1 auto;
  padding: 10px 18px 10px 48px;
  color: #174466;
  font-size: 0.95em;
  font-weight: 650;
}

.sebook-nav-itemlink,
.sebook-nav-itemlink:visited {
  display: block;
  width: 100%;
  padding: 9px 18px 9px 62px;
  font-size: 0.92em;
  font-weight: 650;
}

.sebook-nav-text {
  flex: 1;
}

.sebook-nav-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  margin-right: 10px;
  border-radius: var(--radius-circle, 50%);
  background: var(--sebook-blue);
  color: #ffffff;
  font-size: 1em;
  box-shadow: inset 0 -3px 0 rgba(0, 59, 92, 0.22), 0 5px 12px rgba(0, 59, 92, 0.14);
  flex: 0 0 auto;
}

.sebook-nav-toggle {
  flex: 0 0 auto;
  min-width: 40px;
  min-height: 40px;
  margin: 0;
  padding: 8px 10px;
  border: 0;
  border-left: 1px solid #c8ddec;
  background: transparent;
  color: #17324d;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font: inherit;
  line-height: 1;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s;
}

.sebook-nav-toggle > span {
  display: inline-block;
  line-height: 1;
  transition: transform 0.2s;
}

.sebook-nav-link:hover,
.sebook-nav-toggle:hover {
  background-color: #dceefa;
  color: #003B5C !important;
  text-decoration: none !important;
}

.sebook-nav-sublink:hover,
.sebook-nav-subrow .sebook-nav-toggle:hover {
  background-color: #d3e9f7;
  color: #003B5C !important;
  text-decoration: none !important;
}

.sebook-nav-itemlink:hover {
  background-color: #cbe4f5;
  color: #003B5C;
  text-decoration: none !important;
}

.sebook-nav-toggle:focus-visible,
.sebook-nav-link:focus-visible,
.sebook-nav-sublink:focus-visible,
.sebook-nav-itemlink:focus-visible {
  background-color: #dceefa;
  color: #003B5C !important;
  outline: var(--focus-width, 3px) solid var(--focus-color, #005587);
  outline-offset: -3px;
}

.sebook-nav-toggle:focus-visible {
  border-radius: var(--radius-sm, 4px);
  outline-offset: var(--focus-offset, 2px);
}

.sebook-nav-item.has-subtopics .sebook-nav-toggle.open,
.sebook-nav-item.has-subtopics .sebook-nav-toggle[aria-expanded="true"],
.sebook-nav-subitem.has-subitems .sebook-nav-toggle.open,
.sebook-nav-subitem.has-subitems .sebook-nav-toggle[aria-expanded="true"] {
  transform: none !important;
}

.sebook-nav-item.has-subtopics .sebook-nav-toggle.open > span,
.sebook-nav-item.has-subtopics .sebook-nav-toggle[aria-expanded="true"] > span,
.sebook-nav-subitem.has-subitems .sebook-nav-toggle.open > span,
.sebook-nav-subitem.has-subitems .sebook-nav-toggle[aria-expanded="true"] > span {
  transform: rotate(90deg);
}

.sebook-nav-sublist {
  display: none;
  background-color: #e9f4fb;
  box-shadow: inset 5px 0 0 rgba(255, 209, 0, 0.68);
}

.sebook-nav-itemlist {
  display: none;
  background-color: #dfeefa;
}

.sebook-nav-item.has-subtopics.open > .sebook-nav-sublist,
.sebook-nav-subitem.has-subitems.open > .sebook-nav-itemlist {
  display: block;
}

.sebook-nav-link.current,
.sebook-nav-sublink.current,
.sebook-nav-itemlink.current {
  background-color: var(--sebook-blue);
  color: #ffffff !important;
  border-left-color: var(--sebook-gold);
  font-weight: 750;
  text-decoration: none !important;
}

.sebook-nav-link.current + .sebook-nav-toggle,
.sebook-nav-sublink.current + .sebook-nav-toggle {
  background-color: var(--sebook-blue);
  border-left-color: rgba(255, 255, 255, 0.34);
  color: #ffffff !important;
}

.sebook-nav-link.current:visited,
.sebook-nav-sublink.current:visited,
.sebook-nav-itemlink.current:visited {
  color: #ffffff !important;
}

.sebook-nav-link.current .sebook-nav-icon {
  background: var(--sebook-gold);
  color: #17324d;
  box-shadow: inset 0 -3px 0 rgba(0, 59, 92, 0.18), 0 5px 12px rgba(0, 59, 92, 0.2);
}

.sebook-nav-link.current:hover,
.sebook-nav-link.current:hover + .sebook-nav-toggle,
.sebook-nav-link.current + .sebook-nav-toggle:hover,
.sebook-nav-sublink.current:hover,
.sebook-nav-sublink.current:hover + .sebook-nav-toggle,
.sebook-nav-sublink.current + .sebook-nav-toggle:hover,
.sebook-nav-itemlink.current:hover {
  background-color: var(--sebook-blue-dark);
  color: #ffffff !important;
}

html.dark-mode body.sebook-layout #sidebar {
  background: #101b28;
  border-right-color: var(--sebook-border);
  box-shadow: 10px 0 28px rgba(0, 0, 0, 0.36);
}

html.dark-mode #sidebar-toggle {
  background: #2774AE !important;
  border-color: #8BB8E8 !important;
  color: #ffffff !important;
}

html.dark-mode .sebook-sidebar-nav {
  background:
    radial-gradient(circle at top left, rgba(185, 217, 235, 0.12), transparent 38%),
    linear-gradient(180deg, #101b28, #0d1825);
  color: #e6f4ff;
}

html.dark-mode .sebook-nav-item,
html.dark-mode .sebook-nav-subitem {
  border-bottom-color: #31455d;
}

html.dark-mode .sebook-nav-link,
html.dark-mode .sebook-nav-link:visited,
html.dark-mode .sebook-nav-sublink,
html.dark-mode .sebook-nav-sublink:visited,
html.dark-mode .sebook-nav-itemlink,
html.dark-mode .sebook-nav-itemlink:visited,
html.dark-mode .sebook-nav-toggle {
  color: #d7ecff !important;
  text-decoration: none !important;
}

html.dark-mode .sebook-nav-icon {
  background: #2774AE;
  color: #ffffff;
  box-shadow: inset 0 -3px 0 rgba(0, 0, 0, 0.28), 0 5px 12px rgba(0, 0, 0, 0.34);
}

html.dark-mode .sebook-nav-toggle {
  border-left-color: #31455d;
}

html.dark-mode .sebook-nav-link:hover,
html.dark-mode .sebook-nav-toggle:hover,
html.dark-mode .sebook-nav-link:focus-visible,
html.dark-mode .sebook-nav-sublink:focus-visible,
html.dark-mode .sebook-nav-itemlink:focus-visible {
  background-color: #1b3d5c !important;
  color: #ffffff !important;
}

html.dark-mode .sebook-nav-sublist {
  background-color: #112338 !important;
  box-shadow: inset 5px 0 0 rgba(255, 209, 0, 0.72);
}

html.dark-mode .sebook-nav-subrow {
  background-color: #122841 !important;
}

html.dark-mode .sebook-nav-subitem:nth-child(even) .sebook-nav-subrow {
  background-color: #10243a !important;
}

html.dark-mode .sebook-nav-sublink:hover,
html.dark-mode .sebook-nav-subrow .sebook-nav-toggle:hover,
html.dark-mode .sebook-nav-itemlink:hover {
  background-color: #204968 !important;
  color: #ffffff !important;
}

html.dark-mode .sebook-nav-itemlist {
  background-color: #0f2033 !important;
}

html.dark-mode .sebook-nav-link.current,
html.dark-mode .sebook-nav-sublink.current,
html.dark-mode .sebook-nav-itemlink.current {
  background-color: #2774AE !important;
  color: #ffffff !important;
  border-left-color: var(--sebook-gold);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08), inset 0 -1px 0 rgba(0, 0, 0, 0.18);
}

html.dark-mode .sebook-nav-link.current + .sebook-nav-toggle,
html.dark-mode .sebook-nav-sublink.current + .sebook-nav-toggle {
  background-color: #2774AE !important;
  border-left-color: rgba(255, 255, 255, 0.28);
  color: #ffffff !important;
}

html.dark-mode .sebook-nav-link.current:hover,
html.dark-mode .sebook-nav-link.current:hover + .sebook-nav-toggle,
html.dark-mode .sebook-nav-link.current + .sebook-nav-toggle:hover,
html.dark-mode .sebook-nav-sublink.current:hover,
html.dark-mode .sebook-nav-sublink.current:hover + .sebook-nav-toggle,
html.dark-mode .sebook-nav-sublink.current + .sebook-nav-toggle:hover,
html.dark-mode .sebook-nav-itemlink.current:hover {
  background-color: #1F6EBD !important;
  color: #ffffff !important;
}

html.dark-mode-transition #sidebar,
html.dark-mode-transition #sidebar * {
  transition: background-color 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease !important;
}

/* Shared SEBook widgets */
.inline-language-switcher,
.highlight-toggle-container,
.blog-post-item,
.panel-default,
.jumbotron,
.action-box {
  border: 1px solid var(--sebook-border);
  border-radius: var(--radius-md, 8px);
  background: var(--sebook-surface);
  box-shadow: var(--shadow-sm);
}

.inline-language-switcher {
  margin: 18px 0 24px;
  overflow: hidden;
}

.inline-language-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-xs, 6px);
  padding: var(--sp-sm, 8px);
  border-bottom: 1px solid var(--sebook-border);
  background: var(--sebook-surface-band);
}

.inline-language-tabs button {
  border: 1px solid transparent;
  border-radius: var(--radius-sm, 4px);
  background: transparent;
  color: var(--color-text, #24292f);
  font-weight: 650;
  line-height: 1.2;
  padding: 7px 11px;
}

.inline-language-tabs button:hover,
.inline-language-tabs button:focus {
  border-color: var(--sebook-blue-dark);
  background: #dbeeff;
  color: #061d31;
  outline: var(--focus-width, 3px) solid var(--focus-color, #2774AE);
  outline-offset: var(--focus-offset, 2px);
  box-shadow: 0 0 0 2px var(--sebook-surface);
}

.inline-language-tabs button:focus:not(:focus-visible) {
  outline: none;
  box-shadow: none;
}

.inline-language-tabs button[aria-selected="true"] {
  border-color: var(--sebook-blue-dark);
  background: var(--sebook-blue);
  color: #ffffff;
}

.inline-language-tabs button[aria-selected="true"]:hover,
.inline-language-tabs button[aria-selected="true"]:focus {
  border-color: var(--sebook-gold-dark);
  background: var(--sebook-gold);
  color: var(--sebook-on-gold);
}

.inline-language-panel {
  display: none;
  padding: 0 12px 12px;
}

.inline-language-panel.is-active {
  display: block;
}

.inline-language-panel pre {
  margin-top: 12px;
  scroll-margin-top: 96px;
}

/* WCAG 2.2 SC 2.4.11 (Focus Not Obscured) — the sebook layout has a sticky
   navbar (~96px tall). When Tab moves focus to a link or button in main
   content, the browser's automatic scrollIntoView can land it under the
   navbar. Reserve the navbar's height so the focused element stays visible. */
#main-content a,
#main-content button {
  scroll-margin-top: 96px;
}

.inline-language-panel pre:focus,
#main-content pre[tabindex]:focus {
  outline: var(--focus-width, 3px) solid var(--focus-color, #2774AE);
  outline-offset: 3px;
  box-shadow: 0 0 0 2px var(--sebook-surface);
}

.highlight-toggle-container {
  gap: var(--sp-md, 12px);
  flex-wrap: wrap;
  align-items: center;
  padding: var(--sp-sm, 8px) var(--sp-md, 12px);
  margin: 12px 0 18px;
}

.toggle-control-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.toggle-control-row.is-spaced {
  margin-right: 20px;
}

.tts-read-inline-icon {
  margin-right: 5px;
}

#tts-read-btn {
  font-size: 0.95em !important;
}

body.sebook-layout #tts-read-btn {
  background: none;
  border: 1px solid var(--sebook-blue);
  color: var(--sebook-blue);
  border-radius: var(--radius-md, 8px);
  padding: 4px 12px;
  cursor: pointer;
  font-weight: 700;
  white-space: nowrap;
}

.tutorial-navbar-header,
.tutorial-back-link,
.tutorial-navbar-title,
.tutorial-navbar-actions,
.tutorial-nav-control,
.tutorial-nav-link,
.tutorial-nav-button {
  align-items: center;
}

.tutorial-navbar-header {
  display: flex;
  min-height: 45px;
}

.tutorial-back-link,
.tutorial-navbar-title {
  display: flex !important;
  height: 100%;
  padding-top: 0 !important;
  padding-bottom: 0 !important;
  font-size: var(--tutorial-navbar-brand-font-size, 20px) !important;
}

.tutorial-back-link {
  padding-left: 15px !important;
  font-weight: 650 !important;
}

.tutorial-back-icon {
  margin-right: 10px;
  font-size: 0.9em;
}

.tutorial-navbar-title {
  max-width: min(42vw, 620px);
  margin-left: 5px;
  overflow: hidden;
  color: #ffffff !important;
  font-weight: 750 !important;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.tutorial-navbar-actions {
  display: flex;
  min-height: 45px;
  margin-left: auto;
  padding-right: 16px;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.tutorial-nav-control,
.tutorial-nav-link,
.tutorial-nav-button {
  display: flex;
  gap: 7px;
  min-height: 34px;
  margin: 0;
  padding: 4px 10px;
  font: inherit;
  font-size: 0.95em;
  line-height: 1.2;
  cursor: pointer;
  white-space: nowrap;
}

.tutorial-nav-button {
  border: 0;
  background: none;
}

.tutorial-nav-hidden,
.tvm-toggle-input {
  display: none;
}

.privacy-notice-region {
  max-width: 860px;
  margin: 20px auto 0;
  padding: 0 20px;
  clear: both;
}

.autosave-confirm-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 2000;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.58);
}

.autosave-confirm-panel {
  width: min(100%, 420px);
  padding: 28px 32px;
  border: 1px solid var(--sebook-border);
  border-radius: var(--radius-md, 8px);
  background: var(--sebook-surface);
  box-shadow: var(--sebook-shadow);
  color: var(--color-text, #222);
}

.autosave-confirm-title {
  margin: 0 0 8px;
  color: var(--sebook-navy-dark);
  font-weight: 800;
}

.autosave-confirm-copy,
.autosave-confirm-note {
  line-height: 1.5;
}

.autosave-confirm-copy {
  margin: 0 0 8px;
}

.autosave-confirm-note {
  margin: 0 0 24px;
  color: var(--color-text-muted, #595959);
  font-size: 0.95em;
}

.autosave-confirm-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.autosave-confirm-button {
  min-height: 40px;
  padding: 7px 20px;
  border: 1px solid var(--sebook-border);
  border-radius: var(--radius-sm, 6px);
  background: var(--sebook-surface-soft);
  color: var(--color-text, #222);
  cursor: pointer;
  font: inherit;
  font-weight: 700;
}

.autosave-confirm-button.is-danger {
  border-color: #8f1f18;
  background: #c0392b;
  color: #ffffff;
}

.tts-control-bar {
  display: none;
  position: fixed;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 1050;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  padding: 8px 20px;
  border-top: 4px solid var(--sebook-gold);
  background: #17324d;
  color: #ffffff;
  box-shadow: 0 -8px 24px rgba(0, 0, 0, 0.34);
}

.tts-control-label {
  margin-right: 4px;
  color: #B9D9EB;
  font-size: 0.95em;
  font-weight: 750;
}

.tts-control-button,
.tts-control-select {
  min-height: 34px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-sm, 6px);
  background: rgba(255, 255, 255, 0.09);
  color: #ffffff;
  cursor: pointer;
  font: inherit;
  font-size: 0.92em;
  font-weight: 700;
}

.tts-control-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 4px 11px;
  flex-shrink: 0;
}

.tts-control-button.is-primary,
.tts-control-button.is-square {
  width: 34px;
  padding: 0;
}

.tts-control-button.is-primary {
  border: 2px solid var(--sebook-blue);
  border-radius: var(--radius-circle, 50%);
  background: transparent;
}

.tts-control-button.is-danger {
  margin-left: auto;
  border-color: rgba(220, 80, 80, 0.58);
  background: rgba(200, 50, 50, 0.2);
  color: #ffd0d0;
}

.tts-control-button:hover,
.tts-control-button:focus-visible,
.tts-control-select:hover,
.tts-control-select:focus-visible {
  border-color: var(--sebook-gold);
  background: rgba(255, 209, 0, 0.18);
  color: #ffffff;
}

.tts-control-select {
  max-width: 170px;
  margin-left: 4px;
  padding: 4px 8px;
}

.tts-control-rate {
  min-width: 36px;
  color: #B9D9EB;
  font-size: 0.95em;
  font-weight: 750;
  text-align: center;
}

.tts-control-hidden {
  display: none;
}

#bookmarkBtnWrapper {
  align-items: center;
}

#bookmarkPageBtn {
  min-width: 34px;
  min-height: 34px;
  padding: 0 2px;
  border: 0;
  background: none;
  color: var(--sebook-blue);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3em;
  line-height: 1;
  vertical-align: middle;
}

/* Shared command buttons. Keep icon-only controls and answer options out of this rule. */
.filter-btn,
.btn.btn-default,
.btn.btn-primary,
.btn.btn-success,
.btn.btn-info,
.btn.btn-warning,
.btn.btn-danger,
.btn.btn-clipboard,
.dmbutton,
.settings-btn,
.cookies-btn,
.gym-btn,
.submit-answer-btn,
.next-btn,
.restart-btn,
.review-btn,
.show-answer-btn,
.parsons-check-btn,
.parsons-reset-btn,
.spec-card-btn,
.tvm-btn,
.sbr-btn,
.tvm-debug-watch-add-btn,
.tvm-debug-watchpoint-add-btn,
.tvm-instructions-detached-placeholder .tvm-btn-reattach {
  display: inline-flex;
  align-items: center !important;
  justify-content: center !important;
  gap: 0.45em;
  min-height: 44px;
  padding: 9px 16px !important;
  border: 2px solid var(--sebook-button-border, #2774AE) !important;
  border-radius: var(--radius-md, 8px) !important;
  background: var(--sebook-button-bg, #ffffff) !important;
  color: var(--sebook-button-text, #003B5C) !important;
  box-shadow: 0 3px 8px rgba(0, 59, 92, 0.12);
  cursor: pointer;
  font: inherit;
  font-weight: 750 !important;
  line-height: 1.2;
  letter-spacing: 0;
  text-align: center;
  text-decoration: none !important;
  transition: background-color 0.16s ease, border-color 0.16s ease, color 0.16s ease, box-shadow 0.16s ease, transform 0.16s ease;
}

.filter-btn:hover,
.filter-btn:focus,
.btn.btn-default:hover,
.btn.btn-default:focus,
.btn.btn-clipboard:hover,
.btn.btn-clipboard:focus,
.dmbutton:hover,
.dmbutton:focus,
.settings-btn:hover,
.settings-btn:focus,
.cookies-btn:hover:not(:disabled),
.gym-btn.secondary:hover:not(:disabled),
.parsons-reset-btn:hover:not(:disabled),
.spec-card-btn:hover:not(:disabled),
.tvm-btn:hover:not(:disabled),
.sbr-btn:hover:not(:disabled),
.tvm-instructions-detached-placeholder .tvm-btn-reattach:hover {
  background: var(--sebook-button-bg-hover, #eef7ff) !important;
  border-color: var(--sebook-blue-dark, #1e5c8a) !important;
  color: var(--sebook-button-text, #003B5C) !important;
  box-shadow: 0 5px 13px rgba(0, 59, 92, 0.16);
  text-decoration: none !important;
}

.filter-btn.active,
.btn.btn-default.active,
.btn.btn-primary,
.btn.btn-success,
.btn.btn-info,
.cookies-btn:not(.danger),
.gym-btn.primary,
.submit-answer-btn,
.next-btn,
.restart-btn,
.review-btn,
.show-answer-btn,
.parsons-check-btn,
.spec-card-btn-primary,
.sbr-primary,
.tvm-debug-watch-add-btn,
.tvm-debug-watchpoint-add-btn,
.tvm-btn-prev,
.tvm-btn-next,
.tvm-btn-test {
  background: var(--sebook-button-primary-bg, #2774AE) !important;
  border-color: #005587 !important;
  color: var(--sebook-button-primary-text, #ffffff) !important;
  box-shadow: inset 0 -3px 0 rgba(0, 59, 92, 0.32), 0 4px 10px rgba(0, 59, 92, 0.18);
}

.filter-btn.active::before {
  content: none !important;
  display: none !important;
}

.filter-btn.active:hover,
.filter-btn.active:focus,
.btn.btn-default.active:hover,
.btn.btn-default.active:focus,
.btn.btn-primary:hover,
.btn.btn-primary:focus,
.btn.btn-success:hover,
.btn.btn-success:focus,
.btn.btn-info:hover,
.btn.btn-info:focus,
.cookies-btn:hover:not(.danger):not(:disabled),
.gym-btn.primary:hover:not(:disabled),
.submit-answer-btn:hover:not(:disabled),
.next-btn:hover:not(:disabled),
.restart-btn:hover:not(:disabled),
.review-btn:hover:not(:disabled),
.show-answer-btn:hover:not(:disabled),
.parsons-check-btn:hover:not(:disabled),
.spec-card-btn-primary:hover:not(:disabled),
.sbr-primary:hover:not(:disabled),
.tvm-debug-watch-add-btn:hover:not(:disabled),
.tvm-debug-watchpoint-add-btn:hover:not(:disabled),
.tvm-btn-prev:hover:not(:disabled),
.tvm-btn-next:hover:not(:disabled),
.tvm-btn-test:hover:not(:disabled) {
  background: #1e5c8a !important;
  border-color: #003B5C !important;
  color: #ffffff !important;
}

.btn.btn-warning {
  background: var(--sebook-gold, #FFD100) !important;
  border-color: var(--sebook-gold-dark, #B38B00) !important;
  color: var(--sebook-on-gold, #061d31) !important;
}

.btn.btn-warning:hover,
.btn.btn-warning:focus {
  background: #FFB81C !important;
  border-color: #8a6d00 !important;
  color: #061d31 !important;
}

.gym-btn.danger,
.btn.btn-danger,
.cookies-btn.danger,
.spec-card-btn-danger {
  background: var(--color-error, #b81e2c) !important;
  border-color: #7a111d !important;
  color: #ffffff !important;
}

.gym-btn.danger:hover:not(:disabled),
.btn.btn-danger:hover,
.btn.btn-danger:focus,
.cookies-btn.danger:hover:not(:disabled),
.spec-card-btn-danger:hover:not(:disabled) {
  background: var(--color-error-hover, #94121e) !important;
  border-color: #5f0b16 !important;
  color: #ffffff !important;
}

.filter-btn:disabled,
.btn:disabled,
.cookies-btn:disabled,
.gym-btn:disabled,
.submit-answer-btn:disabled,
.next-btn:disabled,
.restart-btn:disabled,
.review-btn:disabled,
.show-answer-btn:disabled,
.parsons-check-btn:disabled,
.parsons-reset-btn:disabled,
.spec-card-btn:disabled,
.sbr-btn:disabled,
.tvm-debug-watch-add-btn:disabled,
.tvm-debug-watchpoint-add-btn:disabled,
.tvm-btn:disabled {
  background: #dbe7f1 !important;
  border-color: #b9c9d8 !important;
  color: #42617c !important;
  box-shadow: none !important;
  cursor: not-allowed !important;
  opacity: 1 !important;
}

/* Shared tooltip treatment for Bootstrap tooltips and custom inline tooltips. */
.tooltip {
  font-family: inherit;
  font-size: var(--font-size-readable-min, 16px) !important;
  line-height: 1.4;
  opacity: 1 !important;
  z-index: 3000;
}

.tooltip.in {
  opacity: 1 !important;
}

.tooltip-inner,
[role="tooltip"].info-tooltip {
  max-width: min(320px, calc(100vw - 32px));
  padding: 10px 12px;
  border: 2px solid var(--sebook-gold, #FFD100);
  border-radius: var(--radius-md, 8px);
  background: #003B5C;
  color: #ffffff;
  box-shadow: 0 12px 26px rgba(0, 59, 92, 0.26);
  font: inherit;
  font-size: var(--font-size-readable-min, 16px);
  font-weight: 650;
  line-height: 1.4;
  text-align: left;
}

.tooltip.top .tooltip-arrow,
.tooltip.top-left .tooltip-arrow,
.tooltip.top-right .tooltip-arrow {
  border-top-color: #003B5C;
}

.tooltip.right .tooltip-arrow {
  border-right-color: #003B5C;
}

.tooltip.bottom .tooltip-arrow,
.tooltip.bottom-left .tooltip-arrow,
.tooltip.bottom-right .tooltip-arrow {
  border-bottom-color: #003B5C;
}

.tooltip.left .tooltip-arrow {
  border-left-color: #003B5C;
}

[role="tooltip"].info-tooltip::after {
  border-bottom-color: #003B5C;
}

.blog-post-item {
  padding: var(--sp-lg, 16px);
  margin-bottom: var(--sp-xl, 24px);
}

.blog-post-title a,
.blog-post-title a:visited {
  color: var(--sebook-navy-dark);
}

.blog-post-title a:hover,
.blog-post-title a:focus {
  color: var(--sebook-blue-dark);
}

.blog-post-info,
.blog-post-excerpt,
.blog-post-meta {
  color: var(--color-text-muted, #595959);
}

.rounded-img,
.blog-post-header img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md, 8px);
  overflow: hidden;
  box-shadow: var(--sebook-shadow);
}

.blog-post-header {
  margin-bottom: var(--sp-2xl, 30px);
  border-bottom: 1px solid var(--sebook-border);
  padding-bottom: var(--sp-xl, 20px);
}

.blog-post-header h1 {
  margin: 0 0 10px;
  font-size: 2.5em;
  line-height: 1.14;
  color: #17324d;
  font-weight: 800;
  -webkit-text-stroke: 0;
}

.post-category {
  margin-left: 15px;
}

.blog-category-badge,
.blog-category-badge:visited {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  border-radius: var(--radius-pill, 999px);
  background: var(--sebook-gold) !important;
  color: #061d31 !important;
  font-weight: 800;
  padding: 3px 10px;
  text-decoration: none !important;
}

.blog-post-content {
  font-size: 1.05em;
  line-height: 1.8;
  color: var(--color-text, #111);
  margin: var(--sp-2xl, 30px) 0;
}

.blog-post-content h2 {
  color: #17324d;
  margin-top: var(--sp-2xl, 30px);
  margin-bottom: var(--sp-lg, 15px);
  font-weight: 800;
  -webkit-text-stroke: 0;
}

.blog-post-content h3,
.blog-post-content h4 {
  font-weight: 800;
}

.blog-post-content p {
  margin-bottom: 15px;
}

.blog-post-content code {
  background-color: var(--color-surface-3, #f5f5f5);
  padding: 2px 6px;
  border-radius: var(--radius-sm, 4px);
  font-family: var(--font-mono, monospace);
}

.blog-post-content pre {
  background-color: var(--color-surface-3, #f5f5f5);
  padding: var(--sp-lg, 15px);
  border-radius: var(--radius-md, 8px);
  overflow-x: auto;
  max-width: 100%;
}

.blog-post-content img,
.blog-post-content video,
.blog-post-content svg {
  max-width: 100%;
  height: auto;
}

.blog-post-content table {
  display: block;
  max-width: 100%;
  overflow-x: auto;
}

.blog-post-footer {
  border-top: 1px solid var(--sebook-border);
  padding-top: var(--sp-xl, 20px);
  margin-top: var(--sp-3xl, 40px);
}

.blog-back-link {
  margin-top: 20px;
}

.blog-bibliography {
  margin-top: var(--sp-3xl, 40px);
}

.blog-bibliography h3 {
  font-weight: 800;
  margin-bottom: 15px;
}

.blog-bibliography .bibliography {
  list-style-type: none;
  padding-left: 0;
}

.blog-bibliography .bibliography li {
  margin-bottom: 10px;
  line-height: 1.5;
}

.action-box {
  border-left: 10px solid var(--sebook-blue);
  padding: var(--sp-sm, 8px) var(--sp-xl, 20px);
  margin: var(--sp-xl, 20px) 0;
  background:
    linear-gradient(90deg, rgba(255, 209, 0, 0.18), rgba(255, 255, 255, 0.92));
}

.action-box *:last-child {
  margin-bottom: 0;
}

.slider.round:before {
  border-radius: var(--radius-circle, 50%);
}

html.dark-mode .inline-language-switcher,
html.dark-mode .highlight-toggle-container,
html.dark-mode .blog-post-item,
html.dark-mode .panel-default,
html.dark-mode .jumbotron,
html.dark-mode .action-box {
  background: #111827 !important;
  border-color: var(--sebook-border) !important;
  box-shadow: var(--sebook-shadow);
}

html.dark-mode .inline-language-tabs {
  background: #1f2937;
}

html.dark-mode .inline-language-tabs button {
  color: #f9fafb;
}

html.dark-mode .inline-language-tabs button:hover,
html.dark-mode .inline-language-tabs button:focus {
  border-color: var(--sebook-gold);
  background: #18314a;
  color: #ffffff;
  box-shadow: 0 0 0 2px #111827;
}

html.dark-mode .inline-language-tabs button[aria-selected="true"],
html.dark-mode .inline-language-tabs button[aria-selected="true"]:hover,
html.dark-mode .inline-language-tabs button[aria-selected="true"]:focus {
  border-color: var(--sebook-gold);
  background: var(--sebook-gold);
  color: var(--sebook-on-gold) !important;
}

html.dark-mode .inline-language-panel pre:focus,
html.dark-mode #main-content pre[tabindex]:focus {
  box-shadow: 0 0 0 2px #111827;
}

html.dark-mode .blog-post-title a,
html.dark-mode .blog-post-title a:visited {
  color: #B9D9EB !important;
}

html.dark-mode .blog-post-title a:hover,
html.dark-mode .blog-post-title a:focus {
  color: var(--sebook-gold) !important;
}

html.dark-mode .blog-post-info,
html.dark-mode .blog-post-excerpt,
html.dark-mode .blog-post-meta {
  color: #cbd6e2 !important;
}

html.dark-mode .blog-post-header {
  border-bottom-color: var(--sebook-border);
}

html.dark-mode .blog-post-content {
  color: #e5e7eb;
}

html.dark-mode .blog-post-content h2 {
  color: var(--sebook-gold) !important;
}

html.dark-mode .blog-post-content code,
html.dark-mode .blog-post-content pre {
  background-color: #111827;
  border-color: var(--sebook-border);
}

html.dark-mode .action-box {
  background:
    linear-gradient(90deg, rgba(255, 209, 0, 0.14), rgba(17, 24, 39, 0.92)) !important;
  border-left-color: var(--sebook-gold) !important;
  color: #e5e7eb !important;
}

html.dark-mode .filter-btn,
html.dark-mode .btn.btn-default,
html.dark-mode .btn.btn-primary,
html.dark-mode .btn.btn-success,
html.dark-mode .btn.btn-info,
html.dark-mode .btn.btn-warning,
html.dark-mode .btn.btn-danger,
html.dark-mode .btn.btn-clipboard,
html.dark-mode .dmbutton,
html.dark-mode .settings-btn,
html.dark-mode .cookies-btn,
html.dark-mode .gym-btn,
html.dark-mode .submit-answer-btn,
html.dark-mode .next-btn,
html.dark-mode .restart-btn,
html.dark-mode .review-btn,
html.dark-mode .show-answer-btn,
html.dark-mode .parsons-check-btn,
html.dark-mode .parsons-reset-btn,
html.dark-mode .spec-card-btn,
html.dark-mode .tvm-btn,
html.dark-mode .sbr-btn,
html.dark-mode .tvm-debug-watch-add-btn,
html.dark-mode .tvm-debug-watchpoint-add-btn,
html.dark-mode .tvm-instructions-detached-placeholder .tvm-btn-reattach {
  background: var(--sebook-button-bg, #101b28) !important;
  border-color: var(--sebook-button-border, #8BB8E8) !important;
  color: var(--sebook-button-text, #e6f4ff) !important;
  box-shadow: 0 4px 11px rgba(0, 0, 0, 0.32);
}

html.dark-mode .filter-btn:hover,
html.dark-mode .filter-btn:focus,
html.dark-mode .btn.btn-default:hover,
html.dark-mode .btn.btn-default:focus,
html.dark-mode .btn.btn-clipboard:hover,
html.dark-mode .btn.btn-clipboard:focus,
html.dark-mode .dmbutton:hover,
html.dark-mode .dmbutton:focus,
html.dark-mode .settings-btn:hover,
html.dark-mode .settings-btn:focus,
html.dark-mode .cookies-btn:hover:not(:disabled),
html.dark-mode .gym-btn.secondary:hover:not(:disabled),
html.dark-mode .parsons-reset-btn:hover:not(:disabled),
html.dark-mode .spec-card-btn:hover:not(:disabled),
html.dark-mode .tvm-btn:hover:not(:disabled),
html.dark-mode .sbr-btn:hover:not(:disabled),
html.dark-mode .tvm-instructions-detached-placeholder .tvm-btn-reattach:hover {
  background: var(--sebook-button-bg-hover, #17324d) !important;
  border-color: var(--sebook-gold, #FFD100) !important;
  color: #ffffff !important;
}

html.dark-mode .filter-btn.active,
html.dark-mode .btn.btn-default.active,
html.dark-mode .btn.btn-primary,
html.dark-mode .btn.btn-success,
html.dark-mode .btn.btn-info,
html.dark-mode .cookies-btn:not(.danger),
html.dark-mode .gym-btn.primary,
html.dark-mode .submit-answer-btn,
html.dark-mode .next-btn,
html.dark-mode .restart-btn,
html.dark-mode .review-btn,
html.dark-mode .show-answer-btn,
html.dark-mode .parsons-check-btn,
html.dark-mode .spec-card-btn-primary,
html.dark-mode .sbr-primary,
html.dark-mode .tvm-debug-watch-add-btn,
html.dark-mode .tvm-debug-watchpoint-add-btn,
html.dark-mode .tvm-btn-prev,
html.dark-mode .tvm-btn-next,
html.dark-mode .tvm-btn-test {
  background: #2774AE !important;
  color: #ffffff !important;
  border-color: #8BB8E8 !important;
}

html.dark-mode .filter-btn.active:hover,
html.dark-mode .filter-btn.active:focus,
html.dark-mode .btn.btn-default.active:hover,
html.dark-mode .btn.btn-default.active:focus,
html.dark-mode .btn.btn-primary:hover,
html.dark-mode .btn.btn-primary:focus,
html.dark-mode .btn.btn-success:hover,
html.dark-mode .btn.btn-success:focus,
html.dark-mode .btn.btn-info:hover,
html.dark-mode .btn.btn-info:focus,
html.dark-mode .cookies-btn:hover:not(.danger):not(:disabled),
html.dark-mode .gym-btn.primary:hover:not(:disabled),
html.dark-mode .submit-answer-btn:hover:not(:disabled),
html.dark-mode .next-btn:hover:not(:disabled),
html.dark-mode .restart-btn:hover:not(:disabled),
html.dark-mode .review-btn:hover:not(:disabled),
html.dark-mode .show-answer-btn:hover:not(:disabled),
html.dark-mode .parsons-check-btn:hover:not(:disabled),
html.dark-mode .spec-card-btn-primary:hover:not(:disabled),
html.dark-mode .sbr-primary:hover:not(:disabled),
html.dark-mode .tvm-debug-watch-add-btn:hover:not(:disabled),
html.dark-mode .tvm-debug-watchpoint-add-btn:hover:not(:disabled),
html.dark-mode .tvm-btn-prev:hover:not(:disabled),
html.dark-mode .tvm-btn-next:hover:not(:disabled),
html.dark-mode .tvm-btn-test:hover:not(:disabled) {
  background: #1e5c8a !important;
  border-color: var(--sebook-gold, #FFD100) !important;
  color: #ffffff !important;
}

html.dark-mode .btn.btn-warning {
  background: #FFD100 !important;
  border-color: #8BB8E8 !important;
  color: #061d31 !important;
}

html.dark-mode .btn.btn-warning:hover,
html.dark-mode .btn.btn-warning:focus {
  background: #FFB81C !important;
  border-color: #ffffff !important;
  color: #061d31 !important;
}

html.dark-mode .gym-btn.danger,
html.dark-mode .btn.btn-danger,
html.dark-mode .cookies-btn.danger,
html.dark-mode .spec-card-btn-danger {
  background: #ff8585 !important;
  border-color: #ffb3b3 !important;
  color: #0a0a14 !important;
}

html.dark-mode .gym-btn.danger:hover:not(:disabled),
html.dark-mode .btn.btn-danger:hover,
html.dark-mode .btn.btn-danger:focus,
html.dark-mode .cookies-btn.danger:hover:not(:disabled),
html.dark-mode .spec-card-btn-danger:hover:not(:disabled) {
  background: #ffa3a3 !important;
  border-color: #FFD100 !important;
  color: #0a0a14 !important;
}

html.dark-mode .filter-btn:disabled,
html.dark-mode .btn:disabled,
html.dark-mode .cookies-btn:disabled,
html.dark-mode .gym-btn:disabled,
html.dark-mode .submit-answer-btn:disabled,
html.dark-mode .next-btn:disabled,
html.dark-mode .restart-btn:disabled,
html.dark-mode .review-btn:disabled,
html.dark-mode .show-answer-btn:disabled,
html.dark-mode .parsons-check-btn:disabled,
html.dark-mode .parsons-reset-btn:disabled,
html.dark-mode .spec-card-btn:disabled,
html.dark-mode .sbr-btn:disabled,
html.dark-mode .tvm-debug-watch-add-btn:disabled,
html.dark-mode .tvm-debug-watchpoint-add-btn:disabled,
html.dark-mode .tvm-btn:disabled {
  background: #152334 !important;
  border-color: #31455d !important;
  color: #9fb3c8 !important;
}

html.dark-mode .tooltip-inner,
html.dark-mode [role="tooltip"].info-tooltip {
  background: #FFD100;
  border-color: #8BB8E8;
  color: #061d31;
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.42);
}

html.dark-mode .tooltip.top .tooltip-arrow,
html.dark-mode .tooltip.top-left .tooltip-arrow,
html.dark-mode .tooltip.top-right .tooltip-arrow {
  border-top-color: #FFD100;
}

html.dark-mode .tooltip.right .tooltip-arrow {
  border-right-color: #FFD100;
}

html.dark-mode .tooltip.bottom .tooltip-arrow,
html.dark-mode .tooltip.bottom-left .tooltip-arrow,
html.dark-mode .tooltip.bottom-right .tooltip-arrow {
  border-bottom-color: #FFD100;
}

html.dark-mode .tooltip.left .tooltip-arrow {
  border-left-color: #FFD100;
}

html.dark-mode [role="tooltip"].info-tooltip::after {
  border-bottom-color: #FFD100;
}

html.dark-mode .autosave-confirm-panel {
  background: #111827;
  color: #e5e7eb;
}

html.dark-mode .autosave-confirm-title {
  color: #B9D9EB;
}

html.dark-mode .autosave-confirm-note {
  color: #cbd6e2;
}

html.dark-mode .autosave-confirm-button {
  background: #1f2937;
  border-color: var(--sebook-border);
  color: #e6f4ff;
}

html.dark-mode .autosave-confirm-button.is-danger {
  background: #b92b22;
  border-color: #fca5a5;
  color: #ffffff;
}

html.dark-mode .tts-control-bar {
  background: #0b1f33;
  box-shadow: 0 -8px 24px rgba(0, 0, 0, 0.5);
}

html.dark-mode .tts-control-label,
html.dark-mode .tts-control-rate {
  color: #B9D9EB;
}

/* Bootstrap/flex fixes shared by SEBook-like navbars */
@media (min-width: 768px) {
  #navnav .container-fluid {
    display: flex !important;
    flex-wrap: wrap !important;
    align-items: stretch !important;
  }

  #navnav .navbar-header {
    float: none !important;
    flex: 0 0 auto !important;
    display: flex !important;
    align-items: center !important;
  }

  #navnav .navbar-collapse {
    flex: 1 1 0 !important;
    display: flex !important;
    padding: 0 !important;
    border-top: none !important;
    box-shadow: none !important;
    overflow: visible !important;
    align-items: center !important;
  }

  #navnav .navbar-nav {
    float: none !important;
    display: flex !important;
    flex-wrap: wrap !important;
    justify-content: flex-end !important;
    align-items: center !important;
    flex: 1 !important;
    margin: 0 !important;
  }

  #navnav .navbar-nav > li {
    float: none !important;
  }

  #navnav .navbar-nav > li > a {
    padding-top: 5px !important;
    padding-bottom: 5px !important;
  }
}

@media screen and (max-width: 1100px) {
  body.sebook-layout #sidebar-toggle {
    display: block !important;
  }

  body.sebook-layout #sidebar {
    position: fixed !important;
    top: 80px !important;
    left: -260px !important;
    width: 260px !important;
    min-width: 0 !important;
    height: 100vh !important;
    z-index: 999 !important;
    transition: left 0.3s ease !important;
    margin-top: 0 !important;
  }

  body.sebook-layout #sidebar.open {
    left: 0 !important;
  }

  body.sebook-layout #main-content {
    width: 100% !important;
    padding: 15px !important;
    overflow-x: clip;
    min-width: 0 !important;
  }

  body.sebook-layout #main-content .container {
    width: 100% !important;
    padding-left: 10px !important;
    padding-right: 10px !important;
  }

  body.sebook-layout .intro-header {
    margin: 0 0 15px !important;
  }

  body.sebook-layout #main-content pre,
  body.sebook-layout #main-content code,
  body.sebook-layout #main-content .highlight pre {
    max-width: 100%;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
  }

  body.sebook-layout:not(.se-gym-page) #main-content .highlighter-rouge code,
  body.sebook-layout:not(.se-gym-page) #main-content .highlight code {
    display: block;
    max-width: 100%;
    white-space: pre-wrap !important;
    overflow-wrap: anywhere;
    word-break: break-word;
  }

  body.sebook-layout #main-content table {
    display: block;
    max-width: 100%;
    overflow-x: auto;
    overflow-y: clip;
  }

  body.sebook-layout #main-content table th,
  body.sebook-layout #main-content table td {
    min-width: 0;
    overflow-wrap: anywhere;
    word-break: break-word;
  }

  body.sebook-layout #main-content img,
  body.sebook-layout #main-content svg {
    max-width: 100%;
    height: auto;
  }

  body.sebook-layout #main-content .uml-class-diagram-container,
  body.sebook-layout #main-content .uml-sequence-diagram-container,
  body.sebook-layout #main-content .uml-state-diagram-container,
  body.sebook-layout #main-content .uml-component-diagram-container,
  body.sebook-layout #main-content .uml-deployment-diagram-container,
  body.sebook-layout #main-content .uml-usecase-diagram-container,
  body.sebook-layout #main-content .uml-activity-diagram-container {
    max-width: 100%;
    overflow-x: auto;
    overflow-y: hidden;
  }

  body.sebook-layout #main-content .uml-class-diagram-container svg,
  body.sebook-layout #main-content .uml-sequence-diagram-container svg,
  body.sebook-layout #main-content .uml-state-diagram-container svg,
  body.sebook-layout #main-content .uml-component-diagram-container svg,
  body.sebook-layout #main-content .uml-deployment-diagram-container svg,
  body.sebook-layout #main-content .uml-usecase-diagram-container svg,
  body.sebook-layout #main-content .uml-activity-diagram-container svg {
    width: 100% !important;
    max-width: 100% !important;
    overflow: hidden;
  }

  body.sebook-layout #main-content mjx-container {
    display: inline-block !important;
    max-width: 100% !important;
    overflow-x: auto !important;
    overflow-y: hidden !important;
    vertical-align: middle;
  }

  body.sebook-layout #main-content mjx-container[display="true"] {
    display: block !important;
  }
}

@media screen and (max-width: 640px) {
  .info-page-nav .navbar-brand {
    padding-right: 10px;
    padding-left: 10px;
    font-size: var(--font-size-readable-min, 16px) !important;
  }

  body.sebook-combined-layout #main-content.container {
    width: 100%;
    padding-right: 14px;
    padding-left: 14px;
  }

  body.sebook-combined-layout #main-content > .row,
  body.sebook-combined-layout #main-content .row {
    margin-right: 0;
    margin-left: 0;
  }

  body.sebook-combined-layout #main-content,
  body.sebook-combined-layout #main-content > .row,
  body.sebook-combined-layout #main-content section,
  body.sebook-combined-layout #main-content p,
  body.sebook-combined-layout #main-content li,
  body.sebook-combined-layout #main-content a,
  body.sebook-combined-layout #main-content strong,
  body.sebook-combined-layout #main-content em {
    min-width: 0;
    max-width: 100%;
    overflow-wrap: anywhere;
    word-break: normal;
  }

  body.sebook-combined-layout #main-content pre,
  body.sebook-combined-layout #main-content code,
  body.sebook-combined-layout #main-content .highlight pre,
  body.sebook-combined-layout #main-content .highlight code {
    max-width: 100%;
    overflow-wrap: anywhere;
    white-space: pre-wrap;
    word-break: normal;
  }

  body.sebook-combined-layout #main-content table {
    display: block;
    max-width: 100%;
    overflow-x: auto;
  }

  body.sebook-combined-layout #main-content table th,
  body.sebook-combined-layout #main-content table td {
    min-width: 0;
    overflow-wrap: anywhere;
    word-break: break-word;
  }

  body.sebook-combined-layout #main-content img,
  body.sebook-combined-layout #main-content canvas,
  body.sebook-combined-layout #main-content iframe,
  body.sebook-combined-layout #main-content svg {
    max-width: 100% !important;
    height: auto !important;
  }

  body.sebook-combined-layout #main-content .uml-class-diagram-container,
  body.sebook-combined-layout #main-content .uml-sequence-diagram-container,
  body.sebook-combined-layout #main-content .uml-state-diagram-container,
  body.sebook-combined-layout #main-content .uml-component-diagram-container,
  body.sebook-combined-layout #main-content .uml-deployment-diagram-container,
  body.sebook-combined-layout #main-content .uml-usecase-diagram-container,
  body.sebook-combined-layout #main-content .uml-activity-diagram-container {
    max-width: 100%;
    overflow-x: auto;
    overflow-y: hidden;
  }

  body.sebook-combined-layout #main-content .uml-class-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-sequence-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-state-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-component-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-deployment-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-usecase-diagram-container svg,
  body.sebook-combined-layout #main-content .uml-activity-diagram-container svg {
    width: 100% !important;
    max-width: 100% !important;
    overflow: hidden;
  }

  body.sebook-combined-layout #main-content mjx-container {
    display: inline-block !important;
    max-width: 100% !important;
    overflow-x: auto !important;
    overflow-y: hidden !important;
    vertical-align: middle;
  }

  body.sebook-combined-layout #main-content mjx-container[display="true"] {
    display: block !important;
  }

  body.sebook-combined-layout #navnav .navbar-header {
    max-width: 100%;
  }

  body.sebook-combined-layout #navnav .navbar-brand {
    max-width: calc(100vw - 78px);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .inline-language-tabs button {
    flex: 1 1 44%;
  }

  .blog-post-container,
  .blog-post-content,
  .blog-post-content p,
  .blog-post-content li,
  .blog-post-content a,
  .blog-post-content strong,
  .blog-post-content em {
    min-width: 0;
    max-width: 100%;
    overflow-wrap: anywhere;
    word-break: normal;
  }

  .blog-post-header h1 {
    font-size: 2em;
    line-height: 1.2;
    overflow-wrap: anywhere;
  }

  .blog-post-content pre {
    white-space: pre-wrap;
    overflow-wrap: anywhere;
  }

  .blog-post-content code {
    overflow-wrap: anywhere;
    word-break: break-word;
  }

  .blog-post-footer .btn {
    min-height: 24px;
    display: inline-flex;
    align-items: center;
  }
}

/* Readability baseline.
   Bootstrap and a few older widgets ship compact 10-15px defaults. Keep
   task-facing copy and controls at paragraph size while letting larger
   headings keep their hierarchy. */
body.default-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block, .post-meta, .blog-post-info, .blog-post-excerpt, .filter-btn, .dmbutton, .toggle-label, .cookie-notice),
body.blog-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block, .post-meta, .blog-post-info, .blog-post-excerpt, .filter-btn, .dmbutton, .toggle-label, .cookie-notice),
body.framework-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block, .post-meta, .settings-note, .shortcuts-note, .shortcuts-page kbd),
body.sebook-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block, .toggle-label, .blog-post-info, .blog-post-excerpt, .quiz-difficulty, .flashcards-container .quiz-difficulty, .option-feedback, .parsons-label, .parsons-separator, .quiz-option, .settings-note, .shortcuts-note, .shortcuts-page kbd),
body.sebook-combined-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block),
body.tutorial-layout :is(p, li, a, td, th, label, input, textarea, select, button, summary, figcaption, caption, .btn, .form-control, .dropdown-menu, .tooltip, .popover, .alert, .list-group, .breadcrumb, .pagination, .pager, .label, .badge, .help-block) {
  font-size: max(1em, var(--font-size-readable-min, 16px));
}

body.default-layout :is(small, .small),
body.blog-layout :is(small, .small),
body.framework-layout :is(small, .small),
body.sebook-layout :is(small, .small),
body.sebook-combined-layout :is(small, .small),
body.tutorial-layout :is(small, .small) {
  font-size: max(0.95em, var(--font-size-readable-min, 16px));
}

@media (prefers-reduced-motion: reduce) {
  .sebook-nav-link,
  .sebook-nav-sublink,
  .sebook-nav-itemlink,
  .sebook-nav-toggle,
  body.sebook-layout #sidebar {
    transition: none !important;
  }
}

/* ---------------------------------------------------------------- */
/* SE Book homepage search                                           */
/* ---------------------------------------------------------------- */

/* The `display` rules below override the default UA `[hidden] { display: none }`,
   so we need to re-assert it for every element that toggles via `.hidden`. */
.sebook-search-clear[hidden],
.sebook-search-results[hidden],
.sebook-search-result[hidden],
.sebook-search-no-results[hidden] {
  display: none !important;
}

.sebook-search {
  margin: 2em auto;
  padding: 1.4em 1.6em 1.6em;
  background: var(--sebook-surface);
  border: 1px solid var(--sebook-border);
  border-radius: 12px;
  box-shadow: 0 4px 18px rgba(0, 59, 92, 0.07);
  max-width: 900px;
}

html.dark-mode .sebook-search {
  background: var(--sebook-surface);
  border-color: var(--sebook-border);
  box-shadow: 0 6px 22px rgba(0, 0, 0, 0.42);
}

.sebook-search > h2 {
  margin: 0 0 0.6em;
  font-size: 1.4em;
  color: var(--sebook-navy);
}

html.dark-mode .sebook-search > h2 {
  color: var(--sebook-navy);
}

.sebook-search-controls {
  display: flex;
  flex-direction: column;
  gap: 0.5em;
}

.sebook-search-label {
  font-weight: 700;
  color: var(--sebook-navy);
  font-size: 1em;
}

html.dark-mode .sebook-search-label {
  color: var(--sebook-navy);
}

.sebook-search-input-wrap {
  position: relative;
  display: flex;
  align-items: stretch;
}

.sebook-search-input {
  flex: 1;
  width: 100%;
  font: inherit;
  font-size: 1em;
  padding: 0.6em 2.4em 0.6em 0.8em;
  border: 2px solid var(--sebook-button-border);
  border-radius: 8px;
  background: var(--sebook-button-bg);
  color: var(--sebook-button-text);
  box-sizing: border-box;
  min-height: 44px;
}

.sebook-search-input::placeholder {
  color: #5a6f82;
  opacity: 1;
}

html.dark-mode .sebook-search-input::placeholder {
  color: #b8c6d4;
  opacity: 1;
}

.sebook-search-input:focus-visible {
  outline: var(--focus-width, 3px) solid var(--focus-color, #FFD100);
  outline-offset: var(--focus-offset, 2px);
}

.sebook-search-clear {
  position: absolute;
  right: 0.4em;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  min-width: 32px;
  min-height: 32px;
  border: 2px solid var(--sebook-button-border);
  border-radius: 50%;
  background: var(--sebook-button-bg);
  color: var(--sebook-button-text);
  font-size: 1.2em;
  line-height: 1;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}

.sebook-search-clear:hover {
  background: var(--sebook-button-bg-hover);
}

.sebook-search-clear:focus-visible {
  outline: var(--focus-width, 3px) solid var(--focus-color, #FFD100);
  outline-offset: var(--focus-offset, 2px);
}

.sebook-search-hint {
  margin: 0;
  font-size: 0.95em;
  color: var(--sebook-navy);
  opacity: 0.85;
}

.sebook-search-summary {
  margin: 0;
  font-size: 0.95em;
  color: var(--sebook-navy);
  font-weight: 700;
  min-height: 1.4em;
}

.sebook-search-results {
  list-style: none;
  margin: 1em 0 0;
  padding: 0;
  border-top: 1px solid var(--sebook-border);
  max-height: 420px;
  overflow-y: auto;
}

.sebook-search-result {
  border-bottom: 1px solid var(--sebook-border);
  margin: 0;
}

.sebook-search-result-link {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.8em;
  padding: 0.7em 0.6em;
  text-decoration: none;
  color: var(--sebook-button-text);
  border-radius: 6px;
  min-height: 44px;
  flex-wrap: wrap;
}

.sebook-search-result-link:hover {
  background: var(--sebook-button-bg-hover);
  text-decoration: underline;
}

.sebook-search-result-link:focus-visible {
  outline: var(--focus-width, 3px) solid var(--focus-color, #FFD100);
  outline-offset: var(--focus-offset, 2px);
}

html.dark-mode .sebook-search-result-link {
  color: var(--sebook-button-text);
}

html.dark-mode .sebook-search-result-link:hover {
  background: var(--sebook-button-bg-hover);
}

.sebook-search-result-title {
  font-weight: 700;
  flex: 1 1 auto;
}

.sebook-search-result-kind {
  font-size: 0.85em;
  color: #4a5d6f;
  white-space: nowrap;
  flex: 0 0 auto;
}

html.dark-mode .sebook-search-result-kind {
  color: #b8c6d4;
}

.sebook-search-result--subtopic .sebook-search-result-link {
  padding-left: 1.8em;
}

.sebook-search-result--item .sebook-search-result-link {
  padding-left: 3em;
}

.sebook-search-no-results {
  margin: 1em 0 0;
  padding: 1em;
  background: var(--sebook-surface-band);
  border: 1px dashed var(--sebook-border);
  border-radius: 8px;
  color: var(--sebook-navy);
  font-weight: 700;
  text-align: center;
}

html.dark-mode .sebook-search-no-results {
  background: var(--sebook-surface-band);
  border-color: var(--sebook-border);
  color: var(--sebook-navy);
}