@font-face {
  font-family: "Atkinson Hyperlegible";
  font-style: normal;
  font-weight: 400;
  src:
    url("/fonts/atkinson-hyperlegible-latin-400-normal.woff2") format("woff2"),
    url("/fonts/atkinson-hyperlegible-latin-ext-400-normal.woff2") format("woff2");
}

@font-face {
  font-family: "Atkinson Hyperlegible";
  font-style: normal;
  font-weight: 700;
  src:
    url("/fonts/atkinson-hyperlegible-latin-700-normal.woff2") format("woff2"),
    url("/fonts/atkinson-hyperlegible-latin-ext-700-normal.woff2") format("woff2");
}

:root {
  --uc-blue: #003cb3;
  --uc-dark-blue: #00297d;
  --uc-light-blue: #7ab3ff;
  --uc-gold: #ff9100;
  --uc-light-gold: #ffbc66;
  --uc-white: #ffffff;
  --uc-dark-gray: #1a1f2b;
  --uc-light-gray: #a8b4c5;

  --bg-primary: #ffffff;
  --bg-surface: #ffffff;
  --bg-surface-strong: #f1f3f5;
  --bg-subtle: #f8f9fa;
  --text-primary: #222832;
  --text-secondary: #5d6773;
  --border-light: #e5e7eb;
  --border-strong: #d1d5db;
  --shadow-soft: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-strong: 0 4px 12px rgba(0, 60, 179, 0.15);

  --font-sans: "Atkinson Hyperlegible", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  --font-size-base: 16px;

  --radius-xs: 2px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-2xl: 16px;
  --radius-pill: 999px;

  --content-width: 74rem;
  --content-width-wide: 82rem;
  --focus-ring: 0 0 0 3px rgba(255, 145, 0, 0.28);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-primary: #121212;
    --bg-surface: #1e1e1e;
    --bg-surface-strong: #2d2d2d;
    --bg-subtle: #1a1a1a;
    --text-primary: #edf2f8;
    --text-secondary: #c5d0de;
    --border-light: #333333;
    --border-strong: #444444;
    --shadow-soft: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-strong: 0 4px 12px rgba(0, 0, 0, 0.5);
  }
}

html {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.65;
  color-scheme: light dark;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
}

img {
  max-width: 100%;
}

a {
  color: var(--uc-blue);
  text-decoration: none;
  text-underline-offset: 0.2em;
  transition:
    color 0.2s ease,
    border-color 0.2s ease,
    background-color 0.2s ease,
    box-shadow 0.2s ease,
    transform 0.2s ease;
}

a:hover {
  color: var(--uc-gold);
  text-decoration: underline;
}

button,
input,
select,
textarea {
  font: inherit;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
summary:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.sr-only,
.screen-reader-only {
  clip: rect(1px, 1px, 1px, 1px);
  clip-path: inset(50%);
  height: 1px;
  width: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  white-space: nowrap;
}

.content-container,
.content-container-wide {
  width: min(100% - 2rem, var(--content-width));
  margin: 0 auto;
}

.content-container-wide {
  width: min(100% - 2rem, var(--content-width-wide));
}

.site-shell {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-main {
  flex: 1 0 auto;
  padding-bottom: 4rem;
}

.site-layout {
  width: min(100% - 2rem, var(--content-width-wide));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 17rem minmax(0, 1fr);
  gap: 2rem;
  align-items: start;
}

.site-sidebar {
  position: sticky;
  top: 5.35rem;
  align-self: start;
  max-height: calc(100vh - 6rem);
  overflow: auto;
  padding-top: 1.75rem;
}

.site-sidebar__inner {
  border-right: 1px solid var(--border-light);
  padding-right: 1.25rem;
}

.site-sidebar__eyebrow {
  margin: 0 0 1rem;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-sidebar__nav {
  font-size: 0.95rem;
}

.site-sidebar__list,
.site-sidebar__sublist {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-sidebar__item + .site-sidebar__item {
  margin-top: 0.45rem;
}

.site-sidebar__item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-radius: var(--radius-sm);
  transition: background-color 0.15s ease;
}

.site-sidebar__item-header:hover {
  background: var(--bg-subtle);
}

.site-sidebar__link,
.site-sidebar__sublink {
  display: block;
  padding: 0.45rem 0.65rem;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  text-decoration: none;
}

.site-sidebar__item-header .site-sidebar__link {
  flex: 1;
  padding-right: 0;
  border-radius: 0;
  background: transparent !important;
}

.site-sidebar__link {
  font-weight: 700;
}

.site-sidebar__toggle-label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  cursor: pointer;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  margin-right: 0.1rem;
  transition: color 0.15s ease, background-color 0.15s ease;
}

.site-sidebar__toggle-label:hover {
  color: var(--uc-blue);
  background: rgba(0, 60, 179, 0.08); /* highlight on the chevron itself */
}

.site-sidebar__caret {
  width: 1.15rem;
  height: 1.15rem;
  transition: transform 0.2s ease;
}

.site-sidebar__item.is-current .site-sidebar__link,
.site-sidebar__subitem.is-current > .site-sidebar__sublink {
  background: transparent;
  color: var(--uc-blue);
  text-decoration: none;
  font-weight: 700;
}

.site-sidebar__link:hover,
.site-sidebar__sublink:hover {
  background: var(--bg-subtle);
  color: var(--uc-blue);
  text-decoration: none;
}

.site-sidebar__sublist {
  display: none;
  margin-top: 0.3rem;
  margin-left: 0.4rem;
  padding-left: 0.8rem;
  border-left: 1px solid var(--border-light);
}

.site-sidebar__toggle-checkbox:checked ~ .site-sidebar__sublist {
  display: block;
}

.site-sidebar__toggle-checkbox:checked ~ .site-sidebar__item-header .site-sidebar__caret {
  transform: rotate(90deg);
}

.site-sidebar__subitem + .site-sidebar__subitem {
  margin-top: 0.2rem;
}

.site-sidebar__sublink {
  font-size: 0.92rem;
}

.site-content {
  min-width: 0;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  z-index: 1000;
  padding: 0.7rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--uc-gold);
  color: #1a1a1a;
  font-weight: 700;
}

.skip-link:focus {
  top: 1rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid var(--border-light);
  background: color-mix(in srgb, var(--bg-surface) 92%, transparent 8%);
  backdrop-filter: blur(14px);
}

.site-header__inner {
  width: min(100% - 2rem, var(--content-width-wide));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.95rem 0;
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.9rem;
  color: inherit;
  text-decoration: none;
}

.site-brand:hover {
  color: inherit;
  text-decoration: none;
}

.site-brand__mark {
  width: 3rem;
  height: 3rem;
  flex: 0 0 auto;
}

.site-brand__copy {
  min-width: 0;
}

.site-brand__title {
  display: block;
  color: var(--text-primary);
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.1;
}

.site-brand__subtitle {
  display: block;
  color: var(--text-secondary);
  font-size: 0.85rem;
  line-height: 1.2;
}

.site-menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 2.75rem;
  padding: 0.6rem 0.95rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  color: var(--text-primary);
  cursor: pointer;
}

.site-menu-toggle:hover {
  border-color: var(--border-strong);
}

.site-nav {
  display: flex;
  align-items: center;
}

.site-nav__list {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.35rem;
  margin: 0;
  padding: 0;
}

.site-nav__item {
  position: relative;
}

.site-nav__link,
.site-nav__trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  min-height: 2.75rem;
  padding: 0.65rem 0.95rem;
  border: 0;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--text-secondary);
  font-weight: 700;
  font-size: 0.96rem;
  cursor: pointer;
}

.site-nav__link:hover,
.site-nav__trigger:hover,
.site-nav__item.is-current > .site-nav__link,
.site-nav__item.is-current > .site-nav__trigger,
.site-nav__item.is-open > .site-nav__trigger {
  color: var(--uc-blue);
  background: var(--bg-subtle);
  text-decoration: none;
}

.site-nav__item.is-current > .site-nav__link,
.site-nav__item.is-current > .site-nav__trigger {
  box-shadow: inset 0 -2px 0 var(--uc-blue);
}

.site-nav__caret {
  font-size: 0.7rem;
  transition: transform 0.2s ease;
}

.site-nav__item.is-open .site-nav__caret {
  transform: rotate(180deg);
}

.site-nav__menu {
  position: absolute;
  right: 0;
  top: calc(100% + 0.5rem);
  min-width: 15rem;
  padding: 0.5rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  box-shadow: var(--shadow-soft);
  opacity: 0;
  pointer-events: none;
  transform: translateY(-0.35rem);
  transition:
    opacity 0.18s ease,
    transform 0.18s ease;
}

.site-nav__item.is-open .site-nav__menu {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.site-nav__menu-link {
  display: block;
  padding: 0.7rem 0.8rem;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.95rem;
  text-decoration: none;
}

.site-nav__menu-link:hover,
.site-nav__menu-link.is-current {
  background: var(--bg-subtle);
  color: var(--uc-blue);
  text-decoration: none;
}

.site-footer {
  border-top: 1px solid #e0e0e0;
  background: #f5f5f5;
  margin-top: auto;
}

@media (prefers-color-scheme: dark) {
  .site-footer {
    background: #1e1e1e;
    border-top-color: #333333;
  }
}

.site-footer__inner {
  width: min(100% - 2rem, var(--content-width-wide));
  margin: 0 auto;
  padding: 1rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
}

.site-footer__brand {
  display: inline-flex;
  align-items: center;
}

.site-footer__brand img {
  display: block;
  max-width: min(100%, 21rem);
}

.site-footer__brand .logo-light {
  display: none;
}

.site-footer__social {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.site-footer__social-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.4rem;
  height: 2.4rem;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  opacity: 0.72;
}

.site-footer__social-link:hover {
  opacity: 1;
  border-color: var(--border-light);
  background: var(--bg-subtle);
  text-decoration: none;
}

.site-footer__social-link img {
  width: 1.35rem;
  height: 1.35rem;
  display: block;
}

@media (prefers-color-scheme: dark) {
  .site-footer__brand .logo-dark {
    display: none;
  }

  .site-footer__brand .logo-light {
    display: block;
  }

  .site-footer__social-link img {
    filter: invert(1);
  }
}

.page-intro {
  padding: 3rem 0 1.5rem;
}

.page-intro--center {
  text-align: center;
}

.page-intro__eyebrow {
  margin: 0 0 0.75rem;
  color: var(--uc-blue);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.page-intro__title {
  margin: 0;
  color: var(--text-primary);
  font-size: clamp(2rem, 4vw, 3.15rem);
  line-height: 1.08;
  letter-spacing: -0.035em;
}

.page-intro__summary {
  margin: 1rem 0 0;
  max-width: 44rem;
  color: var(--text-secondary);
  font-size: 1.08rem;
}

.page-intro--center .page-intro__summary {
  margin-left: auto;
  margin-right: auto;
}

.page-intro__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 1.5rem;
}

.page-intro--center .page-intro__actions {
  justify-content: center;
}

.breadcrumbs {
  margin-bottom: 1rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.breadcrumbs__separator {
  color: var(--border-strong);
}

.page-section {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: 1.6rem;
}

.page-section + .page-section {
  margin-top: 1.5rem;
}

.section-heading {
  margin: 0 0 1rem;
  color: var(--text-primary);
  font-size: 1.35rem;
}

.section-copy {
  color: var(--text-secondary);
}

.button-primary,
.button-secondary,
.button-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  min-height: 2.85rem;
  padding: 0.8rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  font-weight: 700;
  text-decoration: none;
}

.button-primary {
  background: var(--uc-blue);
  color: var(--uc-white);
}

.button-primary:hover {
  background: var(--uc-gold);
  color: #1a1a1a;
  text-decoration: none;
}

.button-primary[aria-disabled="true"] {
  opacity: 0.45;
  pointer-events: none;
}

.button-secondary {
  border-color: var(--border-light);
  background: var(--bg-surface);
  color: var(--text-primary);
}

.button-secondary:hover {
  border-color: var(--uc-blue);
  color: var(--uc-blue);
  text-decoration: none;
}

.button-link {
  padding-left: 0;
  padding-right: 0;
  color: var(--uc-blue);
}

.button-link:hover {
  color: var(--uc-gold);
  text-decoration: none;
}

.filter-panel {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: 1.35rem;
  margin-bottom: 2rem;
}

.filter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

.filter-field label {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--text-primary);
  font-weight: 700;
}

.filter-input {
  width: 100%;
  min-height: 2.85rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: 0.7rem 0.85rem;
}

.filter-summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.filter-summary p {
  margin: 0;
  color: var(--text-secondary);
}

.lesson-results {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(19rem, 1fr));
  gap: 1.5rem;
}

.empty-state {
  text-align: center;
  color: var(--text-secondary);
  padding: 3rem 1.5rem;
}

.lesson-card {
  position: relative;
  display: flex;
  flex-direction: column;
  height: 100%;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-top: 3px solid var(--uc-blue);
  border-radius: var(--radius-lg);
  box-shadow: none;
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.lesson-card__overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: inherit;
}

.lesson-card__overlay:hover {
  text-decoration: none;
}

.lesson-card:hover {
  box-shadow: var(--shadow-strong);
  border-color: var(--border-strong);
  text-decoration: none;
  color: inherit;
}

.lesson-card__header {
  padding: 1.2rem 1.35rem 1rem;
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border-light);
  position: relative;
  z-index: 2;
  pointer-events: none;
}

.lesson-card__badge-row {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  align-items: center;
  margin-bottom: 1rem;
}

.lesson-card__title-row {
  display: flex;
  gap: 0.8rem;
  align-items: flex-start;
}

.lesson-card__icon {
  font-size: 1.65rem;
  line-height: 1;
  flex: 0 0 auto;
}

.lesson-card__title {
  margin: 0;
  font-size: 1.12rem;
  line-height: 1.35;
  color: var(--text-primary);
}

.lesson-card__body {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 1rem;
  padding: 1.2rem 1.35rem 1.35rem;
  position: relative;
  z-index: 2;
  pointer-events: none;
}

.lesson-card__description,
.lesson-card__meta-copy {
  margin: 0;
  color: var(--text-secondary);
}

.lesson-card__meta-label {
  margin: 0 0 0.4rem;
  color: var(--text-primary);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.lesson-card__link-list {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.lesson-card__link-list a,
.lesson-card__feedback {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  width: fit-content;
  color: var(--uc-blue);
  font-size: 0.92rem;
}

.lesson-card__interactive {
  position: relative;
  z-index: 3;
  pointer-events: auto;
}

.lesson-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.lesson-card__tag {
  display: inline-flex;
  align-items: center;
  min-height: 2rem;
  padding: 0.25rem 0.7rem;
  border-radius: var(--radius-sm);
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  color: var(--text-primary);
  font-size: 0.82rem;
  font-weight: 700;
}

.lesson-card__tag--accent {
  background: rgba(0, 60, 179, 0.08);
  border-color: rgba(0, 60, 179, 0.18);
  color: var(--uc-blue);
}

.lesson-card__tag--warm {
  background: rgba(255, 145, 0, 0.12);
  border-color: rgba(255, 145, 0, 0.22);
  color: #9a5500;
}

.lesson-card__footnote {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-style: italic;
}

.metadata-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.meta-item {
  padding: 0.95rem 1rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  background: var(--bg-subtle);
}

.meta-label {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.meta-value {
  display: block;
  color: var(--text-primary);
  font-weight: 700;
  word-break: break-word;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  gap: 1rem;
}

.related-card {
  display: block;
  padding: 1rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  background: var(--bg-subtle);
}

.related-card:hover {
  border-color: var(--uc-blue);
  text-decoration: none;
}

.related-title {
  margin: 0 0 0.45rem;
  color: var(--text-primary);
  font-size: 1rem;
}

.related-meta {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

@media (max-width: 980px) {
  .site-layout {
    width: 100%;
    grid-template-columns: 1fr;
    gap: 0;
  }

  .site-sidebar {
    display: none;
  }

  .site-menu-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: absolute;
    left: 1rem;
    right: 1rem;
    top: calc(100% + 0.5rem);
    display: none;
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    background: var(--bg-surface);
    box-shadow: var(--shadow-soft);
    padding: 0.75rem;
  }

  .site-nav.is-open {
    display: block;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.35rem;
  }

  .site-nav__link,
  .site-nav__trigger {
    width: 100%;
    justify-content: space-between;
  }

  .site-nav__menu {
    position: static;
    min-width: auto;
    margin-top: 0.35rem;
    border: 0;
    border-left: 2px solid var(--border-light);
    border-radius: 0;
    box-shadow: none;
    padding: 0.2rem 0 0.2rem 0.7rem;
    display: none;
    opacity: 1;
    pointer-events: auto;
    transform: none;
  }

  .site-nav__item.is-open .site-nav__menu {
    display: block;
  }
}

@media (max-width: 768px) {
  .content-container,
  .content-container-wide,
  .site-header__inner,
  .site-footer__inner,
  .site-layout {
    width: min(100% - 1.25rem, var(--content-width-wide));
  }

  .site-brand__title {
    font-size: 0.98rem;
  }

  .site-brand__subtitle {
    font-size: 0.78rem;
  }

  .site-footer__inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .page-intro {
    padding-top: 2.1rem;
  }

  .filter-summary,
  .page-intro__actions {
    align-items: stretch;
  }

  .button-primary,
  .button-secondary {
    width: 100%;
  }

  .metadata-grid {
    grid-template-columns: 1fr;
  }
}