/* OpenClass: a small online class app used as the CurbCut demo fixture. */

:root {
  --oc-text: #1b1b1f;
  --oc-muted: #4a4a55;
  --oc-bg: #ffffff;
  --oc-surface: #f3f5f9;
  --oc-accent: #0b57d0;
  --oc-accent-dark: #083f96;
  --oc-focus: #b3261e;
  --oc-radius: 6px;
}

* {
  box-sizing: border-box;
}

html {
  font-size: 100%;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.5;
  color: var(--oc-text);
  background: var(--oc-bg);
}

a {
  color: var(--oc-accent);
}

a:hover {
  color: var(--oc-accent-dark);
}

:focus-visible {
  outline: 3px solid var(--oc-focus);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  padding: 0.5rem 1rem;
  background: var(--oc-bg);
  color: var(--oc-accent);
  z-index: 10;
}

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

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.site-header {
  background: var(--oc-surface);
  padding: 1rem 1.5rem;
}

.site-header .brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--oc-text);
  text-decoration: none;
}

.site-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  list-style: none;
  margin: 0.5rem 0 0;
  padding: 0;
}

.site-nav a[aria-current="page"] {
  font-weight: 700;
  color: var(--oc-text);
}

main {
  max-width: 60rem;
  margin: 0 auto;
  padding: 1.5rem;
}

.course-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1rem;
  list-style: none;
  padding: 0;
}

.course-card {
  background: var(--oc-surface);
  border-radius: var(--oc-radius);
  padding: 1rem;
}

.course-card h3 {
  margin-top: 0;
}

.meta {
  color: var(--oc-muted);
  font-size: 0.95rem;
}

.lesson-list {
  padding-left: 1.25rem;
}

.lesson-list li {
  margin-bottom: 0.5rem;
}

.lesson-figure {
  margin: 1.5rem 0;
}

.lesson-figure img {
  max-width: 100%;
  height: auto;
}

.lesson-figure figcaption {
  color: var(--oc-muted);
  font-size: 0.95rem;
}

.btn {
  display: inline-block;
  min-height: 2.75rem;
  padding: 0.6rem 1.2rem;
  border: 0;
  border-radius: var(--oc-radius);
  font: inherit;
  cursor: pointer;
}

.btn-primary {
  background: var(--oc-accent);
  color: #ffffff;
}

.btn-primary:hover {
  background: var(--oc-accent-dark);
}

.status {
  margin-top: 0.75rem;
  color: var(--oc-text);
}

.site-footer {
  max-width: 60rem;
  margin: 2rem auto 0;
  padding: 1rem 1.5rem 2rem;
  color: var(--oc-muted);
}

/* Lesson media */

.media-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.media-card {
  margin: 0;
}

.media-card figcaption {
  color: var(--oc-muted);
  font-size: 0.95rem;
}

.divider {
  display: block;
  max-width: 100%;
  margin: 1.5rem 0;
  animation: divider-fade 6s ease-in-out infinite alternate;
}

@keyframes divider-fade {
  from { opacity: 1; }
  to { opacity: 0.6; }
}

@media (prefers-reduced-motion: reduce) {
  .divider {
    animation: none;
  }
}

.photo-figure {
  display: inline-block;
  margin: 0 0 1rem;
}

.photo-figure img {
  display: block;
}

.figure-caption {
  background: #7fb3d5;
  color: #ffffff;
  padding: 0.4rem 0.6rem;
  font-size: 0.9rem;
}

.key-point {
  height: 44px;
  overflow: hidden;
  background: var(--oc-surface);
  border-radius: var(--oc-radius);
  padding: 0 0.75rem;
}

.key-point p {
  font-size: 14px;
  line-height: 20px;
  margin: 2px 0;
}

.carousel {
  background: var(--oc-surface);
  border-radius: var(--oc-radius);
  padding: 0.5rem 1rem;
  min-height: 3.5rem;
}

.data-table {
  border-collapse: collapse;
  margin-bottom: 1rem;
}

.data-table td,
.data-table th {
  padding: 0.35rem 0.75rem;
  text-align: left;
  background: var(--oc-surface);
}

.data-table caption {
  text-align: left;
  font-weight: 600;
  padding-bottom: 0.25rem;
}

.accordion-trigger {
  display: inline-block;
  color: var(--oc-accent);
  text-decoration: underline;
  cursor: pointer;
  margin-bottom: 0.5rem;
}

.practice {
  border: 1px solid #6b6b76;
  max-width: 100%;
}

.further li {
  margin-bottom: 0.35rem;
}