:root {
  color-scheme: light;
  font-family: Inter, system-ui, "Segoe UI", sans-serif;
  color: #112536;
  background: #f3f6f8;
  --accent: #076861;
  --muted: #496070;
  --border: #d9e3e8;
  --surface: #fff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-width: 0;
  line-height: 1.5;
}

.shell {
  width: min(1160px, calc(100% - 64px));
  margin-inline: auto;
}

.masthead {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.masthead-inner {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.wordmark {
  font-size: 1.28rem;
  font-weight: 800;
  letter-spacing: -0.045em;
}

.wordmark span,
a {
  color: var(--accent);
}

a:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 4px;
}

.portal-link,
.youtube-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45em;
  font-size: 0.875rem;
  font-weight: 700;
  text-decoration: none;
}

.portal-link {
  padding-block: 12px;
}

.portal-link:hover {
  text-decoration: underline;
  text-underline-offset: 0.25em;
}

main {
  padding-block: clamp(36px, 5vw, 66px) 56px;
}

.intro {
  margin-bottom: clamp(24px, 3.5vw, 38px);
}

.course-unit {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4rem);
  font-weight: 800;
  letter-spacing: -0.052em;
  line-height: 1.08;
  text-wrap: balance;
}

.summary {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.125rem);
}

.presentation {
  display: grid;
  grid-template-columns: minmax(0, 2.35fr) minmax(270px, 1fr);
  align-items: start;
  gap: 24px;
}

.video-card,
.academic-card {
  border: 1px solid var(--border);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: 0 5px 18px rgb(17 37 54 / 6%);
}

.video-card {
  overflow: hidden;
}

.player {
  position: relative;
  min-height: 200px;
  aspect-ratio: 16 / 9;
  background: #061221;
}

.player iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.player:focus-within {
  outline: 3px solid #33b9ad;
  outline-offset: -3px;
}

.video-actions {
  display: flex;
  justify-content: flex-end;
  padding: 12px 16px;
}

.youtube-link {
  min-height: 44px;
  padding: 0 14px;
  border: 1px solid #c4e4de;
  border-radius: 8px;
  background: #edf8f6;
}

.youtube-link:hover {
  background: #ddf2ee;
}

.academic-card {
  padding: clamp(21px, 2.4vw, 29px);
}

.academic-card h2 {
  margin: 0;
  font-size: 1.28rem;
  line-height: 1.28;
  letter-spacing: -0.022em;
}

.program {
  margin: 7px 0 20px;
  color: var(--muted);
  font-size: 0.9375rem;
}

dl {
  margin: 0;
}

dl > div {
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

dl > div + div {
  margin-top: 16px;
}

dt {
  color: var(--muted);
  font-size: 0.73rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

dd {
  margin: 4px 0 0;
  font-size: 0.9375rem;
  font-weight: 600;
}

@media (max-width: 780px) {
  .shell {
    width: min(660px, calc(100% - 36px));
  }

  .presentation {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }
}