:root {
  --master-ink: #17353b;
  --master-teal: #0d7471;
  --master-gold: #e9a82d;
  --master-paper: #fffdf6;
}

.master-overview {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin: 30px 0 42px;
}

.master-stat {
  min-height: 132px;
  padding: 22px;
  border: 2px solid var(--master-ink);
  border-radius: 18px;
  background: var(--master-paper);
  box-shadow: 5px 6px 0 rgba(23, 53, 59, .13);
  color: #5d7073;
}

.master-stat p {
  margin: 0;
  background: transparent;
  border: 0;
  padding: 0;
}

.master-stat strong {
  display: block;
  margin-bottom: 8px;
  color: var(--master-teal);
  font-size: clamp(25px, 3vw, 38px);
  line-height: 1;
}

nav#TOC {
  max-height: calc(100vh - 34px);
  overflow-y: auto;
  scrollbar-width: thin;
}

nav#TOC > ul > li > a {
  color: var(--master-ink);
  font-weight: 850;
}

.back-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 40;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 48px;
  min-height: 48px;
  padding: 0 15px;
  border: 2px solid var(--master-ink);
  border-radius: 999px;
  background: var(--master-gold);
  color: var(--master-ink);
  font-weight: 900;
  text-decoration: none;
  box-shadow: 4px 5px 0 rgba(23, 53, 59, .2);
}

.back-top:hover,
.back-top:focus-visible {
  transform: translateY(-2px);
  text-decoration: none;
}

@media (max-width: 900px) {
  .master-overview {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 560px) {
  .master-overview {
    grid-template-columns: 1fr;
  }

  .back-top {
    right: 14px;
    bottom: 14px;
  }
}

@media print {
  .back-top,
  .course-back-to-index {
    display: none !important;
  }
}