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

header.container {
  text-align: center;
}

header.container .logo {
  max-width: 100%;
  height: auto;
  width: 180px;
}

#assignment-screen article p#problem-prompt {
  font-size: 1.5rem;
  font-weight: bold;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.15em;
}

.frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  vertical-align: middle;
  line-height: 1.3;
  margin: 0 0.15em;
}

.frac .frac-num {
  border-bottom: 2px solid currentColor;
  padding: 0 0.3em 0.1em;
}

.frac .frac-den {
  padding: 0.1em 0.3em 0;
}

#answer-inputs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.frac-input {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
}

.frac-input .frac-input-label {
  font-size: 0.8rem;
  margin: 0;
}

.frac-input input {
  width: 4.5rem;
  text-align: center;
  margin: 0;
}

.frac-bar {
  width: 3.5rem;
  height: 0;
  border: none;
  border-top: 3px solid var(--pico-color);
  margin: 0;
}

.frac-static-den {
  width: 4.5rem;
  text-align: center;
  font-size: 1.25rem;
  font-weight: bold;
}

.whole-and-fraction {
  display: flex;
  align-items: flex-end;
  gap: 0.75rem;
}

#answer-inputs .choice-buttons {
  display: flex;
  gap: 0.5rem;
}

#answer-inputs .choice-buttons button {
  font-size: 1.5rem;
  min-width: 4rem;
}

#feedback.correct {
  color: var(--pico-ins-color, green);
  font-weight: bold;
}

#feedback.wrong {
  color: var(--pico-del-color, crimson);
  font-weight: bold;
}

.error {
  color: var(--pico-del-color, crimson);
}

table td,
table th {
  text-align: center;
}

table td:first-child,
table th:first-child {
  text-align: left;
}