.button {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: var(--radius-small);
  padding: 0.65rem 1rem;
  font-weight: 800;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  transition: transform 120ms ease, background-color 120ms ease, border-color 120ms ease;
}

.button:active {
  transform: translateY(1px);
}

.button-primary {
  color: #f8fbfa;
  background: #0c665c;
}

.button-primary:hover {
  color: #f8fbfa;
  background: #084c45;
}

.button-secondary {
  border-color: var(--brand);
  color: var(--brand);
  background: var(--surface);
}

.button-secondary:hover {
  color: var(--brand-hover);
  border-color: var(--brand-hover);
  background: var(--surface-muted);
}

.button-quiet {
  border-color: var(--border);
  color: var(--ink);
  background: transparent;
}

.text-link {
  color: var(--brand);
  font-weight: 800;
}

.segmented-control {
  display: inline-flex;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-small);
  padding: 0.18rem;
  background: var(--surface);
}

.segmented-control button,
.utility-controls button {
  min-height: 2.25rem;
  border: 1px solid transparent;
  border-radius: calc(var(--radius-small) - 0.15rem);
  padding: 0.35rem 0.65rem;
  background: transparent;
  font-size: 0.88rem;
  font-weight: 800;
}

.segmented-control button[aria-pressed="true"],
.utility-controls button[aria-pressed="true"] {
  color: #f8fbfa;
  background: #0c665c;
}

.stage-card,
.unit-card,
.lesson-card,
.skills-grid article,
.teacher-resource-grid article {
  border: 1px solid var(--border);
  border-radius: var(--radius-large);
  background: var(--surface);
}

.stage-card {
  display: grid;
  min-height: 17rem;
  grid-template-columns: auto 1fr;
  align-items: end;
  gap: var(--space-5);
  padding: var(--space-6);
  overflow: hidden;
}

.stage-card h3 {
  font-size: 1.65rem;
}

.stage-card h3 a {
  color: var(--ink);
  text-decoration: none;
}

.stage-code {
  display: grid;
  width: 4.5rem;
  height: 4.5rem;
  place-items: center;
  border-radius: var(--radius);
  color: #f8fbfa;
  font-size: 2.25rem;
  font-weight: 900;
}

.stage-foundation .stage-code {
  background: #0c665c;
}

.stage-development .stage-code {
  background: #2d5392;
}

.stage-progression .stage-code {
  background: #69436d;
}

.unit-card,
.teacher-resource-grid article {
  padding: var(--space-6);
}

.unit-card {
  display: flex;
  min-height: 17rem;
  flex-direction: column;
}

.unit-card .button,
.unit-card .muted {
  align-self: flex-start;
  margin-top: auto;
}

.card-topline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}

.unit-code,
.lesson-code {
  color: var(--ink-soft);
  font-size: 0.8rem;
  font-weight: 900;
  letter-spacing: 0.07em;
}

.status-badge {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  border: 1px solid currentColor;
  border-radius: 999px;
  padding: 0.18rem 0.55rem;
  font-size: 0.78rem;
  font-weight: 800;
}

.status-available {
  color: var(--success);
}

.status-coming-soon {
  color: var(--ink-soft);
}

.lesson-card {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: var(--space-5);
  padding: var(--space-5);
}

.lesson-card.is-available {
  border-color: var(--foundation);
  box-shadow: var(--shadow);
}

.lesson-number {
  display: grid;
  width: 4.5rem;
  height: 4.5rem;
  place-items: center;
  border-radius: var(--radius);
  color: var(--brand);
  background: var(--brand-soft);
  font-size: 1.35rem;
  font-weight: 900;
}

.skills-grid article {
  padding: var(--space-5);
}

.skills-grid article > span {
  display: grid;
  width: 2.75rem;
  height: 2.75rem;
  place-items: center;
  margin-bottom: var(--space-4);
  border-radius: var(--radius-small);
  color: #f8fbfa;
  background: #0c665c;
  font-weight: 900;
}

.check-list {
  padding: 0;
  list-style: none;
  columns: 2;
  column-gap: var(--space-5);
}

.check-list li {
  break-inside: avoid;
}

.check-list li::before {
  margin-inline-end: var(--space-2);
  color: var(--success);
  content: "✓";
  font-weight: 900;
}

.empty-state {
  max-width: 48rem;
  margin-block: var(--space-8);
  padding: var(--space-7);
  border: 1px solid var(--border);
  border-radius: var(--radius-large);
  background: var(--surface);
}

.coming-soon-lesson {
  min-height: 28rem;
}

.activity-feedback {
  min-height: 1.8rem;
  margin-top: var(--space-4);
  font-weight: 800;
}

.activity-feedback.is-success {
  color: var(--success);
}

.activity-feedback.is-error {
  color: var(--error);
}

[aria-invalid="true"] {
  border-color: var(--error) !important;
}

.is-correct {
  border-color: var(--success) !important;
}

.quiz-question.is-correct {
  border-left: 0.25rem solid var(--success);
  padding-left: var(--space-4);
}

.quiz-question.is-incorrect {
  border-left: 0.25rem solid var(--error);
  padding-left: var(--space-4);
}

@media (max-width: 48rem) {
  .stage-card,
  .lesson-card {
    grid-template-columns: 1fr;
  }

  .stage-card {
    min-height: auto;
  }

  .check-list {
    columns: 1;
  }

  .button {
    white-space: normal;
  }
}