@layer components {
  .page-shell {
    inline-size: 100%;
    max-inline-size: var(--page-shell-width, var(--main-width));
    margin-inline: auto;
  }

  .page-shell--narrow {
    --page-shell-width: 24rem;
  }

  .page-shell--compact {
    --page-shell-width: 40rem;
  }

  .page-shell--wide {
    --page-shell-width: 64rem;
  }

  .stack {
    display: flex;
    flex-direction: column;
    gap: var(--stack-gap, var(--block-space));
  }

  .stack--tight {
    --stack-gap: 0.5rem;
  }

  .stack--roomy {
    --stack-gap: var(--block-space-double);
  }

  .stack > .page-header {
    margin-block-end: 0;
  }

  .cluster {
    display: flex;
    align-items: center;
    gap: var(--cluster-gap, 0.75rem);
    flex-wrap: wrap;
  }

  .toolbar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-wrap: wrap;
  }

  .toolbar .btn {
    min-inline-size: auto;
  }

  .toolbar__status {
    flex: 1 1 12rem;
  }

  .status {
    font-size: var(--text-sm);
  }

  .status--info {
    color: var(--color-ink-medium);
  }

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

  .status--error {
    color: var(--color-negative);
  }

  .split-panes {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--block-space);
    min-block-size: var(--split-panes-min-height, 24rem);
  }

  .split-panes--tall {
    --split-panes-min-height: 36rem;
  }

  .split-panes__pane {
    display: flex;
    flex-direction: column;
    min-block-size: var(--split-pane-min-height, 16rem);
    min-inline-size: 0;
  }

  .split-panes__pane--tall {
    --split-pane-min-height: 24rem;
  }

  .editor-surface {
    flex: 1;
    min-inline-size: 0;
    border: var(--border);
    border-radius: var(--radius-lg);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
  }

  .editor-surface .ace_readonly_region {
    background: color-mix(in srgb, var(--color-warning) 10%, transparent);
    position: absolute;
  }

  .preview-surface {
    flex: 1;
    min-inline-size: 0;
    overflow: auto;
  }

  .is-loading {
    opacity: 0.5;
  }

  .placeholder {
    padding-block: 4rem;
    color: var(--color-ink-light);
    font-style: italic;
    text-align: center;
  }

  .pill {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-block-size: 1.75rem;
    padding-inline: 0.625rem;
    border-radius: 999px;
    font-size: var(--text-sm);
    font-weight: 600;
    line-height: 1;
    white-space: nowrap;
  }

  .pill--positive {
    background: color-mix(in srgb, var(--color-positive) 14%, transparent);
    border: 1px solid color-mix(in srgb, var(--color-positive) 60%, var(--color-border));
    color: var(--color-positive);
  }

  .callout {
    padding: 0.75rem 1rem;
    border: var(--border);
    border-radius: var(--radius-lg);
    font-size: var(--text-sm);
  }

  .callout--muted {
    background: var(--color-surface-alt, var(--color-surface));
    color: var(--color-ink-medium);
  }

  .callout--success {
    background: color-mix(in srgb, var(--color-positive) 10%, transparent);
    border-color: var(--color-positive);
    color: var(--color-positive);
  }

  .callout--error {
    background: color-mix(in srgb, var(--color-negative) 10%, transparent);
    border-color: var(--color-negative);
    color: var(--color-negative);
  }

  .callout--code {
    background: color-mix(in srgb, var(--color-negative) 5%, transparent);
    font-family: var(--font-mono);
    font-size: var(--text-xs, 0.75rem);
    white-space: pre-wrap;
    overflow-x: auto;
  }

  .nav-spread {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    justify-content: space-between;
  }

  .nav-spread .btn {
    min-inline-size: auto;
  }

  .surface-card {
    border: var(--border);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
  }

  .surface-card--padded {
    padding: var(--surface-card-padding, var(--panel-padding));
  }

  @media (max-width: 64rem) {
    .split-panes {
      grid-template-columns: 1fr;
    }
  }

  @media (max-width: 42rem) {
    .toolbar {
      gap: 0.5rem;
    }

    .toolbar .btn {
      flex: 0 0 auto;
      padding-inline: 0.875rem;
    }

    .nav-spread {
      flex-direction: column;
    }

    .nav-spread .btn {
      inline-size: 100%;
    }
  }

  /* Generic header row for side-by-side labels */
  .header-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--block-space);
    align-items: end;
  }

  .header-row__title {
    margin: 0;
    text-align: right;
    font-size: var(--text-lg);
    font-weight: 600;
    line-height: var(--line-tight);
  }

  @media (max-width: 64rem) {
    .header-row {
      grid-template-columns: 1fr;
    }

    .header-row__title {
      display: none;
    }
  }
}