/* Forms.
   .field (+ -hint, -error via :user-invalid or aria-invalid) – labelled input; .field-row (--fields) – fields side by side
   .check – checkbox or radio with label
   .choice – radio chips; .choice-stack – chips as stacked cards with description and price; .swatch – colour dot
   .contact-form-grid, .rail-contact-row – form layouts */
@layer components {
  .field { display: grid; gap: .7rem; }
  .field input, .field textarea, .field select { inline-size: 100%; min-inline-size: 0; min-block-size: 4.4rem; border: .1rem solid var(--line); border-radius: var(--radius); background: var(--paper); color: var(--ink); padding: 1rem; }
  .field textarea { min-block-size: 12rem; resize: vertical; }
  .rail-contact-row { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
  .rail-contact-row > * { min-inline-size: 0; }
  .rail-contact-row label { font-size: var(--small-size); }
  .contact-form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.5rem; }
  .contact-form-grid > * { min-inline-size: 0; }
  .choice { display: flex; flex-wrap: wrap; gap: 1rem; margin-inline: 0; padding: 0; border: 0; }
  .choice input { position: absolute; opacity: 0; inline-size: .1rem; block-size: .1rem; }
  .choice legend { margin-block-end: 1rem; padding: 0; font-weight: 600; }
  .choice label { display: inline-flex; align-items: center; gap: .8rem; min-block-size: 4.4rem; padding: .6rem 1.6rem; border: .1rem solid var(--line); border-radius: var(--radius); background: var(--paper); cursor: pointer; }
  .choice input:checked + label { border-color: var(--accent); box-shadow: inset 0 0 0 .1rem var(--accent); }
  .choice input:focus-visible + label { outline: .25rem solid var(--accent); outline-offset: .3rem; }
  .swatch { inline-size: 2rem; block-size: 2rem; border-radius: 50%; border: .1rem solid var(--line); background: var(--swatch); }
  .field-hint { font-size: var(--small-size); color: var(--muted); }
  .field-error { display: none; font-size: var(--small-size); color: var(--error); }
  .field :is(input, select, textarea):user-invalid, .field [aria-invalid=true] { border-color: var(--error); box-shadow: inset 0 0 0 .1rem var(--error); background: color-mix(in srgb, var(--error) 6%, var(--paper)); }
  .field:has(:user-invalid, [aria-invalid=true]) .field-error:not(:empty) { display: block; }
  .form-status { margin-block: 1rem; }
  .form-status:empty { display: none; }
  .form-status[data-state=error] { color: var(--error); font-weight: 650; padding: 1.2rem; border: .1rem solid var(--error); border-inline-start-width: .4rem; border-radius: var(--radius); background: color-mix(in srgb, var(--error) 8%, var(--paper)); }
  .form-status[data-state=success] { color: var(--success); font-weight: 600; }
  .form-status:focus { outline-offset: .5rem; }
  form button[hidden] { display: none; }
  form[aria-busy=true] button[type=submit]:disabled { cursor: progress; opacity: .7; }
  .field-row { display: grid; grid-template-columns: repeat(var(--fields, 2), minmax(0, 1fr)); gap: 1.6rem; }
  .check { display: flex; align-items: flex-start; gap: 1rem; }
  .check input { inline-size: 2rem; block-size: 2rem; margin: .2rem 0 0; flex: none; accent-color: var(--accent); }
  .choice-stack { display: grid; }
  .choice-stack label { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: .2rem 2rem; padding-block: 1.2rem; }
  .choice-stack label small { grid-column: 1; color: var(--muted); font-size: var(--small-size); }
  .choice-stack label b { grid-column: 2; grid-row: 1; font-weight: 650; }
  @media (width <= 50em) {
    .field-row { --fields: 1; }
    .contact-form-grid { grid-template-columns: minmax(0, 1fr); }
  }
}