.checkoutDetailsPopup {
    align-items: stretch;
    padding: 0;
  }

  .checkoutDetailsPanel {
    width: 100%;
    max-width: 32rem;
    max-height: none;
  }

  .checkoutDetailsHeader {
    padding: 1rem;
    border-bottom: var(--one-px) solid var(--colour-border-gray);
  }

  .checkoutDetailsHeader h2 {
    margin: 0;
  }

  .checkoutDetailsBody {
    flex: 1 1 auto;
    overflow-y: auto;
    padding: 1rem;
  }

  .checkoutDetailsForm {
    gap: 1.5rem;
  }

  .checkoutDetailsForm fieldset {
    min-width: 0;
    padding: 0 0 1.5rem;
    border: 0;
    border-bottom: var(--one-px) solid var(--colour-border-gray);
  }

  .checkoutDetailsForm fieldset:last-of-type {
    padding-bottom: 0;
    border-bottom: 0;
  }

  .checkoutDetailsForm fieldset[hidden] {
    display: none;
  }

  .checkoutDetailsForm legend {
    margin-bottom: 1rem;
    font-weight: 700;
  }

  .checkoutDetailsForm > button {
    width: 100%;
  }