@layer components {
  .app-layout .btn,
  #modal .btn {
    min-height: var(--btn-height);
    height: var(--btn-height);
    padding: 0 var(--btn-px);
    border-radius: var(--radius-md);
    border: 1px solid #cbd5e1;
    background: #f8fafc;
    color: var(--ui-text);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    font-size: 13px;
    font-weight: 600;
    line-height: 1;
    white-space: nowrap;
    cursor: pointer;
    transition: background-color 120ms ease, border-color 120ms ease, transform 120ms ease, opacity 120ms ease, box-shadow 120ms ease;
  }

  .app-layout .btn:hover:not(:disabled),
  #modal .btn:hover:not(:disabled) {
    transform: translateY(-1px);
    border-color: #94a3b8;
    background: #f1f5f9;
  }

  .app-layout .btn:active:not(:disabled),
  #modal .btn:active:not(:disabled) {
    transform: translateY(0);
  }

  .app-layout .btn:focus-visible,
  #modal .btn:focus-visible {
    outline: 2px solid var(--ui-focus);
    outline-offset: 2px;
  }

  .app-layout .btn:disabled,
  #modal .btn:disabled {
    opacity: 0.62;
    cursor: not-allowed;
    transform: none;
  }

  .app-layout .btn.primary,
  .app-layout .btn-primary,
  #modal .btn.primary,
  #modal .btn-primary {
    border-color: var(--color-primary);
    background: var(--color-primary);
    color: #ffffff;
    box-shadow: 0 1px 2px rgba(37, 99, 235, 0.24);
  }

  .app-layout .btn.primary:hover:not(:disabled),
  .app-layout .btn-primary:hover:not(:disabled),
  #modal .btn.primary:hover:not(:disabled),
  #modal .btn-primary:hover:not(:disabled) {
    border-color: #1d4ed8;
    background: #1d4ed8;
  }

  .app-layout .btn.secondary,
  .app-layout .btn-secondary,
  .app-layout .btn:not(.primary):not(.btn-primary):not(.danger):not(.btn-danger):not(.ghost):not(.btn-ghost),
  #modal .btn.secondary,
  #modal .btn-secondary,
  #modal .btn:not(.primary):not(.btn-primary):not(.danger):not(.btn-danger):not(.ghost):not(.btn-ghost) {
    border-color: #cbd5e1;
    background: #f8fafc;
    color: #334155;
  }

  .app-layout .btn.danger,
  .app-layout .btn-danger,
  #modal .btn.danger,
  #modal .btn-danger {
    border-color: var(--color-danger);
    background: var(--color-danger);
    color: #fff;
  }

  .app-layout .btn.ghost,
  .app-layout .btn-ghost,
  #modal .btn.ghost,
  #modal .btn-ghost {
    border-color: #cbd5e1;
    background: #ffffff;
    color: #334155;
  }

  .app-layout .btn-xs,
  .app-layout .btn.btn-xs,
  .app-layout .btn.small,
  .app-layout .btn-sm,
  .app-layout .btn.btn-sm,
  #modal .btn-xs,
  #modal .btn.btn-xs,
  #modal .btn.small,
  #modal .btn-sm,
  #modal .btn.btn-sm {
    min-height: var(--btn-height-sm);
    height: var(--btn-height-sm);
    padding: 0 var(--btn-px-sm);
    font-size: 12px;
  }

  .app-layout .quick-add-btn,
  .app-layout .order-more-trigger,
  .app-layout .notification-read-btn,
  .app-layout .product-actions-cell .btn,
  .app-layout .order-actions .btn,
  #modal .quick-add-btn,
  #modal .order-more-trigger,
  #modal .notification-read-btn,
  #modal .product-actions-cell .btn,
  #modal .order-actions .btn {
    min-height: var(--btn-height-sm);
  }

  body.dark .app-layout .btn.secondary,
  body.dark .app-layout .btn-secondary,
  body.dark
    .app-layout
    .btn:not(.primary):not(.btn-primary):not(.danger):not(.btn-danger):not(.ghost):not(.btn-ghost) {
    border-color: var(--border);
    background: #1e293b;
    color: var(--text);
  }

  body.dark .app-layout .btn.secondary:hover:not(:disabled),
  body.dark .app-layout .btn-secondary:hover:not(:disabled),
  body.dark
    .app-layout
    .btn:not(.primary):not(.btn-primary):not(.danger):not(.btn-danger):not(.ghost):not(.btn-ghost):hover:not(:disabled) {
    border-color: #64748b;
    background: #334155;
  }

  body.dark .app-layout .btn.ghost,
  body.dark .app-layout .btn-ghost {
    background: transparent;
    color: var(--text);
    border-color: var(--border);
  }

  /* Source-of-truth: primary luôn có nền + chữ (unlayered style.css có thể làm invalid background). */
  .btn.primary,
  button.btn.primary {
    background: linear-gradient(120deg, var(--primary, #3b82f6), var(--primary-strong, #2563eb)) !important;
    color: #fff !important;
    -webkit-text-fill-color: #fff !important;
    border-color: transparent !important;
    opacity: 1 !important;
    font-weight: 700;
  }

  .btn.primary:disabled,
  button.btn.primary:disabled {
    opacity: 0.62 !important;
    cursor: not-allowed;
  }
}