@layer components {
  /* Button component - refined with depth and micro-interactions */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-lg);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.9375rem;
    border: none;
    cursor: pointer;
    text-decoration: none;
    position: relative;
    transition:
      transform var(--duration-fast) var(--ease-out),
      box-shadow var(--duration-fast) var(--ease-out),
      background-color var(--duration-fast) var(--ease-out),
      border-color var(--duration-fast) var(--ease-out);
  }

  .btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
  }

  /* Focus ring with smooth transition */
  .btn:focus-visible {
    outline: none;
    box-shadow:
      0 0 0 2px var(--color-bg),
      0 0 0 4px var(--color-primary);
  }

  .btn--primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-sm), inset 0 1px 0 oklch(100% 0 0 / 0.15);
  }

  .btn--primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md), var(--shadow-primary-sm), inset 0 1px 0 oklch(100% 0 0 / 0.15);
  }

  .btn--primary:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
    box-shadow: var(--shadow-xs), inset 0 2px 4px oklch(0% 0 0 / 0.1);
  }

  .btn--secondary {
    background-color: var(--color-bg-elevated);
    color: var(--color-text);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-xs);
  }

  .btn--secondary:hover:not(:disabled) {
    background-color: var(--color-bg-muted);
    border-color: var(--color-text-light);
    box-shadow: var(--shadow-sm);
    transform: translateY(-1px);
  }

  .btn--secondary:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
    box-shadow: inset 0 1px 2px oklch(0% 0 0 / 0.05);
  }

  .btn--ghost {
    background-color: transparent;
    color: var(--color-primary);
  }

  .btn--ghost:hover:not(:disabled) {
    background-color: var(--color-primary-subtle);
    transform: translateY(-1px);
  }

  .btn--ghost:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
    background-color: var(--color-primary-muted);
  }

  .btn--danger {
    background: linear-gradient(135deg, var(--color-error) 0%, oklch(45% 0.22 25) 100%);
    color: white;
    box-shadow: var(--shadow-sm);
  }

  .btn--danger:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
  }

  .btn--danger:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
    box-shadow: var(--shadow-xs), inset 0 2px 4px oklch(0% 0 0 / 0.1);
  }

  .btn--outline-danger {
    background: transparent;
    color: var(--color-error);
    border: 1px solid var(--color-error);
  }

  .btn--outline-danger:hover:not(:disabled) {
    background: oklch(97% 0.02 25);
    transform: translateY(-1px);
  }

  .btn--outline-danger:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
    background: oklch(95% 0.04 25);
  }

  .btn--sm {
    padding: var(--space-xs) var(--space-md);
    font-size: 0.8125rem;
    border-radius: var(--radius-sm);
  }

  .btn--lg {
    padding: var(--space-md) var(--space-xl);
    font-size: 1rem;
    border-radius: var(--radius-lg);
  }

  /* Icon Button */
  .btn--icon {
    padding: var(--space-sm);
    background: transparent;
    border: none;
    cursor: pointer;
    color: var(--color-text-muted);
    transition:
      color var(--duration-fast) var(--ease-out),
      transform var(--duration-fast) var(--ease-out);
  }

  .btn--icon:hover {
    color: var(--color-text);
    transform: scale(1.1);
  }

  .btn--favorite-active {
    color: var(--color-primary);
  }

  .btn--favorite-active:hover {
    color: var(--color-primary);
  }

  /* Small button variant */
  .btn--small {
    padding: var(--space-xs) var(--space-md);
    font-size: 0.8125rem;
    border-radius: var(--radius-sm);
  }

  /* Loading state */
  .btn--loading {
    position: relative;
    color: transparent !important;
    pointer-events: none;
  }

  .btn--loading::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    width: 1em;
    height: 1em;
    margin-top: -0.5em;
    margin-left: -0.5em;
    border: 2px solid currentColor;
    border-right-color: transparent;
    border-radius: 50%;
    animation: btn-spinner 0.6s linear infinite;
  }

  .btn--primary.btn--loading::after {
    border-color: white;
    border-right-color: transparent;
  }

  @keyframes btn-spinner {
    to {
      transform: rotate(360deg);
    }
  }

  /* Back link - reusable navigation link with arrow */
  .back-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    color: var(--color-text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--space-md);
    transition: color var(--transition-fast);
  }

  .back-link:hover {
    color: var(--color-primary);
  }
}