/* =============================================================================
   BUTTON COMPONENTS — lib/styles/components/buttons.css
   Total Solutions button system
   Phase 2: Integrating unified interaction motion tokens
   ============================================================================= */

/* =============================================================================
   BASE
   ============================================================================= */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: 2.75rem;
  padding: var(--space-3) var(--space-5);
  border: var(--border-width-medium) solid transparent;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-semibold);
  line-height: 1.25;
  letter-spacing: var(--letter-spacing-normal);
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  user-select: none;
  -webkit-user-select: none;
  
  /* Updated to strictly use Phase 0 dynamic interactive tokens */
  transition:
    background-color var(--motion-transition-interactive),
    color var(--motion-transition-interactive),
    border-color var(--motion-transition-interactive),
    box-shadow var(--motion-transition-interactive),
    transform var(--motion-transition-interactive),
    opacity var(--motion-transition-interactive);
}

.btn:hover {
  text-decoration: none;
}

.btn:focus-visible {
  outline: var(--border-width-medium) solid var(--color-primary);
  outline-offset: var(--space-1);
}

.btn:disabled,
.btn.btn--disabled {
  opacity: 0.5;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
  pointer-events: none;
}

.btn--full-width {
  width: 100%;
}

.btn--loading {
  cursor: progress;
  pointer-events: none;
}

.btn__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

.btn__icon--leading {
  margin-right: var(--space-1);
}

.btn__icon--trailing {
  margin-left: var(--space-1);
  transition: transform var(--motion-transition-interactive);
}

.btn:hover .btn__icon--trailing {
  transform: translateX(0.125rem);
}

.btn__label--loading {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
}

/* =============================================================================
   SIZES
   ============================================================================= */

.btn--sm {
  min-height: var(--button-height-sm);
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-body-sm);
}

.btn--md {
  min-height: var(--button-height-md);
  padding: var(--space-3) var(--space-5);
}

.btn--lg {
  min-height: var(--button-height-lg);
  padding: var(--space-4) var(--space-6);
  font-size: var(--font-size-body-lg);
}

/* =============================================================================
   PRIMARY
   Brand guide: Action Blue is the primary CTA color.
   ============================================================================= */

.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

.btn--primary:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  box-shadow: var(--shadow-md);
  transform: translateY(-0.0625rem);
}

.btn--primary:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-primary-active);
  border-color: var(--color-primary-active);
  box-shadow: var(--shadow-sm);
  transform: translateY(0);
}

/* =============================================================================
   SECONDARY
   Trust Navy surface, inverse text.
   ============================================================================= */

.btn--secondary {
  background-color: var(--color-brand-trust-navy);
  color: var(--color-text-inverse);
  border-color: var(--color-brand-trust-navy);
  box-shadow: var(--shadow-sm);
}

.btn--secondary:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-secondary-hover);
  border-color: var(--color-secondary-hover);
  box-shadow: var(--shadow-md);
  transform: translateY(-0.0625rem);
}

.btn--secondary:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-secondary-active);
  border-color: var(--color-secondary-active);
  box-shadow: var(--shadow-sm);
  transform: translateY(0);
}

/* =============================================================================
   OUTLINE
   Checklist requires Action Blue outline variants.
   ============================================================================= */

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

.btn--outline:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(0, 86, 210, 0.06);
  border-color: var(--color-primary-hover);
  color: var(--color-primary-hover);
  transform: translateY(-0.0625rem);
}

.btn--outline:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(0, 86, 210, 0.1);
  border-color: var(--color-primary-active);
  color: var(--color-primary-active);
  transform: translateY(0);
}

/* =============================================================================
   GHOST
   Useful for quiet actions in dense layouts.
   ============================================================================= */

.btn--ghost {
  background-color: transparent;
  border-color: transparent;
  color: var(--color-brand-trust-navy);
}

.btn--ghost:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-surface-subtle);
  color: var(--color-brand-trust-navy);
}

.btn--ghost:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-surface-muted);
}

/* =============================================================================
   DARK SURFACE VARIANTS
   ============================================================================= */

.btn--outline-dark {
  background-color: transparent;
  border-color: var(--color-text-inverse);
  color: var(--color-text-inverse);
}

.btn--outline-dark:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(255, 255, 255, 0.08);
  border-color: var(--color-text-inverse);
  color: var(--color-text-inverse);
  transform: translateY(-0.0625rem);
}

.btn--outline-dark:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(255, 255, 255, 0.12);
  transform: translateY(0);
}

.btn--ghost-dark {
  background-color: transparent;
  border-color: transparent;
  color: var(--color-text-inverse);
}

.btn--ghost-dark:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(255, 255, 255, 0.08);
}

.btn--ghost-dark:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(255, 255, 255, 0.12);
}

/* =============================================================================
   STATUS / DESTRUCTIVE
   ============================================================================= */

.btn--danger {
  background-color: var(--color-danger);
  border-color: var(--color-danger);
  color: var(--color-text-inverse);
}

.btn--danger:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  filter: brightness(0.96);
  box-shadow: var(--shadow-md);
  transform: translateY(-0.0625rem);
}

.btn--danger:active:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  filter: brightness(0.9);
  transform: translateY(0);
}

/* =============================================================================
   SECTION CONTEXT HELPERS
   ============================================================================= */

.section--accent .btn--secondary,
.section--dark .btn--secondary {
  background-color: var(--color-surface-primary);
  border-color: var(--color-surface-primary);
  color: var(--color-brand-trust-navy);
}

.section--accent .btn--secondary:hover:not(:disabled):not(.btn--disabled):not(.btn--loading),
.section--dark .btn--secondary:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: var(--color-surface-subtle);
  border-color: var(--color-surface-subtle);
}

.section--accent .btn--outline,
.section--dark .btn--outline {
  border-color: var(--color-text-inverse);
  color: var(--color-text-inverse);
}

.section--accent .btn--outline:hover:not(:disabled):not(.btn--disabled):not(.btn--loading),
.section--dark .btn--outline:hover:not(:disabled):not(.btn--disabled):not(.btn--loading) {
  background-color: rgba(255, 255, 255, 0.08);
  border-color: var(--color-text-inverse);
  color: var(--color-text-inverse);
}

/* =============================================================================
   RESPONSIVE TWEAKS & REDUCED MOTION
   ============================================================================= */

@media (max-width: 47.9375rem) {
  .btn {
    width: 100%;
  }

  .btn--inline-mobile {
    width: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  .btn, .btn__icon--trailing {
    transition: color var(--motion-transition-interactive), background-color var(--motion-transition-interactive), border-color var(--motion-transition-interactive);
    transform: none !important;
  }
}