/**
 * Snout & About Pet Care - Button Components
 * Version: 1.0.0
 *
 * Comprehensive button component system with variants, sizes, and states.
 * All buttons use design tokens for consistency.
 */

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

.btn {
  /* Layout */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);

  /* Spacing */
  padding: var(--space-3) var(--space-6);

  /* Typography */
  font-family: var(--font-primary);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  line-height: var(--leading-tight);
  text-align: center;
  text-decoration: none;
  white-space: nowrap;

  /* Visual */
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition-fast);
  box-shadow: var(--shadow-sm);

  /* User experience */
  user-select: none;
  -webkit-user-select: none;
  vertical-align: middle;
}

/* Hover State */
.btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  text-decoration: none;
}

/* Focus State (Accessibility) */
.btn:focus-visible {
  outline: none;
  box-shadow: var(--shadow-focus);
  z-index: 1;
}

/* Active State */
.btn:active:not(:disabled) {
  transform: translateY(0);
  box-shadow: var(--shadow-sm);
}

/* Disabled State */
.btn:disabled,
.btn.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  pointer-events: none;
}

/* ============================================
   BUTTON VARIANTS
   ============================================ */

/* Primary Button - Main CTAs */
.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  color: var(--color-text-inverse);
}

.btn-primary:focus-visible {
  box-shadow: var(--shadow-focus);
}

/* Primary Light - Lighter variant */
.btn-primary-light {
  background-color: var(--color-primary-light);
  color: var(--color-text-inverse);
  border-color: var(--color-primary-light);
}

.btn-primary-light:hover:not(:disabled) {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-text-inverse);
}

/* Secondary Button - Secondary actions */
.btn-secondary {
  background-color: var(--color-secondary);
  color: var(--color-text-primary);
  border-color: var(--color-secondary);
}

.btn-secondary:hover:not(:disabled) {
  background-color: var(--color-secondary-hover);
  border-color: var(--color-secondary-hover);
  color: var(--color-text-primary);
}

/* Outline Button - Less prominent actions */
.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
  box-shadow: none;
}

.btn-outline:hover:not(:disabled) {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-sm);
}

/* Outline Secondary */
.btn-outline-secondary {
  background-color: transparent;
  color: var(--color-secondary);
  border-color: var(--color-secondary);
  box-shadow: none;
}

.btn-outline-secondary:hover:not(:disabled) {
  background-color: var(--color-secondary);
  color: var(--color-text-primary);
  box-shadow: var(--shadow-sm);
}

/* Ghost Button - Minimal styling */
.btn-ghost {
  background-color: transparent;
  color: var(--color-primary);
  border-color: transparent;
  box-shadow: none;
}

.btn-ghost:hover:not(:disabled) {
  background-color: rgba(49, 101, 99, 0.08);
  box-shadow: none;
}

/* Light Button - For dark backgrounds */
.btn-light {
  background-color: var(--color-surface);
  color: var(--color-text-primary);
  border-color: var(--color-surface);
}

.btn-light:hover:not(:disabled) {
  background-color: var(--color-background);
  color: var(--color-text-primary);
}

/* ============================================
   SEMANTIC BUTTON VARIANTS
   ============================================ */

/* Success Button */
.btn-success {
  background-color: var(--color-success);
  color: var(--color-text-inverse);
  border-color: var(--color-success);
}

.btn-success:hover:not(:disabled) {
  background-color: var(--color-success-dark);
  border-color: var(--color-success-dark);
  color: var(--color-text-inverse);
}

.btn-success:focus-visible {
  box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.25);
}

/* Warning Button */
.btn-warning {
  background-color: var(--color-warning);
  color: var(--color-text-primary);
  border-color: var(--color-warning);
}

.btn-warning:hover:not(:disabled) {
  background-color: var(--color-warning-dark);
  border-color: var(--color-warning-dark);
  color: var(--color-text-inverse);
}

/* Danger/Error Button */
.btn-danger,
.btn-error {
  background-color: var(--color-error);
  color: var(--color-text-inverse);
  border-color: var(--color-error);
}

.btn-danger:hover:not(:disabled),
.btn-error:hover:not(:disabled) {
  background-color: var(--color-error-dark);
  border-color: var(--color-error-dark);
  color: var(--color-text-inverse);
}

.btn-danger:focus-visible,
.btn-error:focus-visible {
  box-shadow: var(--shadow-focus-error);
}

/* Info Button */
.btn-info {
  background-color: var(--color-info);
  color: var(--color-text-inverse);
  border-color: var(--color-info);
}

.btn-info:hover:not(:disabled) {
  background-color: var(--color-info-dark);
  border-color: var(--color-info-dark);
  color: var(--color-text-inverse);
}

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

/* Extra Small */
.btn-xs {
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
  gap: var(--space-1);
}

/* Small */
.btn-sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
}

/* Default size is already defined in base .btn */

/* Large */
.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-lg);
  gap: var(--space-3);
}

/* Extra Large */
.btn-xl {
  padding: var(--space-5) var(--space-10);
  font-size: var(--text-xl);
  gap: var(--space-3);
}

/* ============================================
   BUTTON SHAPES
   ============================================ */

/* Pill Button */
.btn-pill {
  border-radius: var(--radius-full);
}

/* Square Button */
.btn-square {
  border-radius: var(--radius-sm);
}

/* Circle/Icon-only Button */
.btn-icon {
  padding: var(--space-3);
  aspect-ratio: 1;
  width: auto;
  gap: 0;
}

.btn-icon.btn-sm {
  padding: var(--space-2);
}

.btn-icon.btn-lg {
  padding: var(--space-4);
}

.btn-icon.btn-circle {
  border-radius: var(--radius-full);
}

/* ============================================
   BUTTON GROUPS
   ============================================ */

.btn-group {
  display: inline-flex;
  gap: var(--space-2);
  align-items: center;
}

.btn-group-vertical {
  display: inline-flex;
  flex-direction: column;
  gap: var(--space-2);
  align-items: stretch;
}

/* Attached buttons */
.btn-group-attached {
  display: inline-flex;
  gap: 0;
}

.btn-group-attached .btn {
  border-radius: 0;
}

.btn-group-attached .btn:first-child {
  border-top-left-radius: var(--radius-md);
  border-bottom-left-radius: var(--radius-md);
}

.btn-group-attached .btn:last-child {
  border-top-right-radius: var(--radius-md);
  border-bottom-right-radius: var(--radius-md);
}

.btn-group-attached .btn:not(:last-child) {
  border-right-width: 1px;
}

/* ============================================
   BUTTON STATES & MODIFIERS
   ============================================ */

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

.btn-loading::after {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  top: 50%;
  left: 50%;
  margin-left: -8px;
  margin-top: -8px;
  border: 2px solid currentColor;
  border-top-color: transparent;
  border-radius: 50%;
  animation: btn-spin 0.6s linear infinite;
  color: inherit;
}

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

/* Block Button (full width) */
.btn-block {
  display: flex;
  width: 100%;
}

/* ============================================
   BOOTSTRAP COMPATIBILITY
   ============================================ */

/* Ensure Bootstrap btn classes work with our system */
.btn.btn-primary {
  /* Our custom primary style takes precedence */
}

/* Close button (for modals, alerts) */
.btn-close {
  box-sizing: content-box;
  width: 1em;
  height: 1em;
  padding: 0.25em;
  color: var(--color-text-primary);
  background: transparent url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%23000'%3e%3cpath d='M.293.293a1 1 0 011.414 0L8 6.586 14.293.293a1 1 0 111.414 1.414L9.414 8l6.293 6.293a1 1 0 01-1.414 1.414L8 9.414l-6.293 6.293a1 1 0 01-1.414-1.414L6.586 8 .293 1.707a1 1 0 010-1.414z'/%3e%3c/svg%3e") center/1em auto no-repeat;
  border: 0;
  border-radius: var(--radius-sm);
  opacity: 0.5;
  cursor: pointer;
  transition: var(--transition-fast);
}

.btn-close:hover {
  opacity: 0.75;
}

.btn-close:focus {
  outline: none;
  box-shadow: var(--shadow-focus);
  opacity: 1;
}

/* White close button for dark backgrounds */
.btn-close-white {
  filter: invert(1) grayscale(100%) brightness(200%);
}

/* ============================================
   ICON BUTTONS
   ============================================ */

/* Button with icon on left */
.btn i.fa,
.btn i.fas,
.btn i.fab,
.btn i.bi {
  margin-right: var(--space-1);
}

/* Button with icon on right */
.btn i.fa-right,
.btn i.icon-right {
  margin-right: 0;
  margin-left: var(--space-1);
}

/* Icon-only button - no margin */
.btn-icon i {
  margin: 0;
}

/* ============================================
   RESPONSIVE ADJUSTMENTS
   ============================================ */

@media (max-width: 767.98px) {
  /* Make buttons more touch-friendly on mobile */
  .btn {
    min-height: 44px; /* WCAG touch target size */
    padding: var(--space-3) var(--space-5);
  }

  .btn-sm {
    min-height: 40px;
  }

  /* Stack button groups vertically on mobile */
  .btn-group-mobile-stack {
    flex-direction: column;
  }

  .btn-group-mobile-stack .btn {
    width: 100%;
  }
}

/* ============================================
   ACCESSIBILITY ENHANCEMENTS
   ============================================ */

/* Ensure focus is visible for keyboard users */
.btn:focus:not(:focus-visible) {
  outline: none;
  box-shadow: none;
}

.btn:focus-visible {
  outline: 2px solid transparent;
  outline-offset: 2px;
  box-shadow: var(--shadow-focus);
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .btn {
    border-width: 2px;
  }

  .btn:focus-visible {
    outline: 2px solid currentColor;
  }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  .btn {
    transition: none;
  }

  .btn:hover {
    transform: none;
  }

  .btn-loading::after {
    animation: none;
  }
}