/**
 * Universal Button System
 * Comprehensive button components with all variants, sizes, and states
 * Consolidates all button patterns from across the application
 */

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: var(--padding-button);
  border: var(--component-border);
  border-radius: var(--component-radius);
  font-family: var(--font-primary);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  line-height: 1;
  text-decoration: none;
  text-align: center;
  white-space: nowrap;
  vertical-align: middle;
  cursor: pointer;
  user-select: none;
  transition: var(--transition-colors), 
              box-shadow var(--transition-base), 
              transform var(--transition-base);
  position: relative;
  overflow: hidden;
  
  /* Prevent double-click selection */
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
}

.btn:focus {
  outline: none;
  box-shadow: var(--state-focus-ring);
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--component-shadow-md);
}

.btn:active {
  transform: translateY(0);
}

.btn:disabled,
.btn.disabled {
  opacity: var(--state-disabled-opacity);
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

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

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

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

.btn-primary:active:not(:disabled) {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
}

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

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

.btn-secondary:active:not(:disabled) {
  background: var(--color-secondary-dark);
  border-color: var(--color-secondary-dark);
}

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

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

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

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

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

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

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

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

.btn-danger:active:not(:disabled) {
  background: var(--color-danger-dark);
  border-color: var(--color-danger-dark);
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

.btn-ghost:hover:not(:disabled) {
  background: rgba(0, 0, 0, var(--state-hover-opacity));
}

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

.btn-ghost-primary:hover:not(:disabled) {
  background: rgba(220, 53, 69, var(--state-hover-opacity));
}

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

.btn-xs {
  padding: var(--padding-button-sm);
  font-size: var(--text-xs);
  border-radius: var(--component-radius-sm);
}

.btn-sm {
  padding: var(--padding-button-sm);
  font-size: var(--text-xs);
}

.btn-lg {
  padding: var(--space-lg) var(--space-2xl);
  font-size: var(--text-base);
  border-radius: var(--component-radius-lg);
}

.btn-xl {
  padding: var(--space-xl) var(--space-3xl);
  font-size: var(--text-lg);
  border-radius: var(--component-radius-xl);
}

/* ===========================================
   SPECIAL BUTTON TYPES
   =========================================== */

/* Icon-only buttons */
.btn-icon {
  padding: var(--space-md);
  min-width: auto;
  width: auto;
  aspect-ratio: 1;
  border-radius: var(--component-radius);
}

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

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

/* Block buttons */
.btn-block {
  width: 100%;
  justify-content: center;
}

/* Create button (from teams section) */
.btn-create {
  background: rgba(255, 255, 255, 0.2);
  color: var(--text-inverse);
  border: 2px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(10px);
}

.btn-create:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.3);
  border-color: rgba(255, 255, 255, 0.5);
}

/* Copy button */
.copy-btn {
  background: var(--color-info);
  color: var(--text-inverse);
  border: none;
  padding: var(--space-md);
  border-radius: var(--component-radius);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  cursor: pointer;
  transition: var(--transition-colors);
}

.copy-btn:hover {
  background: var(--color-info-hover);
}

/* Format buttons */
.format-btn {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: var(--component-border);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--component-radius-sm);
  font-size: var(--text-sm);
  cursor: pointer;
  transition: var(--transition-colors);
}

.format-btn:hover {
  background: var(--bg-secondary);
}

.format-btn.active {
  background: var(--color-primary);
  color: var(--text-inverse);
  border-color: var(--color-primary);
}

/* ===========================================
   BUTTON STATES
   =========================================== */

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

.btn.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 1rem;
  height: 1rem;
  border: 2px solid currentColor;
  border-radius: 50%;
  border-top-color: transparent;
  animation: spin 0.8s linear infinite;
}

.btn.loading.btn-sm::after {
  width: 0.75rem;
  height: 0.75rem;
}

.btn.loading.btn-lg::after {
  width: 1.25rem;
  height: 1.25rem;
}

/* Pulse animation for special states */
.btn.pulse {
  animation: pulse 2s infinite;
}

@keyframes spin {
  to {
    transform: translate(-50%, -50%) rotate(360deg);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.7;
  }
}

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

.btn-group {
  display: inline-flex;
  align-items: center;
}

.btn-group .btn {
  border-radius: 0;
  margin-right: -1px;
}

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

.btn-group .btn:last-child {
  border-top-right-radius: var(--component-radius);
  border-bottom-right-radius: var(--component-radius);
  margin-right: 0;
}

.btn-group .btn:only-child {
  border-radius: var(--component-radius);
  margin-right: 0;
}

.btn-group .btn:hover,
.btn-group .btn:focus {
  z-index: 1;
}

/* ===========================================
   RESPONSIVE BUTTON BEHAVIORS
   =========================================== */

@media (max-width: 768px) {
  .btn {
    padding: var(--space-sm) var(--space-md);
    font-size: var(--text-sm);
  }
  
  .btn-lg {
    padding: var(--space-md) var(--space-lg);
    font-size: var(--text-sm);
  }
  
  .btn-xl {
    padding: var(--space-lg) var(--space-xl);
    font-size: var(--text-base);
  }
  
  /* Stack buttons vertically on mobile when in groups */
  .btn-group-mobile-stack {
    flex-direction: column;
    width: 100%;
  }
  
  .btn-group-mobile-stack .btn {
    width: 100%;
    margin-right: 0;
    margin-bottom: -1px;
    border-radius: 0;
  }
  
  .btn-group-mobile-stack .btn:first-child {
    border-top-left-radius: var(--component-radius);
    border-top-right-radius: var(--component-radius);
    border-bottom-left-radius: 0;
  }
  
  .btn-group-mobile-stack .btn:last-child {
    border-bottom-left-radius: var(--component-radius);
    border-bottom-right-radius: var(--component-radius);
    border-top-right-radius: 0;
    margin-bottom: 0;
  }
}

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

@media (prefers-reduced-motion: reduce) {
  .btn {
    transition: none;
  }
  
  .btn:hover {
    transform: none;
  }
  
  .btn.loading::after {
    animation: none;
  }
  
  .btn.pulse {
    animation: none;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .btn {
    border-width: 2px;
  }
  
  .btn:focus {
    outline: 3px solid;
    outline-offset: 2px;
  }
}