/* ==========================================================================
   Components - Unified Component Styles
   
   This file contains all component styles for the design system.
   All styles MUST reference design tokens from variables.css exclusively.
   
   Components:
   - Buttons (Requirements: 3.1, 3.2, 3.3, 3.6)
   - Icons (Requirements: 4.1, 4.2, 4.3, 4.5)
   - Forms (Requirements: 5.1, 5.2, 5.4, 5.5)
   - Cards (Requirements: 6.1, 6.2, 6.3, 6.4)
   - Navigation (Requirements: 7.1, 7.2, 7.4)
   - Alerts (Requirements: 5.4) - Semantic variants with color and icon indicators
   ========================================================================== */

/* ==========================================================================
   Button Component
   
   Requirements:
   - 3.1: Single border-radius value (8px / --radius-md) for all variants
   - 3.2: Exactly 4 variants: primary, secondary, outline, ghost
   - 3.3: 44px minimum touch target (--touch-target)
   - 3.6: Icons inline with 8px spacing (--space-sm)
   ========================================================================== */

/* Base Button Styles */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm); /* 8px icon spacing - Requirement 3.6 */
  min-height: var(--touch-target); /* 44px - Requirement 3.3 */
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  line-height: var(--line-height-tight);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--radius-md); /* 8px - Requirement 3.1 */
  cursor: pointer;
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              color var(--transition-fast),
              box-shadow var(--transition-fast);
  user-select: none;
  white-space: nowrap;
}

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

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

/* ==========================================================================
   Button Variants - Requirement 3.2
   Exactly 4 variants: primary, secondary, outline, ghost
   ========================================================================== */

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

.btn-primary:hover {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
}

.btn-primary:active {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

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

.btn-secondary:hover {
  background-color: var(--color-surface-hover);
  border-color: var(--color-border-hover);
}

.btn-secondary:active {
  background-color: var(--color-surface-active);
  border-color: var(--color-border-hover);
}

/* Outline Button - Transparent with border */
.btn-outline {
  background-color: transparent;
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.btn-outline:hover {
  background-color: var(--color-accent);
  color: var(--color-text-primary);
  border-color: var(--color-accent);
}

.btn-outline:active {
  background-color: var(--color-accent-hover);
  color: var(--color-text-primary);
  border-color: var(--color-accent-hover);
}

/* Ghost Button - Transparent, no border */
.btn-ghost {
  background-color: transparent;
  color: var(--color-text-secondary);
  border-color: transparent;
}

.btn-ghost:hover {
  background-color: var(--color-surface);
  color: var(--color-text-primary);
}

.btn-ghost:active {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

/* ==========================================================================
   Button Sizes
   ========================================================================== */

/* Small Button */
.btn-sm {
  min-height: 2rem; /* 32px */
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-sm);
}

/* Large Button */
.btn-lg {
  min-height: 3rem; /* 48px */
  padding: var(--space-sm) var(--space-lg);
  font-size: var(--font-size-lg);
}

/* ==========================================================================
   Button States
   ========================================================================== */

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

.btn.is-loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 1rem;
  height: 1rem;
  margin: -0.5rem 0 0 -0.5rem;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: btn-spinner 0.6s linear infinite;
}

/* Restore color for spinner visibility */
.btn-primary.is-loading::after {
  border-color: var(--color-text-primary);
  border-right-color: transparent;
}

.btn-secondary.is-loading::after {
  border-color: var(--color-text-primary);
  border-right-color: transparent;
}

.btn-outline.is-loading::after {
  border-color: var(--color-accent);
  border-right-color: transparent;
}

.btn-ghost.is-loading::after {
  border-color: var(--color-text-secondary);
  border-right-color: transparent;
}

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

/* ==========================================================================
   Button with Icon
   ========================================================================== */

/* Icon inside button inherits color */
.btn .icon {
  width: 1.25em;
  height: 1.25em;
  flex-shrink: 0;
}

.btn .icon svg {
  fill: currentColor;
  width: 100%;
  height: 100%;
}

/* Icon-only button */
.btn-icon {
  padding: var(--space-sm);
  min-width: var(--touch-target);
}

.btn-icon.btn-sm {
  padding: var(--space-xs);
  min-width: 2rem;
}

.btn-icon.btn-lg {
  padding: var(--space-sm);
  min-width: 3rem;
}

/* ==========================================================================
   Button Group
   ========================================================================== */

.btn-group {
  display: inline-flex;
}

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

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

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

.btn-group .btn:not(:last-child) {
  border-right-width: 0;
}

/* ==========================================================================
   Full Width Button
   ========================================================================== */

.btn-block {
  display: flex;
  width: 100%;
}

/* ==========================================================================
   Icon Component
   
   Requirements:
   - 4.1: Inline SVG with consistent structural pattern
   - 4.2: No CSS filters for color manipulation
   - 4.3: Exactly 4 sizes: sm (16px), base (20px), lg (24px), xl (32px)
   - 4.5: Icons inherit color from parent element via currentColor
   
   Usage Pattern (Inline SVG):
   <span class="icon">
     <svg viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
       <path d="..."/>
     </svg>
   </span>
   
   Or with size modifier:
   <span class="icon icon-lg">
     <svg viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
       <path d="..."/>
     </svg>
   </span>
   ========================================================================== */

/* Base Icon Styles */
.icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  width: 1.25rem;  /* 20px - base size */
  height: 1.25rem;
  color: currentColor; /* Inherit color from parent - Requirement 4.5 */
  vertical-align: middle;
}

/* Icon loaded via img tag - for external SVG files */
img.icon,
img.icon-base {
  display: inline-block;
  width: 1.25rem;  /* 20px - base size */
  height: 1.25rem;
  vertical-align: middle;
  flex-shrink: 0;
}

img.icon-sm,
img.icon-base.icon-sm {
  width: 1rem;
  height: 1rem;
}

img.icon-lg,
img.icon-base.icon-lg {
  width: 1.5rem;
  height: 1.5rem;
}

img.icon-xl,
img.icon-base.icon-xl {
  width: 2rem;
  height: 2rem;
}

/* SVG inside icon container - Requirement 4.1, 4.2, 4.5 */
.icon svg {
  width: 100%;
  height: 100%;
  fill: currentColor; /* Inherit color - Requirement 4.5 */
  /* NO filter property - Requirement 4.2 */
}

/* Ensure stroke-based SVGs also inherit color */
.icon svg path,
.icon svg circle,
.icon svg rect,
.icon svg line,
.icon svg polyline,
.icon svg polygon {
  fill: inherit;
  stroke: currentColor;
}

/* ==========================================================================
   Icon Sizes - Requirement 4.3
   Exactly 4 sizes: sm (16px), base (20px), lg (24px), xl (32px)
   ========================================================================== */

/* Small Icon - 16px */
.icon-sm {
  width: 1rem;
  height: 1rem;
}

/* Base Icon - 20px (default, no modifier needed) */
/* .icon already has 20px as default */

/* Large Icon - 24px */
.icon-lg {
  width: 1.5rem;
  height: 1.5rem;
}

/* Extra Large Icon - 32px */
.icon-xl {
  width: 2rem;
  height: 2rem;
}

/* ==========================================================================
   Icon Color Variants
   Icons inherit color by default, but explicit variants can be used
   ========================================================================== */

.icon-primary {
  color: var(--color-accent);
}

.icon-secondary {
  color: var(--color-text-secondary);
}

.icon-muted {
  color: var(--color-text-muted);
}

.icon-success {
  color: var(--color-success);
}

.icon-warning {
  color: var(--color-warning);
}

.icon-error {
  color: var(--color-error);
}

/* ==========================================================================
   Icon States
   ========================================================================== */

/* Loading/Spinning Icon */
.icon-spin {
  animation: icon-spin 1s linear infinite;
}

@keyframes icon-spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

/* Pulsing Icon */
.icon-pulse {
  animation: icon-pulse 2s ease-in-out infinite;
}

@keyframes icon-pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* ==========================================================================
   Icon in Context
   Icons automatically inherit color from their parent context
   ========================================================================== */

/* Icon in text - inline alignment */
.icon-inline {
  display: inline;
  width: 1em;
  height: 1em;
  vertical-align: -0.125em;
  margin-right: var(--space-xs);
}

/* Icon inline for img tags */
img.icon-inline {
  display: inline;
  width: 1em;
  height: 1em;
  vertical-align: -0.125em;
  margin-right: var(--space-xs);
}

/* Icon with text spacing */
.icon + span,
span + .icon {
  margin-left: var(--space-sm);
}

/* ==========================================================================
   Interactive Icon
   For standalone clickable icons
   ========================================================================== */

.icon-interactive {
  cursor: pointer;
  padding: var(--space-xs);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.icon-interactive:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.icon-interactive:active {
  background-color: var(--color-surface-active);
}

.icon-interactive:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* ==========================================================================
   Accessibility
   ========================================================================== */

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  .icon-spin,
  .icon-pulse {
    animation: none;
  }
}


/* ==========================================================================
   Form Component
   
   Requirements:
   - 5.1: Consistent border-radius (8px / --radius-md) for all input fields
   - 5.2: Clear focus states with visible outline
   - 5.4: Validation feedback inline with color and icon indicator
   - 5.5: 44px minimum height (--touch-target) for all interactive elements
   ========================================================================== */

/* ==========================================================================
   Form Group - Wrapper with consistent spacing
   ========================================================================== */

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
}

.form-group:last-child {
  margin-bottom: 0;
}

/* Inline form group for horizontal layouts */
.form-group-inline {
  flex-direction: row;
  align-items: center;
  gap: var(--space-sm);
}

/* ==========================================================================
   Form Label
   ========================================================================== */

.form-label {
  display: block;
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  line-height: var(--line-height-normal);
}

/* Required field indicator */
.form-label-required::after {
  content: ' *';
  color: var(--color-error);
}

/* Optional field indicator */
.form-label-optional::after {
  content: ' (optional)';
  font-weight: var(--font-weight-normal);
  color: var(--color-text-muted);
}

/* ==========================================================================
   Form Input, Select, Textarea - Base Styles
   
   Requirements:
   - 5.1: 8px border-radius (--radius-md)
   - 5.5: 44px min-height (--touch-target)
   ========================================================================== */

.form-input,
.form-select,
.form-textarea {
  display: block;
  width: 100%;
  min-height: var(--touch-target); /* 44px - Requirement 5.5 */
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md); /* 8px - Requirement 5.1 */
  transition: border-color var(--transition-fast),
              box-shadow var(--transition-fast),
              background-color var(--transition-fast);
}

/* Placeholder styling */
.form-input::placeholder,
.form-select::placeholder,
.form-textarea::placeholder {
  color: var(--color-text-muted);
  opacity: 1;
}

/* ==========================================================================
   Focus States - Requirement 5.2
   Clear focus states with visible outline
   ========================================================================== */

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: var(--focus-ring);
  background-color: var(--color-bg-elevated);
}

.form-input:focus-visible,
.form-select:focus-visible,
.form-textarea:focus-visible {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: var(--focus-ring);
}

/* ==========================================================================
   Hover States
   ========================================================================== */

.form-input:hover:not(:focus):not(:disabled),
.form-select:hover:not(:focus):not(:disabled),
.form-textarea:hover:not(:focus):not(:disabled) {
  border-color: var(--color-border-hover);
  background-color: var(--color-surface-hover);
}

/* ==========================================================================
   Disabled States
   ========================================================================== */

.form-input:disabled,
.form-select:disabled,
.form-textarea:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background-color: var(--color-bg-secondary);
}

/* ==========================================================================
   Error States - Requirement 5.4
   Indicate error with both color and icon
   ========================================================================== */

.form-input.is-error,
.form-select.is-error,
.form-textarea.is-error {
  border-color: var(--color-error);
  background-color: var(--color-surface);
}

.form-input.is-error:focus,
.form-select.is-error:focus,
.form-textarea.is-error:focus {
  border-color: var(--color-error);
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.3);
}

/* Success State */
.form-input.is-success,
.form-select.is-success,
.form-textarea.is-success {
  border-color: var(--color-success);
}

.form-input.is-success:focus,
.form-select.is-success:focus,
.form-textarea.is-success:focus {
  border-color: var(--color-success);
  box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.3);
}

/* ==========================================================================
   Select Specific Styles
   ========================================================================== */

.form-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%23a3a3a3' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-sm) center;
  background-size: 1rem;
  padding-right: var(--space-xl);
  cursor: pointer;
}

.form-select:focus {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%233b82f6' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
}

/* ==========================================================================
   Textarea Specific Styles
   ========================================================================== */

.form-textarea {
  min-height: calc(var(--touch-target) * 2); /* At least 2 lines */
  resize: vertical;
}

.form-textarea-sm {
  min-height: var(--touch-target);
}

.form-textarea-lg {
  min-height: calc(var(--touch-target) * 4);
}

/* ==========================================================================
   Input with Icon
   ========================================================================== */

.form-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.form-input-wrapper .form-input {
  padding-left: calc(var(--space-md) + 1.5rem);
}

.form-input-wrapper .icon {
  position: absolute;
  left: var(--space-sm);
  color: var(--color-text-muted);
  pointer-events: none;
}

/* Icon on right side */
.form-input-wrapper-right .form-input {
  padding-left: var(--space-md);
  padding-right: calc(var(--space-md) + 1.5rem);
}

.form-input-wrapper-right .icon {
  left: auto;
  right: var(--space-sm);
}

/* Clickable icon (e.g., password toggle) */
.form-input-wrapper .icon-interactive {
  pointer-events: auto;
  cursor: pointer;
}

/* ==========================================================================
   Form Error Message - Requirement 5.4
   Validation feedback inline with color and icon
   ========================================================================== */

.form-error {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--font-size-sm);
  color: var(--color-error);
  line-height: var(--line-height-normal);
}

.form-error .icon {
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

/* ==========================================================================
   Form Hint / Helper Text
   ========================================================================== */

.form-hint {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: var(--line-height-normal);
}

/* ==========================================================================
   Checkbox and Radio - Requirement 5.5
   Proper touch targets (44px minimum)
   ========================================================================== */

.form-check {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target); /* 44px - Requirement 5.5 */
  cursor: pointer;
}

.form-check-input {
  /* Hide native checkbox/radio */
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.form-check-box {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
  background-color: var(--color-surface);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              box-shadow var(--transition-fast);
}

/* Radio button is circular */
.form-check-radio .form-check-box {
  border-radius: 50%;
}

/* Checkbox/Radio hover state */
.form-check:hover .form-check-box {
  border-color: var(--color-border-hover);
  background-color: var(--color-surface-hover);
}

/* Checkbox/Radio focus state */
.form-check-input:focus-visible + .form-check-box {
  border-color: var(--color-accent);
  box-shadow: var(--focus-ring);
}

/* Checkbox/Radio checked state */
.form-check-input:checked + .form-check-box {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
}

/* Checkmark icon for checkbox */
.form-check-input:checked + .form-check-box::after {
  content: '';
  display: block;
  width: 0.5rem;
  height: 0.75rem;
  border: solid var(--color-text-primary);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg) translateY(-1px);
}

/* Dot for radio */
.form-check-radio .form-check-input:checked + .form-check-box::after {
  content: '';
  display: block;
  width: 0.5rem;
  height: 0.5rem;
  background-color: var(--color-text-primary);
  border: none;
  border-radius: 50%;
  transform: none;
}

/* Checkbox/Radio disabled state */
.form-check-input:disabled + .form-check-box {
  opacity: 0.5;
  cursor: not-allowed;
}

.form-check-input:disabled ~ .form-check-label {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Checkbox/Radio label */
.form-check-label {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
  line-height: var(--line-height-normal);
  cursor: pointer;
  user-select: none;
}

/* Error state for checkbox/radio */
.form-check.is-error .form-check-box {
  border-color: var(--color-error);
}

/* ==========================================================================
   Toggle Switch
   ========================================================================== */

.form-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target);
  cursor: pointer;
}

.form-toggle-input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.form-toggle-track {
  position: relative;
  width: 2.75rem;
  height: 1.5rem;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 0.75rem;
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast);
}

.form-toggle-thumb {
  position: absolute;
  top: 2px;
  left: 2px;
  width: calc(1.5rem - 6px);
  height: calc(1.5rem - 6px);
  background-color: var(--color-text-secondary);
  border-radius: 50%;
  transition: transform var(--transition-fast),
              background-color var(--transition-fast);
}

/* Toggle hover */
.form-toggle:hover .form-toggle-track {
  border-color: var(--color-border-hover);
}

/* Toggle focus */
.form-toggle-input:focus-visible + .form-toggle-track {
  border-color: var(--color-accent);
  box-shadow: var(--focus-ring);
}

/* Toggle checked */
.form-toggle-input:checked + .form-toggle-track {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
}

.form-toggle-input:checked + .form-toggle-track .form-toggle-thumb {
  transform: translateX(1.25rem);
  background-color: var(--color-text-primary);
}

/* Toggle disabled */
.form-toggle-input:disabled + .form-toggle-track {
  opacity: 0.5;
  cursor: not-allowed;
}

.form-toggle-label {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
  line-height: var(--line-height-normal);
  cursor: pointer;
}

/* ==========================================================================
   Form Actions - Button container
   ========================================================================== */

.form-actions {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

.form-actions-right {
  justify-content: flex-end;
}

.form-actions-center {
  justify-content: center;
}

.form-actions-between {
  justify-content: space-between;
}

/* Stack buttons on mobile */
@media (max-width: 640px) {
  .form-actions-stack {
    flex-direction: column;
  }
  
  .form-actions-stack .btn {
    width: 100%;
  }
}

/* ==========================================================================
   Input Sizes
   ========================================================================== */

.form-input-sm,
.form-select-sm {
  min-height: 2rem;
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-sm);
}

.form-input-lg,
.form-select-lg {
  min-height: 3rem;
  padding: var(--space-sm) var(--space-lg);
  font-size: var(--font-size-lg);
}

/* ==========================================================================
   Fieldset and Legend
   ========================================================================== */

.form-fieldset {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin: 0 0 var(--space-md) 0;
}

.form-legend {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  padding: 0 var(--space-sm);
}

/* ==========================================================================
   Inline Form
   ========================================================================== */

.form-inline {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: var(--space-sm);
}

.form-inline .form-group {
  margin-bottom: 0;
  flex: 1;
  min-width: 200px;
}

.form-inline .btn {
  flex-shrink: 0;
}

/* ==========================================================================
   Accessibility - Reduced Motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  .form-input,
  .form-select,
  .form-textarea,
  .form-check-box,
  .form-toggle-track,
  .form-toggle-thumb {
    transition: none;
  }
}


/* ==========================================================================
   Card Component
   
   Requirements:
   - 6.1: Single border-radius value (16px / --radius-lg) for all card variants
   - 6.2: Exactly 3 elevation levels: flat, raised, elevated
   - 6.3: Consistent padding (16px mobile, 24px desktop)
   - 6.4: Interactive card variant with subtle hover effects
   ========================================================================== */

/* ==========================================================================
   Base Card Styles
   ========================================================================== */

.card {
  display: block;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); /* 16px - Requirement 6.1 */
  padding: var(--space-md); /* 16px mobile default - Requirement 6.3 */
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              box-shadow var(--transition-base),
              transform var(--transition-fast);
}

/* Desktop padding - Requirement 6.3 */
@media (min-width: 768px) {
  .card {
    padding: var(--space-lg); /* 24px desktop - Requirement 6.3 */
  }
}

/* ==========================================================================
   Card Elevations - Requirement 6.2
   Exactly 3 elevation levels: flat (default), raised, elevated
   ========================================================================== */

/* Flat Card (default) - No shadow */
/* .card already has flat styling as default */

/* Raised Card - Subtle shadow */
.card-raised {
  box-shadow: var(--shadow-sm);
}

/* Elevated Card - Prominent shadow */
.card-elevated {
  box-shadow: var(--shadow-md);
}

/* ==========================================================================
   Interactive Card - Requirement 6.4
   Indicates interactivity through subtle hover effects
   ========================================================================== */

.card-interactive {
  cursor: pointer;
}

.card-interactive:hover {
  border-color: var(--color-border-hover);
  background-color: var(--color-surface-hover);
}

.card-interactive:active {
  background-color: var(--color-surface-active);
}

/* Interactive card with elevation change on hover */
.card-interactive.card-raised:hover {
  box-shadow: var(--shadow-md);
}

.card-interactive.card-elevated:hover {
  box-shadow: var(--shadow-lg);
}

/* Focus state for keyboard navigation */
.card-interactive:focus-visible {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: var(--focus-ring);
}

/* ==========================================================================
   Card Header
   ========================================================================== */

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
}

.card-header:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.card-title {
  font-family: var(--font-family);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  line-height: var(--line-height-tight);
  margin: 0;
}

.card-subtitle {
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-normal);
  color: var(--color-text-secondary);
  line-height: var(--line-height-normal);
  margin: var(--space-xs) 0 0 0;
}

/* ==========================================================================
   Card Body
   ========================================================================== */

.card-body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
  line-height: var(--line-height-normal);
}

.card-body > *:last-child {
  margin-bottom: 0;
}

/* ==========================================================================
   Card Footer
   ========================================================================== */

.card-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-sm);
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

.card-footer:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
}

/* Footer alignment variants */
.card-footer-left {
  justify-content: flex-start;
}

.card-footer-center {
  justify-content: center;
}

.card-footer-between {
  justify-content: space-between;
}

/* ==========================================================================
   Card Image
   ========================================================================== */

.card-image {
  margin: calc(-1 * var(--space-md));
  margin-bottom: var(--space-md);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  overflow: hidden;
}

.card-image img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* Desktop image margin adjustment */
@media (min-width: 768px) {
  .card-image {
    margin: calc(-1 * var(--space-lg));
    margin-bottom: var(--space-lg);
  }
}

/* Image at bottom of card */
.card-image-bottom {
  margin-top: var(--space-md);
  margin-bottom: calc(-1 * var(--space-md));
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
}

@media (min-width: 768px) {
  .card-image-bottom {
    margin-top: var(--space-lg);
    margin-bottom: calc(-1 * var(--space-lg));
  }
}

/* ==========================================================================
   Card Variants
   ========================================================================== */

/* Accent border card */
.card-accent {
  border-left: 3px solid var(--color-accent);
}

/* Success card */
.card-success {
  border-left: 3px solid var(--color-success);
}

/* Warning card */
.card-warning {
  border-left: 3px solid var(--color-warning);
}

/* Error card */
.card-error {
  border-left: 3px solid var(--color-error);
}

/* ==========================================================================
   Card Grid Layout
   ========================================================================== */

.card-grid {
  display: grid;
  gap: var(--space-md);
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ==========================================================================
   Card Stack Layout
   ========================================================================== */

.card-stack {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

/* ==========================================================================
   Compact Card
   ========================================================================== */

.card-compact {
  padding: var(--space-sm);
}

@media (min-width: 768px) {
  .card-compact {
    padding: var(--space-md);
  }
}

.card-compact .card-header {
  margin-bottom: var(--space-sm);
  padding-bottom: var(--space-sm);
}

.card-compact .card-footer {
  margin-top: var(--space-sm);
  padding-top: var(--space-sm);
}

/* ==========================================================================
   Full Width Card (no border-radius)
   ========================================================================== */

.card-full {
  border-radius: 0;
  border-left: none;
  border-right: none;
}

/* ==========================================================================
   Card with Icon
   ========================================================================== */

.card-icon {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
}

.card-icon .icon {
  flex-shrink: 0;
  color: var(--color-accent);
}

.card-icon-content {
  flex: 1;
  min-width: 0;
}

/* ==========================================================================
   Accessibility - Reduced Motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  .card,
  .card-interactive {
    transition: none;
  }
}


/* ==========================================================================
   Navigation Component
   
   Requirements:
   - 7.1: Maximum 6 primary navigation items
   - 7.2: Mobile menu that is easy to open and close
   - 7.4: Indicate the current page clearly
   
   Structure:
   <nav class="navbar">
     <div class="navbar-brand">
       <a href="/" class="navbar-logo">Brand</a>
       <button class="navbar-toggle" aria-label="Toggle menu">
         <span class="icon">...</span>
       </button>
     </div>
     <div class="navbar-menu">
       <ul class="nav-list">
         <li class="nav-item">
           <a href="/" class="nav-link is-active">Home</a>
         </li>
         <li class="nav-item nav-dropdown">
           <button class="nav-link nav-dropdown-toggle">
             Dropdown <span class="icon">...</span>
           </button>
           <ul class="nav-dropdown-menu">
             <li><a href="#" class="nav-dropdown-item">Item 1</a></li>
           </ul>
         </li>
       </ul>
     </div>
   </nav>
   ========================================================================== */

/* ==========================================================================
   Navbar - Main Container
   ========================================================================== */

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--touch-target); /* 44px minimum */
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-border);
}

/* Fixed navbar variant */
.navbar-fixed {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
}

/* Sticky navbar variant */
.navbar-sticky {
  position: sticky;
  top: 0;
  z-index: 1000;
}

/* ==========================================================================
   Navbar Brand
   ========================================================================== */

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.navbar-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-family);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.navbar-logo:hover {
  color: var(--color-accent);
}

.navbar-logo .icon {
  width: 1.5rem;
  height: 1.5rem;
}

/* ==========================================================================
   Navbar Toggle - Mobile Menu Button (Requirement 7.2)
   ========================================================================== */

.navbar-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: var(--touch-target); /* 44px touch target */
  min-height: var(--touch-target);
  padding: var(--space-sm);
  background-color: transparent;
  border: none;
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  cursor: pointer;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.navbar-toggle:hover {
  background-color: var(--color-surface-hover);
}

.navbar-toggle:active {
  background-color: var(--color-surface-active);
}

.navbar-toggle:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* Hamburger icon lines */
.navbar-toggle .icon {
  width: 1.5rem;
  height: 1.5rem;
}

/* Hamburger icon using span elements */
.navbar-toggle span {
  display: block;
  width: 1.25rem;
  height: 2px;
  background-color: currentColor;
  border-radius: 1px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.navbar-toggle span + span {
  margin-top: 5px;
}

/* Hamburger to X animation when active */
.navbar-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.navbar-toggle.active span:nth-child(2) {
  opacity: 0;
}

.navbar-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Hide toggle on desktop */
@media (min-width: 768px) {
  .navbar-toggle {
    display: none;
  }
}

/* ==========================================================================
   Navbar Menu - Container for Nav Items
   ========================================================================== */

.navbar-menu {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 999;
  background-color: var(--color-bg-primary);
  padding: var(--space-lg);
  overflow-y: auto;
  /* Slide-in animation - Requirement 7.2 */
  transform: translateX(-100%);
  transition: transform var(--transition-base);
}

/* Mobile menu open state */
.navbar-menu.is-open,
.navbar-nav.show {
  display: block;
  transform: translateX(0);
}

/* ==========================================================================
   Navbar Nav - Alias for navbar-menu (for template compatibility)
   ========================================================================== */

.navbar-nav {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 999;
  background-color: var(--color-bg-primary);
  padding: var(--space-lg);
  overflow-y: auto;
  transform: translateX(-100%);
  transition: transform var(--transition-base);
}

/* Desktop: show menu inline */
@media (min-width: 768px) {
  .navbar-menu,
  .navbar-nav {
    display: flex;
    position: static;
    background-color: transparent;
    padding: 0;
    overflow: visible;
    transform: none;
    transition: none;
  }
  
  .navbar-menu.is-open,
  .navbar-nav.show {
    transform: none;
  }
}

/* Mobile menu header with close button */
.navbar-menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
}

@media (min-width: 768px) {
  .navbar-menu-header {
    display: none;
  }
}

/* Close button in mobile menu */
.navbar-close {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  padding: var(--space-sm);
  background-color: transparent;
  border: none;
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.navbar-close:hover {
  background-color: var(--color-surface-hover);
}

.navbar-close:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* ==========================================================================
   Nav List - Navigation Items Container
   ========================================================================== */

.nav-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  list-style: none;
  margin: 0;
  padding: 0;
}

/* Desktop: horizontal layout */
@media (min-width: 768px) {
  .nav-list {
    flex-direction: row;
    align-items: center;
    gap: var(--space-sm);
  }
}

/* ==========================================================================
   Nav Item
   ========================================================================== */

.nav-item {
  position: relative;
}

/* ==========================================================================
   Nav Link - Requirement 7.4 (Active State Indication)
   ========================================================================== */

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target); /* 44px touch target */
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  background-color: transparent;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
  width: 100%;
}

/* Hover state */
.nav-link:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

/* Active/pressed state */
.nav-link:active {
  background-color: var(--color-surface-active);
}

/* Focus state for accessibility */
.nav-link:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* ==========================================================================
   Active State - Requirement 7.4
   Clearly indicate the current page
   ========================================================================== */

.nav-link.is-active,
.nav-link[aria-current="page"] {
  color: var(--color-accent);
  background-color: var(--color-surface);
  font-weight: var(--font-weight-semibold);
}

.nav-link.is-active:hover,
.nav-link[aria-current="page"]:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-accent);
}

/* Active indicator bar (desktop only) */
@media (min-width: 768px) {
  .nav-link.is-active::after,
  .nav-link[aria-current="page"]::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: var(--space-sm);
    right: var(--space-sm);
    height: 2px;
    background-color: var(--color-accent);
    border-radius: 1px;
  }
}

/* ==========================================================================
   Nav Link with Icon
   ========================================================================== */

.nav-link .icon {
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
}

/* Icon-only nav link */
.nav-link-icon {
  padding: var(--space-sm);
  min-width: var(--touch-target);
  justify-content: center;
}

/* ==========================================================================
   Dropdown Menu - Requirement 7.2
   ========================================================================== */

.nav-dropdown {
  position: relative;
}

.nav-dropdown-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

/* Dropdown arrow icon */
.nav-dropdown-toggle .icon-chevron {
  width: 1rem;
  height: 1rem;
  transition: transform var(--transition-fast);
}

/* Rotate arrow when open */
.nav-dropdown.is-open .nav-dropdown-toggle .icon-chevron {
  transform: rotate(180deg);
}

/* Dropdown menu container */
.nav-dropdown-menu {
  display: none;
  list-style: none;
  margin: 0;
  padding: var(--space-xs) 0;
  background-color: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
  min-width: 12rem;
  z-index: 1001;
}

/* Mobile: dropdown inline */
.nav-dropdown-menu {
  margin-top: var(--space-xs);
  margin-left: var(--space-md);
  background-color: transparent;
  border: none;
  box-shadow: none;
  border-left: 2px solid var(--color-border);
  border-radius: 0;
  padding-left: var(--space-sm);
}

/* Desktop: dropdown absolute positioned */
@media (min-width: 768px) {
  .nav-dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    margin: var(--space-xs) 0 0 0;
    background-color: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    padding: var(--space-xs) 0;
  }
  
  /* Right-aligned dropdown */
  .nav-dropdown-right .nav-dropdown-menu {
    left: auto;
    right: 0;
  }
}

/* Show dropdown when open */
.nav-dropdown.is-open .nav-dropdown-menu {
  display: block;
}

/* Dropdown item */
.nav-dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.nav-dropdown-item:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.nav-dropdown-item:focus-visible {
  outline: none;
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.nav-dropdown-item.is-active,
.nav-dropdown-item[aria-current="page"] {
  color: var(--color-accent);
  background-color: var(--color-surface);
}

/* Dropdown divider */
.nav-dropdown-divider {
  height: 1px;
  margin: var(--space-xs) 0;
  background-color: var(--color-border);
}

/* Dropdown header */
.nav-dropdown-header {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ==========================================================================
   Dropdown Component - Alias classes for template compatibility
   ========================================================================== */

.dropdown {
  position: relative;
}

.dropdown-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.dropdown-menu {
  display: none;
  list-style: none;
  margin: 0;
  padding: var(--space-xs) 0;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  min-width: 12rem;
  z-index: var(--z-dropdown);
}

/* Mobile: dropdown inline */
.dropdown-menu {
  margin-top: var(--space-xs);
  margin-left: var(--space-md);
}

/* Desktop: dropdown absolute positioned */
@media (min-width: 768px) {
  .dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    margin-top: var(--space-xs);
    margin-left: 0;
    box-shadow: var(--shadow-md);
  }
  
  /* Right-aligned dropdown */
  .dropdown-right .dropdown-menu {
    left: auto;
    right: 0;
  }
}

/* Show dropdown when open */
.dropdown.show .dropdown-menu {
  display: block;
}

/* Dropdown item */
.dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-base);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.dropdown-item:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.dropdown-item:focus-visible {
  outline: none;
  background-color: var(--color-surface-hover);
}

/* Dropdown divider */
.dropdown-divider {
  height: 1px;
  margin: var(--space-xs) 0;
  background-color: var(--color-border);
}

/* ==========================================================================
   Mobile Menu Overlay
   ========================================================================== */

.navbar-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 998;
  opacity: 0;
  transition: opacity var(--transition-base);
}

.navbar-overlay.is-visible,
.navbar-overlay.show {
  display: block;
  opacity: 1;
}

@media (min-width: 768px) {
  .navbar-overlay {
    display: none !important;
  }
}

/* ==========================================================================
   Navbar Actions - Right-side items (user menu, etc.)
   ========================================================================== */

.navbar-actions {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-left: auto;
}

/* Hide on mobile, show in mobile menu instead */
.navbar-actions-desktop {
  display: none;
}

@media (min-width: 768px) {
  .navbar-actions-desktop {
    display: flex;
  }
}

/* ==========================================================================
   Navbar Variants
   ========================================================================== */

/* Transparent navbar (for hero sections) */
.navbar-transparent {
  background-color: transparent;
  border-bottom-color: transparent;
}

/* Compact navbar */
.navbar-compact {
  padding: var(--space-xs) var(--space-md);
}

/* Centered navbar */
.navbar-centered {
  justify-content: center;
}

.navbar-centered .navbar-brand {
  position: absolute;
  left: var(--space-md);
}

.navbar-centered .navbar-actions {
  position: absolute;
  right: var(--space-md);
}

/* ==========================================================================
   Breadcrumb Navigation
   ========================================================================== */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-xs);
  list-style: none;
  margin: 0;
  padding: var(--space-sm) 0;
  font-size: var(--font-size-sm);
}

.breadcrumb-item {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  color: var(--color-text-muted);
}

.breadcrumb-item a {
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.breadcrumb-item a:hover {
  color: var(--color-accent);
}

.breadcrumb-item a:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

/* Current page (last item) */
.breadcrumb-item:last-child {
  color: var(--color-text-primary);
  font-weight: var(--font-weight-medium);
}

/* Separator */
.breadcrumb-item:not(:last-child)::after {
  content: '/';
  margin-left: var(--space-xs);
  color: var(--color-text-muted);
}

/* ==========================================================================
   Tab Navigation
   ========================================================================== */

.nav-tabs {
  display: flex;
  gap: var(--space-xs);
  border-bottom: 1px solid var(--color-border);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.nav-tabs::-webkit-scrollbar {
  display: none;
}

.nav-tab {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  background-color: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  cursor: pointer;
  white-space: nowrap;
  transition: color var(--transition-fast),
              border-color var(--transition-fast);
}

.nav-tab:hover {
  color: var(--color-text-primary);
}

.nav-tab:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.nav-tab.is-active,
.nav-tab[aria-selected="true"] {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* ==========================================================================
   Pill Navigation
   ========================================================================== */

.nav-pills {
  display: flex;
  gap: var(--space-xs);
  padding: var(--space-xs);
  background-color: var(--color-surface);
  border-radius: var(--radius-md);
}

.nav-pill {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  min-height: calc(var(--touch-target) - var(--space-sm));
  padding: var(--space-xs) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  background-color: transparent;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.nav-pill:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.nav-pill:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.nav-pill.is-active,
.nav-pill[aria-selected="true"] {
  background-color: var(--color-accent);
  color: var(--color-text-primary);
}

/* ==========================================================================
   Sidebar Navigation
   ========================================================================== */

.nav-sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.nav-sidebar-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  min-height: var(--touch-target);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text-secondary);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.nav-sidebar-item:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.nav-sidebar-item:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.nav-sidebar-item.is-active,
.nav-sidebar-item[aria-current="page"] {
  background-color: var(--color-surface);
  color: var(--color-accent);
  font-weight: var(--font-weight-medium);
}

.nav-sidebar-item .icon {
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
}

/* Sidebar section header */
.nav-sidebar-header {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Sidebar divider */
.nav-sidebar-divider {
  height: 1px;
  margin: var(--space-sm) 0;
  background-color: var(--color-border);
}

/* ==========================================================================
   Accessibility - Reduced Motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  .navbar-menu,
  .navbar-overlay,
  .nav-link,
  .nav-dropdown-toggle .icon-chevron,
  .nav-dropdown-item,
  .nav-tab,
  .nav-pill,
  .nav-sidebar-item {
    transition: none;
  }
}


/* ==========================================================================
   Alert Component
   
   Requirements:
   - 5.4: Validation feedback inline with color and icon indicator
   
   Structure:
   <div class="alert alert-success">
     <span class="icon alert-icon">...</span>
     <div class="alert-content">
       <p class="alert-message">Success message here</p>
     </div>
     <button class="alert-dismiss" aria-label="Dismiss">
       <span class="icon">...</span>
     </button>
   </div>
   ========================================================================== */

/* ==========================================================================
   Base Alert Styles
   ========================================================================== */

.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  padding: var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  border-left-width: 3px;
}

/* Alert icon - Requirement 5.4 (color and icon indicator) */
.alert-icon {
  flex-shrink: 0;
  width: 1.25rem;
  height: 1.25rem;
  margin-top: 0.125rem; /* Align with first line of text */
}

.alert-icon svg {
  fill: currentColor;
  width: 100%;
  height: 100%;
}

/* Alert content container */
.alert-content {
  flex: 1;
  min-width: 0;
}

/* Alert message text */
.alert-message {
  margin: 0;
  color: var(--color-text-primary);
}

/* Alert title (optional) */
.alert-title {
  margin: 0 0 var(--space-xs) 0;
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
}

/* Alert description (optional, for longer content) */
.alert-description {
  margin: var(--space-xs) 0 0 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

/* ==========================================================================
   Alert Semantic Variants - Requirement 5.4
   Success, Warning, Error, Info with color and icon indicator
   ========================================================================== */

/* Success Alert */
.alert-success {
  background-color: rgba(34, 197, 94, 0.1);
  border-color: var(--color-success);
  border-left-color: var(--color-success);
}

.alert-success .alert-icon {
  color: var(--color-success);
}

.alert-success .alert-title {
  color: var(--color-success);
}

/* Warning Alert */
.alert-warning {
  background-color: rgba(234, 179, 8, 0.1);
  border-color: var(--color-warning);
  border-left-color: var(--color-warning);
}

.alert-warning .alert-icon {
  color: var(--color-warning);
}

.alert-warning .alert-title {
  color: var(--color-warning);
}

/* Error Alert */
.alert-error {
  background-color: rgba(239, 68, 68, 0.1);
  border-color: var(--color-error);
  border-left-color: var(--color-error);
}

.alert-error .alert-icon {
  color: var(--color-error);
}

.alert-error .alert-title {
  color: var(--color-error);
}

/* Info Alert */
.alert-info {
  background-color: rgba(59, 130, 246, 0.1);
  border-color: var(--color-accent);
  border-left-color: var(--color-accent);
}

.alert-info .alert-icon {
  color: var(--color-accent);
}

.alert-info .alert-title {
  color: var(--color-accent);
}

/* ==========================================================================
   Dismissible Alert
   ========================================================================== */

.alert-dismissible {
  padding-right: var(--space-xl);
  position: relative;
}

.alert-dismiss {
  position: absolute;
  top: var(--space-sm);
  right: var(--space-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.75rem;
  height: 1.75rem;
  padding: 0;
  background-color: transparent;
  border: none;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

/* Alert close button - alias for alert-dismiss */
.alert-close {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  padding: var(--space-xs);
  margin-left: auto;
  background-color: transparent;
  border: none;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: background-color var(--transition-fast),
              color var(--transition-fast);
}

.alert-close:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.alert-close:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.alert-dismiss:hover {
  background-color: var(--color-surface-hover);
  color: var(--color-text-primary);
}

.alert-dismiss:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.alert-dismiss .icon {
  width: 1rem;
  height: 1rem;
}

/* ==========================================================================
   Alert Variants
   ========================================================================== */

/* Compact alert (less padding) */
.alert-compact {
  padding: var(--space-sm);
}

/* Inline alert (no background, minimal styling) */
.alert-inline {
  padding: 0;
  background-color: transparent;
  border: none;
  border-radius: 0;
}

/* Full-width alert (no border-radius) */
.alert-full {
  border-radius: 0;
  border-left-width: 1px;
  border-right: none;
  border-left: none;
}

/* ==========================================================================
   Alert with Actions
   ========================================================================== */

.alert-actions {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
}

.alert-actions .btn {
  font-size: var(--font-size-sm);
}

/* ==========================================================================
   Alert List (for multiple alerts)
   ========================================================================== */

.alert-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

/* ==========================================================================
   Toast Alert (positioned fixed)
   ========================================================================== */

.alert-toast {
  position: fixed;
  bottom: var(--space-lg);
  right: var(--space-lg);
  max-width: 24rem;
  box-shadow: var(--shadow-lg);
  z-index: 1100;
  animation: alert-slide-in var(--transition-base) ease-out;
}

/* Toast container for multiple toasts */
.toast-container {
  position: fixed;
  bottom: var(--space-lg);
  right: var(--space-lg);
  display: flex;
  flex-direction: column-reverse;
  gap: var(--space-sm);
  z-index: 1100;
  max-width: 24rem;
}

/* Toast slide-in animation */
@keyframes alert-slide-in {
  from {
    opacity: 0;
    transform: translateX(100%);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* Toast slide-out animation (for JS removal) */
.alert-toast.is-leaving {
  animation: alert-slide-out var(--transition-base) ease-in forwards;
}

@keyframes alert-slide-out {
  from {
    opacity: 1;
    transform: translateX(0);
  }
  to {
    opacity: 0;
    transform: translateX(100%);
  }
}

/* ==========================================================================
   Accessibility - Reduced Motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  .alert-dismiss,
  .alert-toast {
    transition: none;
    animation: none;
  }
  
  .alert-toast.is-leaving {
    animation: none;
    opacity: 0;
  }
}

/* ==========================================================================
   Footer Component
   ========================================================================== */

.footer {
  margin-top: auto;
  padding: var(--space-lg) 0;
  background-color: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

@media (min-width: 768px) {
  .footer-content {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer-title {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
}

.footer-description {
  margin: 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.footer-nav {
  display: flex;
  gap: var(--space-md);
}

.footer-link {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--color-accent);
}

.footer-link:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

/* ==========================================================================
   Main Content Area
   ========================================================================== */

.main-content {
  flex: 1;
  padding: var(--space-lg) 0;
}

/* ==========================================================================
   Skip Link - Accessibility
   ========================================================================== */

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  z-index: var(--z-tooltip);
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-accent);
  color: var(--color-text-primary);
  border-radius: var(--radius-md);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
}

.skip-link:focus {
  top: var(--space-md);
}

/* Screen reader focusable */
.sr-only-focusable:focus,
.sr-only-focusable:active {
  position: static;
  width: auto;
  height: auto;
  padding: inherit;
  margin: inherit;
  overflow: visible;
  clip: auto;
  white-space: normal;
}

/* ==========================================================================
   Flash Messages Container
   ========================================================================== */

.flash-messages {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}


/* ==========================================================================
   Auth Page Components
   
   Simplified auth-specific styles that work with the unified design system.
   ========================================================================== */

/* Auth Container - Centers the auth card */
.auth-container {
  min-height: calc(100vh - 200px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg) var(--space-md);
}

/* Auth Card - Constrained width card for auth forms */
.auth-card {
  width: 100%;
  max-width: 28rem; /* 448px */
}

/* Auth Divider - Separator with text */
.auth-divider {
  display: flex;
  align-items: center;
  text-align: center;
  margin: var(--space-lg) 0;
}

.auth-divider::before,
.auth-divider::after {
  content: '';
  flex: 1;
  border-bottom: 1px solid var(--color-border);
}

.auth-divider span {
  padding: 0 var(--space-md);
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

/* Auth Links - Links section below form */
.auth-links {
  margin-top: var(--space-md);
}

.auth-links p {
  margin: 0;
}

/* Password Strength Indicator */
.password-strength {
  margin-top: var(--space-sm);
}

.password-strength-bar {
  height: 4px;
  background-color: var(--color-surface);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.password-strength-fill {
  height: 100%;
  transition: width var(--transition-fast), background-color var(--transition-fast);
  border-radius: var(--radius-sm);
}

.password-strength-fill.weak {
  background-color: var(--color-error);
}

.password-strength-fill.fair {
  background-color: var(--color-warning);
}

.password-strength-fill.good {
  background-color: var(--color-accent);
}

.password-strength-fill.strong {
  background-color: var(--color-success);
}

.password-strength-text {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
}

/* Responsive adjustments for auth */
@media (max-width: 640px) {
  .auth-container {
    padding: var(--space-md);
  }
  
  .auth-card {
    max-width: 100%;
  }
}