/* Navigation Accessibility & Focus States */

/* ==========================================
   Skip Link (WCAG 2.1 AA Requirement)
   ========================================== */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  z-index: 9999;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  text-decoration: none;
  border-radius: var(--radius-md);
  font-weight: 500;
  transition: top 0.2s;
}

.skip-link:focus {
  top: var(--space-md);
  outline: var(--focus-ring-width) solid var(--color-text-inverse);
  outline-offset: var(--focus-ring-offset);
}

/* ==========================================
   Sidebar Navigation Structure
   ========================================== */
.sidebar {
  background: var(--color-sidebar);
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  color: var(--color-text-inverse);
  padding: var(--space-md) var(--space-lg);
  font-size: var(--font-size-xl);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar-section {
  color: rgba(255, 255, 255, 0.5);
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: var(--space-lg) var(--space-lg) var(--space-sm);
  margin-top: var(--space-sm);
}

/* ==========================================
   Navigation Links with Accessibility
   ========================================== */
.sidebar .nav-link {
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-sm) var(--space-lg);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  transition: background 0.15s, color 0.15s;
  position: relative;
  border: none;
  border-radius: 0;
}

.sidebar .nav-link:hover {
  color: var(--color-text-inverse);
  background: rgba(255, 255, 255, 0.1);
}

.sidebar .nav-link.active {
  color: var(--color-text-inverse);
  background: var(--color-primary);
}

/* WCAG-compliant focus indicator (2px min, 3:1 contrast) */
.sidebar .nav-link:focus-visible {
  outline: none;
  box-shadow: inset 0 0 0 var(--focus-ring-width) var(--mc-sky);
  color: var(--color-text-inverse);
}

/* Ensure icon has consistent size and alignment */
.sidebar .nav-link i {
  width: 1.25rem;
  text-align: center;
  flex-shrink: 0;
}

/* ==========================================
   Active Link Visual Indicator
   ========================================== */
.sidebar .nav-link.active::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--mc-sky);
}

/* ==========================================
   Sidebar Footer
   ========================================== */
.sidebar-footer {
  margin-top: auto;
  padding: var(--space-md);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar-footer .btn:focus-visible {
  outline: var(--focus-ring-width) solid var(--mc-sky);
  outline-offset: var(--focus-ring-offset);
}

/* ==========================================
   Top Navbar Focus States
   ========================================== */
.top-navbar .btn:focus-visible,
.top-navbar .theme-toggle:focus-visible {
  outline: var(--focus-ring-width) solid var(--color-primary);
  outline-offset: var(--focus-ring-offset);
}

.top-navbar a:focus-visible {
  outline: var(--focus-ring-width) solid var(--color-primary);
  outline-offset: var(--focus-ring-offset);
}

.sidebar-toggle:focus-visible {
  outline: var(--focus-ring-width) solid var(--color-primary);
  outline-offset: var(--focus-ring-offset);
}

/* ==========================================
   Dropdown Menu Focus States
   ========================================== */
.dropdown-menu .dropdown-item:focus-visible {
  outline: none;
  background-color: var(--color-surface-2);
  box-shadow: inset var(--focus-ring-width) 0 0 0 var(--color-primary);
}

/* ==========================================
   Dark Mode Adjustments
   ========================================== */
[data-bs-theme="dark"] .skip-link {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

[data-bs-theme="dark"] .sidebar .nav-link:focus-visible {
  box-shadow: inset 0 0 0 var(--focus-ring-width) var(--mc-sky);
}

/* ==========================================
   High Contrast Mode Support
   ========================================== */
@media (prefers-contrast: high) {
  .sidebar .nav-link:focus-visible {
    outline: 3px solid currentColor;
    outline-offset: 2px;
  }

  .skip-link:focus {
    outline: 3px solid currentColor;
    outline-offset: 2px;
  }
}

/* ==========================================
   Reduced Motion Support
   ========================================== */
@media (prefers-reduced-motion: reduce) {
  .skip-link {
    transition: none;
  }

  .sidebar .nav-link {
    transition: none;
  }
}