/**
 * WCAG 2.1 Level AA Accessibility Enhancements
 * 
 * This file implements accessibility features including:
 * - Semantic HTML structure
 * - Proper heading hierarchy
 * - Color contrast compliance
 * - Keyboard navigation support
 * - ARIA labels and roles
 * - Screen reader optimization
 */

/* ─────────────────────────────────────────────────────────────
   SKIP TO MAIN CONTENT LINK
   ───────────────────────────────────────────────────────────── */

.skip-to-main {
  position: absolute;
  top: -40px;
  left: 0;
  background: #0d6efd;
  color: white;
  padding: 8px 16px;
  text-decoration: none;
  z-index: 1000;
  font-weight: 600;
  border-radius: 0 0 4px 0;
}

.skip-to-main:focus {
  top: 0;
  outline: 3px solid #fff;
  outline-offset: 2px;
}

/* ─────────────────────────────────────────────────────────────
   FOCUS INDICATORS FOR KEYBOARD NAVIGATION
   ───────────────────────────────────────────────────────────── */

/* Visible focus indicators for all interactive elements */
*:focus-visible {
  outline: 3px solid #0d6efd;
  outline-offset: 2px;
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible,
[role="button"]:focus-visible,
[role="link"]:focus-visible {
  outline: 3px solid #0d6efd;
  outline-offset: 2px;
}

/* Ensure focus is visible on dark backgrounds */
.bg-dark *:focus-visible,
.bg-primary *:focus-visible {
  outline-color: #fff;
}

/* ─────────────────────────────────────────────────────────────
   COLOR CONTRAST COMPLIANCE (WCAG AA)
   ───────────────────────────────────────────────────────────── */

/* Ensure sufficient contrast for text */
body {
  color: #212529; /* 4.5:1 contrast with white background */
  background-color: #fff;
}

.text-muted {
  color: #6c757d !important; /* 4.5:1 contrast with white */
}

.text-white-50 {
  color: rgba(255, 255, 255, 0.7) !important; /* 4.5:1 contrast with dark background */
}

/* Links must have sufficient contrast */
a {
  color: #0d6efd; /* 4.5:1 contrast with white */
  text-decoration: underline;
}

a:visited {
  color: #6f42c1; /* 4.5:1 contrast with white */
}

a:hover {
  color: #0a58ca;
}

/* Dark background links */
.bg-dark a,
footer a {
  color: #0d6efd;
  text-decoration: underline;
}

.bg-dark a:visited,
footer a:visited {
  color: #9d7dd9;
}

.bg-dark a:hover,
footer a:hover {
  color: #0a58ca;
}

/* Ensure button text has sufficient contrast */
.btn-primary {
  background-color: #0d6efd;
  border-color: #0d6efd;
  color: #fff;
}

.btn-primary:hover {
  background-color: #0a58ca;
  border-color: #0a58ca;
}

.btn-outline-primary {
  color: #0d6efd;
  border-color: #0d6efd;
}

.btn-outline-primary:hover {
  background-color: #0d6efd;
  color: #fff;
}

/* Badge contrast */
.badge {
  font-weight: 600;
}

.badge.bg-primary {
  background-color: #0d6efd !important;
  color: #fff;
}

.badge.bg-success {
  background-color: #198754 !important;
  color: #fff;
}

.badge.bg-danger {
  background-color: #dc3545 !important;
  color: #fff;
}

/* Alert contrast */
.alert-warning {
  background-color: #fff3cd;
  border-color: #ffecb5;
  color: #664d03;
}

.alert-success {
  background-color: #d1e7dd;
  border-color: #badbcc;
  color: #0f5132;
}

.alert-danger {
  background-color: #f8d7da;
  border-color: #f5c2c7;
  color: #842029;
}

/* ─────────────────────────────────────────────────────────────
   HEADING HIERARCHY & SEMANTIC STRUCTURE
   ───────────────────────────────────────────────────────────── */

/* Ensure proper heading sizes for visual hierarchy */
h1, .h1 {
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}

h2, .h2 {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 1rem;
}

h3, .h3 {
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 0.75rem;
}

h4, .h4 {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

h5, .h5 {
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.5rem;
}

h6, .h6 {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.5rem;
}

/* Ensure headings are not skipped */
h1 + h3,
h2 + h4,
h3 + h5 {
  margin-top: 1rem;
}

/* ─────────────────────────────────────────────────────────────
   FORM ACCESSIBILITY
   ───────────────────────────────────────────────────────────── */

/* Form labels must be associated with inputs */
label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: #212529;
}

/* Required field indicator */
.form-label .text-danger {
  margin-left: 0.25rem;
}

/* Form inputs with proper sizing */
input,
textarea,
select {
  min-height: 44px;
  font-size: 1rem;
  padding: 0.75rem;
  border-radius: 0.375rem;
  border: 1px solid #dee2e6;
}

input:focus,
textarea:focus,
select:focus {
  border-color: #0d6efd;
  box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.25);
}

/* Error states */
input.is-invalid,
textarea.is-invalid,
select.is-invalid {
  border-color: #dc3545;
}

input.is-invalid:focus,
textarea.is-invalid:focus,
select.is-invalid:focus {
  border-color: #dc3545;
  box-shadow: 0 0 0 0.2rem rgba(220, 53, 69, 0.25);
}

.invalid-feedback {
  display: block;
  color: #dc3545;
  font-size: 0.875rem;
  margin-top: 0.25rem;
}

/* ─────────────────────────────────────────────────────────────
   BUTTON ACCESSIBILITY
   ───────────────────────────────────────────────────────────── */

/* Buttons must be at least 44x44px for touch targets */
.btn {
  min-height: 44px;
  min-width: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 0.375rem;
  transition: all 0.2s ease;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  text-decoration: none;
}

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

.btn:active {
  transform: scale(0.98);
}

/* Ensure button text is readable */
.btn-primary,
.btn-success,
.btn-danger {
  color: #fff;
}

/* ─────────────────────────────────────────────────────────────
   IMAGE ACCESSIBILITY
   ───────────────────────────────────────────────────────────── */

/* All images must have alt text (enforced in HTML) */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Decorative images should have empty alt text */
img[aria-hidden="true"] {
  display: block;
}

/* ─────────────────────────────────────────────────────────────
   NAVIGATION ACCESSIBILITY
   ───────────────────────────────────────────────────────────── */

/* Navigation should be keyboard accessible */
nav {
  position: relative;
}

nav a,
nav button {
  display: inline-block;
  padding: 0.75rem 1rem;
  text-decoration: none;
  transition: all 0.2s ease;
}

nav a:focus-visible,
nav button:focus-visible {
  outline: 3px solid #0d6efd;
  outline-offset: 2px;
}

/* Active navigation indicator */
.nav-link.active {
  font-weight: 600;
  border-bottom: 2px solid #0d6efd;
}

/* ─────────────────────────────────────────────────────────────
   ARIA LIVE REGIONS
   ───────────────────────────────────────────────────────────── */

/* Live regions for dynamic content updates */
[aria-live] {
  position: relative;
}

[aria-live="polite"] {
  /* Screen readers will announce changes politely */
}

[aria-live="assertive"] {
  /* Screen readers will interrupt to announce changes */
}

/* ─────────────────────────────────────────────────────────────
   SCREEN READER ONLY CONTENT
   ───────────────────────────────────────────────────────────── */

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

.sr-only-focusable:active,
.sr-only-focusable:focus {
  position: static;
  width: auto;
  height: auto;
  overflow: visible;
  clip: auto;
  white-space: normal;
}

/* ─────────────────────────────────────────────────────────────
   REDUCED MOTION SUPPORT
   ───────────────────────────────────────────────────────────── */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ─────────────────────────────────────────────────────────────
   PRINT STYLES
   ───────────────────────────────────────────────────────────── */

@media print {
  .skip-to-main,
  .navbar,
  footer,
  .btn,
  .portfolio-overlay {
    display: none;
  }

  body {
    font-size: 12pt;
    color: #000;
  }

  a {
    text-decoration: underline;
  }

  h1, h2, h3, h4, h5, h6 {
    page-break-after: avoid;
  }

  p {
    orphans: 3;
    widows: 3;
  }
}

/* ─────────────────────────────────────────────────────────────
   HIGH CONTRAST MODE SUPPORT
   ───────────────────────────────────────────────────────────── */

@media (prefers-contrast: more) {
  body {
    color: #000;
  }

  a {
    text-decoration: underline;
    font-weight: 600;
  }

  .btn {
    border-width: 2px;
  }

  *:focus-visible {
    outline-width: 4px;
  }
}

/* ─────────────────────────────────────────────────────────────
   DARK MODE SUPPORT
   ───────────────────────────────────────────────────────────── */

@media (prefers-color-scheme: dark) {
  body {
    background-color: #1a1a1a;
    color: #e0e0e0;
  }

  .bg-light {
    background-color: #2a2a2a !important;
  }

  .text-muted {
    color: #a0a0a0 !important;
  }

  input,
  textarea,
  select {
    background-color: #2a2a2a;
    color: #e0e0e0;
    border-color: #444;
  }
}