/* Eye Comfort & Accessibility Utilities */

/* Blue Light Filter - Integrates with system Night Shift/Night Light */
@media (prefers-color-scheme: light) {
  :root {
    /* Subtle blue light reduction during daytime */
    --blue-light-overlay: rgba(255, 243, 224, var(--blue-light-filter-intensity));
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    /* Enhanced blue light reduction at night */
    --blue-light-overlay: rgba(255, 243, 200, calc(var(--blue-light-filter-intensity) * 0.8));
  }
}

/* Apply blue light filter globally */
.eye-comfort-enabled::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--blue-light-overlay);
  pointer-events: none;
  z-index: 9999;
  transition: background-color 0.3s ease;
}

/* Reading-focused blue light filter */
.reader-blue-light-filter {
  position: relative;
}

.reader-blue-light-filter::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--blue-light-overlay);
  pointer-events: none;
  border-radius: inherit;
}

/* Eye strain reduction background patterns */
.eye-strain-minimal .reader-content {
  background-image:
    radial-gradient(circle at 20% 80%, rgba(120, 119, 198, 0.03) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.03) 0%, transparent 50%);
  background-size: 400px 400px;
  background-position: 0% 0%, 100% 100%;
}

/* WCAG 2.2 AA Compliance Utilities */

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --text-primary: #000000;
    --bg-primary: #FFFFFF;
    --border-color: #000000;
  }
}

/* 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;
    scroll-behavior: auto !important;
  }
}

/* Focus indicators - Enhanced for accessibility */
.focus-visible:focus-visible {
  outline: 3px solid var(--primary-color);
  outline-offset: 2px;
  border-radius: 4px;
}

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

.sr-only:focus {
  position: static;
  width: auto;
  height: auto;
  padding: inherit;
  margin: inherit;
  overflow: visible;
  clip: auto;
  white-space: normal;
}

/* Minimum touch targets - 48x48px minimum */
.btn-accessible,
.interactive-element {
  min-width: 48px;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Color contrast utilities */
.text-high-contrast {
  color: var(--text-primary);
}

.bg-high-contrast {
  background: var(--bg-primary);
}

/* Reading performance optimizations */
.reading-optimized {
  /* Scientifically proven reading parameters */
  font-size: var(--reader-font-size);
  line-height: var(--reader-line-height);
  max-width: var(--reader-max-width);
  margin: 0 auto;
  text-align: justify;
  hyphens: auto;
}

/* Eye tracking friendly layouts */
.eye-tracking-friendly .reader-content p {
  /* Prevent excessive line length variations */
  text-justify: inter-word;
  widows: 2;
  orphans: 2;
}

/* Performance monitoring utilities */
.performance-indicator {
  /* Subtle performance hints for development */
  position: fixed;
  bottom: 10px;
  right: 10px;
  background: rgba(0, 0, 0, 0.8);
  color: white;
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 12px;
  z-index: 10000;
}