/* ==========================================================================
   QUÉDATE - Estilos Base y Reset Accesible
   ========================================================================== */

/* Reset respetuoso con accesibilidad */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 100%;
  scroll-behavior: smooth;
}

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

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text-main);
  background-color: var(--color-bg-base);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Enlace para saltar al contenido principal (Skip-link obligatorio) */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--color-accent);
  color: #ffffff;
  padding: 0.85rem 1.5rem;
  font-weight: 700;
  text-decoration: none;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  z-index: 9999;
  transition: top 0.2s ease-in-out;
  box-shadow: var(--shadow-lg);
}

.skip-link:focus {
  top: 0;
  outline: 3px solid #ffffff;
  outline-offset: 2px;
}

/* Foco de teclado accesible universal con halo suave */
:focus-visible {
  outline: var(--focus-outline-width) solid var(--color-border-focus) !important;
  outline-offset: var(--focus-outline-offset) !important;
  box-shadow: 0 0 0 5px rgba(0, 86, 179, 0.2) !important;
}

/* Jerarquía de encabezados con tamaños y contraste claros */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-headings);
  line-height: var(--line-height-heading);
  color: var(--color-primary);
  font-weight: 800;
  margin-bottom: 0.85rem;
}

h1 {
  font-size: var(--font-size-3xl);
  letter-spacing: -0.025em;
}

h2 {
  font-size: var(--font-size-2xl);
  letter-spacing: -0.015em;
  margin-top: 1.75rem;
}

h3 {
  font-size: var(--font-size-xl);
  letter-spacing: -0.01em;
  margin-top: 1.35rem;
}

h4 {
  font-size: var(--font-size-lg);
  margin-top: 1.15rem;
}

p {
  margin-bottom: 1.25rem;
  max-width: var(--max-reading-width);
}

a {
  color: var(--color-secondary);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 2px;
  transition: var(--transition-default);
  font-weight: 600;
}

a:hover, a:focus {
  color: var(--color-primary);
  text-decoration-thickness: 3px;
}

ul, ol {
  margin-left: 1.75rem;
  margin-bottom: 1.35rem;
  max-width: var(--max-reading-width);
}

li {
  margin-bottom: 0.6rem;
  line-height: 1.65;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-md);
}

/* Contenedor central accesible */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* Regla visual de lectura (guía de seguimiento) */
#reading-guide-line {
  display: none;
  position: fixed;
  left: 0;
  right: 0;
  height: 30px;
  background-color: rgba(255, 235, 59, 0.28);
  border-top: 2px dashed #f57f17;
  border-bottom: 2px dashed #f57f17;
  pointer-events: none;
  z-index: 9998;
}

body.reading-guide-active #reading-guide-line {
  display: block;
}

/* Utilidades de Accesibilidad */
.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;
}