/* ============================================
   PROFE ALEXIAI - Los 9 errores
   Material de consulta
   Mobile-first · Dark theme · Vanilla CSS
   ============================================ */

:root {
  --negro:       #0a0a0a;
  --negro-2:     #111111;
  --negro-3:     #1a1a1a;
  --magenta:     #D91A8A;
  --magenta-2:   #F472B6;
  --cyan-tech:   #5EEAD4;
  --naranja-meta:#FBBF24;
  --blanco:      #FFFFFF;
  --gris-1:      #E5E7EB;
  --gris-2:      #9CA3AF;
  --gris-3:      #374151;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  background: var(--negro);
  color: var(--blanco);
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 400;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--magenta); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--magenta-2); }
strong, b { font-weight: 600; }
::selection { background: var(--magenta); color: var(--blanco); }
:focus-visible { outline: 2px solid var(--magenta); outline-offset: 3px; }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.25rem;
}
@media (min-width: 768px) { .container { padding: 0 2rem; } }
@media (min-width: 1024px) { .container { padding: 0 3rem; } }

/* ============================================
   SKIP LINK
   ============================================ */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--magenta);
  color: var(--blanco);
  padding: 0.5rem 1rem;
  border-radius: 4px;
  font-size: 0.875rem;
  font-weight: 600;
  z-index: 200;
  transition: top 0.2s;
}
.skip-link:focus {
  top: 1rem;
  color: var(--blanco);
}

/* ============================================
   NAVBAR SUPERIOR
   ============================================ */
.navbar-top {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 50;
  padding: 1rem 1.25rem;
}
@media (min-width: 768px) { .navbar-top { padding: 1.25rem 2rem; } }
@media (min-width: 1024px) { .navbar-top { padding: 1.5rem 3rem; } }

.navbar-top__link {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 600;
  font-size: 0.8125rem;
  color: var(--gris-2);
  text-decoration: none;
  transition: color 0.2s;
  letter-spacing: 0.02em;
}
.navbar-top__link:hover { color: var(--magenta); }

/* ============================================
   HERO
   ============================================ */
.hero {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  padding: 6rem 1.25rem 3rem;
  position: relative;
}
@media (min-width: 768px) { .hero { padding: 6rem 2rem 3rem; } }
@media (min-width: 1024px) { .hero { padding: 8rem 3rem 4rem; max-width: 1200px; margin: 0 auto; } }

.hero__label {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 600;
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--magenta);
  margin-bottom: 1.5rem;
  display: block;
}

.hero__title {
  font-family: 'Clash Display', sans-serif;
  font-weight: 700;
  font-size: clamp(2.75rem, 8vw, 7rem);
  letter-spacing: -0.02em;
  line-height: 0.95;
  color: var(--blanco);
  margin-bottom: 1.5rem;
  max-width: 900px;
}

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

.hero__subtitle {
  font-size: 1.05rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.7);
  max-width: 680px;
}
@media (min-width: 768px) { .hero__subtitle { font-size: 1.15rem; } }

/* ============================================
   INDICE NAVEGABLE
   ============================================ */
.indice {
  padding: 2rem 0 4rem;
}

.indice__list {
  list-style: none;
  counter-reset: none;
}

.indice__item {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--gris-3);
  text-decoration: none;
  transition: color 0.2s;
}
.indice__list li:last-child .indice__item { border-bottom: none; }

.indice__num {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--gris-2);
  flex-shrink: 0;
  width: 2rem;
  transition: color 0.2s;
}

.indice__titulo {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 500;
  font-size: 1rem;
  color: var(--gris-1);
  transition: color 0.2s;
}
@media (min-width: 768px) { .indice__titulo { font-size: 1.05rem; } }

.indice__item:hover .indice__num,
.indice__item:hover .indice__titulo {
  color: var(--magenta);
}

/* ============================================
   BLOQUES DE ERROR
   ============================================ */
.errores {
  padding: 2rem 0 4rem;
}

.error-bloque {
  padding: 3.5rem 0;
  border-top: 1px solid var(--gris-3);
}
.error-bloque:first-child { border-top: none; }
@media (min-width: 768px) { .error-bloque { padding: 5rem 0; } }
@media (min-width: 1024px) { .error-bloque { padding: 6rem 0; } }

.error-bloque__titulo {
  font-family: 'Clash Display', sans-serif;
  font-weight: 700;
  font-size: clamp(1.5rem, 3.5vw, 2.5rem);
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--blanco);
  margin-bottom: 2rem;
  max-width: 700px;
}

.error-bloque__num {
  color: var(--gris-2);
  margin-right: 0.35em;
}

.error-bloque__seccion {
  margin-bottom: 1.75rem;
  max-width: 700px;
}
.error-bloque__seccion:last-of-type { margin-bottom: 0; }

.error-bloque__label {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 600;
  font-size: 1rem;
  color: var(--cyan-tech);
  margin-bottom: 0.5rem;
}

.error-bloque__seccion p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--gris-1);
}
@media (min-width: 768px) { .error-bloque__seccion p { font-size: 1.05rem; } }

.error-bloque__seccion code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.88em;
  background: var(--negro-2);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  color: var(--magenta-2);
}

.error-bloque__seccion a {
  position: relative;
  color: var(--magenta);
  text-decoration: none;
}
.error-bloque__seccion a::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--magenta);
  transition: width 0.25s ease;
}
.error-bloque__seccion a:hover::after { width: 100%; }

.error-bloque__coste {
  font-style: italic;
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--gris-2);
  margin-top: 1.25rem;
  max-width: 700px;
}
@media (max-width: 767px) { .error-bloque__coste { font-size: 0.8125rem; } }

/* ============================================
   CIERRE
   ============================================ */
.cierre {
  padding: 5rem 0 3rem;
}

.date-notice {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--gris-2);
  max-width: 700px;
  margin-bottom: 3.5rem;
}
@media (max-width: 767px) { .date-notice { font-size: 0.8125rem; } }

.quote-final {
  margin: 0;
  padding: 0;
}

.quote-final__text {
  font-family: 'Clash Display', sans-serif;
  font-weight: 600;
  font-size: clamp(1.5rem, 3.5vw, 2.5rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--blanco);
  max-width: 700px;
}

.quote-final__line { display: block; }

.quote-final__rule {
  width: 50px;
  height: 2px;
  background: var(--magenta);
  border: none;
  margin-top: 2rem;
}

/* ============================================
   NAV VOLVER
   ============================================ */
.nav-volver {
  padding: 3rem 0 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
}

.nav-volver__link {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 500;
  font-size: 0.875rem;
  color: var(--gris-2);
  text-decoration: none;
  transition: color 0.2s;
}
.nav-volver__link:hover { color: var(--magenta); }

/* ============================================
   SITE FOOTER
   ============================================ */
.site-footer {
  padding: 3rem 0 1rem;
  text-align: center;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.site-footer__brand {
  font-family: 'Clash Display', sans-serif;
  font-weight: 600; font-size: 1rem;
  color: var(--gris-1); margin-bottom: 0.5rem;
}
.site-footer__note { font-size: 0.85rem; color: var(--gris-2); margin-bottom: 0.25rem; }
.site-footer__note a { color: var(--gris-2); text-decoration: underline; text-underline-offset: 2px; }
.site-footer__note a:hover { color: var(--gris-1); }

/* ============================================
   GSAP / REDUCED MOTION / PRINT
   ============================================ */
.anim-fade-up { opacity: 0; transform: translateY(20px); }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
  .anim-fade-up { opacity: 1; transform: none; }
}

@media print {
  body { background: #fff; color: #000; }
  .navbar-top { display: none; }
}