/* Diseño sencillo, sin librerías ni fuentes externas. */
:root { color-scheme: light; --azul: #173c87; --borde: #dce1e8; }
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: #242a34; background: #fff; font-family: Arial, Helvetica, sans-serif; line-height: 1.6; }
a { color: var(--azul); }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
a:focus-visible, button:focus-visible { outline: 3px solid #e89624; outline-offset: 4px; }
.contenedor { width: min(1080px, 90%); margin: 0 auto; }
.cabecera { border-bottom: 1px solid var(--borde); }
.cabecera-interior { min-height: 100px; display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 14px 0; }
.logo { display: block; width: 90px; height: auto; }
nav { display: flex; align-items: center; flex-wrap: wrap; gap: 20px; }
nav a { font-size: 14px; text-decoration: none; }
nav a:hover { text-decoration: underline; }
.boton { display: inline-block; padding: 9px 16px; border: 1px solid var(--azul); border-radius: 4px; background: var(--azul); color: #fff; font-size: 14px; line-height: 1.5; text-decoration: none; cursor: pointer; }
.boton:hover { background: #102b62; }
.boton-secundario { background: #fff; color: var(--azul); }
.boton-secundario:hover { background: #edf2fc; }
.hero { min-height: 300px; display: flex; align-items: center; justify-content: center; padding: 65px 20px; background: #f3f6fb; text-align: center; border-bottom: 1px solid var(--borde); }
h1 { max-width: 850px; margin: 0; color: var(--azul); font-size: clamp(30px, 4.5vw, 48px); line-height: 1.2; }
h2 { margin: 0 0 10px; font-size: 28px; line-height: 1.3; }
.material { padding: 48px 0; }
.introduccion { max-width: 760px; margin: 0 0 28px; color: #5b6471; font-size: 15px; }
.galeria { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px; align-items: start; }
.tarjeta { border: 1px solid var(--borde); border-radius: 4px; overflow: hidden; background: #fff; }
.tarjeta-contenido { padding: 20px; }
.numero { margin: 0 0 8px; font-size: 12px; text-transform: uppercase; letter-spacing: 1px; color: #687385; }
.tarjeta h3 { margin: 0 0 10px; font-size: 20px; line-height: 1.35; color: var(--azul); }
.tema { margin: 0 0 16px; color: #596373; font-size: 14px; }
.captura { display: block; width: 100%; height: auto; border-top: 1px solid var(--borde); }
.referencia { padding: 28px; border: 1px solid var(--borde); margin-top: 36px; background: #f8f9fb; }
.referencia h2 { font-size: 22px; }
.referencia p { margin: 8px 0 18px; }
footer { border-top: 1px solid var(--borde); padding: 24px 0; font-size: 13px; color: #626b78; }
footer p { margin: 0 0 10px; }
footer a { display: inline-block; }
dialog { width: min(900px, 96vw); max-height: 94vh; padding: 0; border: 1px solid var(--borde); border-radius: 4px; }
dialog::backdrop { background: rgba(0, 0, 0, .78); }
.visor-barra { position: sticky; top: 0; display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 16px; background: #fff; border-bottom: 1px solid var(--borde); }
.visor-barra h2 { margin: 0; font-size: 17px; }
.visor-imagen { display: block; max-width: 100%; height: auto; margin: 0 auto; }
.sin-scroll { overflow: hidden; }
@media (max-width: 620px) {
  .cabecera-interior { gap: 12px; }
  .logo { width: 70px; }
  nav { gap: 10px; justify-content: flex-end; }
  nav a { font-size: 13px; }
  nav .boton { padding: 8px 11px; }
  .hero { min-height: 250px; padding: 50px 20px; }
  .material { padding: 32px 0; }
  .galeria { grid-template-columns: 1fr; gap: 24px; }
  .referencia { padding: 20px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }