/* PLAY-DOS · base común de los prototipos. Retícula 80×25 de celdas 9×16 (PRD §7). */
@font-face {
  font-family: 'IBM VGA';
  src: url('../fuentes/WebPlus_IBM_VGA_9x16.woff') format('woff');
  font-display: block;
}
:root { --n: 1; }
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
#pantalla {
  position: relative;
  flex: none;
  width: calc(720px * var(--n));
  height: calc(400px * var(--n));
  font-family: 'IBM VGA', monospace;
  font-size: calc(16px * var(--n));
  line-height: calc(16px * var(--n));
  white-space: pre;
  user-select: none;
  -webkit-font-smoothing: none;
  font-kerning: none;
  font-variant-ligatures: none;
  overflow: hidden;
}
body.modo40 #pantalla { width: calc(360px * var(--n)); }
.fila { height: calc(16px * var(--n)); overflow: hidden; }
.fila span { display: inline-block; height: 100%; vertical-align: top; }
/* Cursor de DOS: subrayado de dos líneas que parpadea */
.cur { box-shadow: inset 0 calc(-2px * var(--n)) 0 0 currentColor; animation: parpadeo 1.07s steps(1) infinite; }
@keyframes parpadeo { 50% { box-shadow: none; } }
@media (prefers-reduced-motion: reduce) { .cur { animation: none; } }
iframe.juego { position: absolute; border: 0; background: #000; }