/* layout.css
   Rozvržení kreslící plochy (board), SVG vrstev a mřížky bodů. */
.board{
  position:relative; aspect-ratio:1/1;
  width:min(640px, 100%); margin-inline:auto;
  border-radius:16px; overflow:hidden; user-select:none;
  /* Povolit kreslení gest bez posouvání stránky */
  touch-action: none;
  background:
    radial-gradient(120px 80px at 10% 10%, rgba(255,255,255,.04), transparent 60%),
    linear-gradient(180deg, rgba(255,255,255,.03), rgba(0,0,0,.05)),
    var(--panel);
  box-shadow:
    inset 0 0 0 1px rgba(255,255,255,.04),
    0 20px 60px rgba(0,0,0,.45);
}
.grid{
  position:absolute; inset:0;
  display:grid;
  padding: clamp(var(--grid-pad-min), var(--grid-pad-clamp), var(--grid-pad-max));
  gap: clamp(var(--grid-gap-min), var(--grid-gap-clamp), var(--grid-gap-max));
}
svg.lines{ position:absolute; inset:0; pointer-events:none; filter: drop-shadow(0 6px 18px rgba(0,0,0,.45)) }