.fl-board {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  width: min(92vw, 340px);
  aspect-ratio: 1 / 1;
  background: #0f1b2d;
  border: 3px solid #2b3f5c;
  border-radius: 10px;
  padding: 3px;
  gap: 2px;
  touch-action: none;
}
.fl-cell {
  background: #16263c; border-radius: 4px; position: relative;
  display: grid; place-items: center;
}
.fl-cell.ep::after {
  content: ""; width: 46%; height: 46%; border-radius: 50%;
  background: var(--c); box-shadow: 0 0 6px var(--c);
}
.fl-cell.path { background: var(--c); }
.fl-cell.head::after {
  content: ""; position: absolute; inset: 30%; border-radius: 50%;
  background: #fff; opacity: .85;
}