/* Transmitter sweep: concentric wavefronts leaving a point source.
   Chosen over a generic spinner because it depicts the thing being computed —
   signal propagating outward from a station. Every colour is a theme token. */
.rl { position: relative; width: var(--rl-size, 64px); height: var(--rl-size, 64px); flex: none; }
.rl i {
  position: absolute; inset: 0; margin: auto;
  width: 100%; height: 100%; border-radius: 50%;
  border: 2px solid var(--hf-accent-interactive);
  opacity: 0; transform: scale(0.18);
  animation: rl-wave 2.4s cubic-bezier(0.2, 0.6, 0.35, 1) infinite;
}
.rl i:nth-child(2) { animation-delay: 0.8s; }
.rl i:nth-child(3) { animation-delay: 1.6s; }
.rl b {
  position: absolute; inset: 0; margin: auto;
  width: 22%; height: 22%; border-radius: 50%;
  background: var(--hf-accent-interactive);
  animation: rl-key 2.4s steps(1, end) infinite;
}
@keyframes rl-wave {
  0%   { opacity: 0;    transform: scale(0.18); }
  12%  { opacity: 0.85; }
  100% { opacity: 0;    transform: scale(1); }
}
@keyframes rl-key {
  0%, 12%  { opacity: 1; }
  13%, 100% { opacity: 0.45; }
}
@media (prefers-reduced-motion: reduce) {
  /* Motion is the whole point, so replace it rather than freeze it: a steady
     pulse still reads as "working" without radial movement. */
  .rl i { animation: none; opacity: 0.3; transform: scale(0.7); }
  .rl i:nth-child(3) { transform: scale(1); opacity: 0.15; }
  .rl b { animation: rl-fade 1.6s ease-in-out infinite; }
}
@keyframes rl-fade { 0%,100% { opacity: 1; } 50% { opacity: 0.35; } }