Three-dot loader

.btn-083 {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-width: 120px;
  height: 42px;
  background: #111827;
  border: 0;
  border-radius: 999px;
  cursor: progress
}
.btn-083 i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #fff;
  animation: btn-083-b .9s infinite ease-in-out
}
.btn-083 i:nth-child(2) {
  animation-delay: .15s
}
.btn-083 i:nth-child(3) {
  animation-delay: .3s
}
@keyframes btn-083-b {
  0%,80%,100% {
    transform: translateY(0);
    opacity: .4
  }
  40% {
    transform: translateY(-6px);
    opacity: 1
  }
}
.btn-083:focus-visible {
  outline: 2px solid #111827;
  outline-offset: 3px
}
@media (prefers-reduced-motion: reduce) {
  .btn-083, .btn-083 * { animation: none; transition: none; }
}

<button class="btn-083" disabled aria-label="Loading"><i></i><i></i><i></i></button>