website/conservancy/supporters/static/css/buttonradio.css

.button-select {
  display: grid;
  gap: 0.5rem;
  grid-template-columns: repeat(auto-fill, minmax(5rem, 1fr));
}

.button-select label > span {
  text-align: center;
  display: inline-block;
  user-select: none;
  padding: 0.5rem 0;
  width: 100%;
  background: #ddd;
  border-radius: 4px;
  border: 1px solid transparent;
}

.button-select label input {
  opacity: 0;
  position: absolute;
}

/* Wish we could use :has reliably. */
.button-select label input:focus + span {
  border-color: #eee;
  outline: 2px solid #666;
}

.button-select label input:checked + span {
  color: white;
  background: #666;
}