Harmony Row

<div class="nuda-cpk2-harmony-row" role="radiogroup" aria-label="Palette harmony">
  <button type="button" class="nuda-cpk2-harmony-row__swatch is-checked" role="radio"
          aria-checked="true" aria-label="Base, hue 262 degrees" style="background:#9d6dff">
    <svg class="nuda-cpk2-harmony-row__check" viewBox="0 0 24 24" fill="none"
         stroke="currentColor" stroke-width="3" stroke-linecap="round"
         stroke-linejoin="round" aria-hidden="true">
      <path d="M20 6 9 17l-5-5" />
    </svg>
  </button>
  <button type="button" class="nuda-cpk2-harmony-row__swatch" role="radio"
          aria-checked="false" aria-label="Analogous, hue 292 degrees"
          style="background:#c56dff"></button>
  <!-- 3 more harmony swatches -->
</div>

.nuda-cpk2-harmony-row {
  display: flex;
  gap: 6px;
  padding: 10px;
  background: rgba(255,255,255,.02);
  border: 1px solid rgba(255,255,255,.06);
  border-radius: 12px;
  width: 100%;
  max-width: 260px;
}

.nuda-cpk2-harmony-row__swatch {
  position: relative;
  flex: 1;
  aspect-ratio: 1;
  min-width: 44px;
  min-height: 44px;
  border: 0;
  border-radius: 8px;
  cursor: pointer;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.1);
  transition: transform .2s cubic-bezier(.34,1.56,.64,1);
  animation: _nuda-cpk2harmonyrow .45s cubic-bezier(.16,1,.3,1) both;
}

.nuda-cpk2-harmony-row__swatch:nth-child(2) {
  animation-delay: .05s;
}

.nuda-cpk2-harmony-row__swatch:nth-child(3) {
  animation-delay: .1s;
}

.nuda-cpk2-harmony-row__swatch:nth-child(4) {
  animation-delay: .15s;
}

.nuda-cpk2-harmony-row__swatch:nth-child(5) {
  animation-delay: .2s;
}

.nuda-cpk2-harmony-row__swatch:hover {
  transform: translateY(-3px);
}

.nuda-cpk2-harmony-row__swatch.is-checked {
  box-shadow: inset 0 0 0 2px #0a0a0a,0 0 0 2px #e4ff54;
}

.nuda-cpk2-harmony-row__swatch:focus-visible {
  outline: 2px solid #e4ff54;
  outline-offset: 2px;
}

.nuda-cpk2-harmony-row__check {
  position: absolute;
  inset: 0;
  margin: auto;
  width: 16px;
  height: 16px;
  color: #fafafa;
  filter: drop-shadow(0 1px 2px rgba(0,0,0,.6));
}

@keyframes _nuda-cpk2harmonyrow {
  from {
    opacity: 0;
    transform: translateY(6px) scale(.8);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-motion:reduce) {
  .nuda-cpk2-harmony-row__swatch {
    animation: none;
    transition: none;
  }
}