JSFiddle - React, Tailwind, and code Playground

HTML

<label class="jbprice-row jbprice-row-0">white</label>
<label class="jbprice-row jbprice-row-1">black</label>
<label class="jbprice-row jbprice-row-2">white</label>
<label class="jbprice-row jbprice-row-3">black</label>

CSS

.jbprice-row {
    display: block;
}
.jbprice-row:nth-child(2n) {
    background: black;
    color: white;
}