JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrap">
    <div>Item 1</div>
    <div>Item 2</div>
    <div>Item 3</div>
    <div>Item 4</div>
    <div>Item 5</div>
    <div>Item 6</div>
    <div>Item 7</div>
    <div>Item 8</div>
    <div>Item 9</div>
    <div>Item 10</div>
    <div>Item 11</div>
    <div>Item 12</div>
    <div>Item 13</div>
    <div>Item 14</div>
    <div>Item 15</div>
    <div>Item 16</div>
    <div>Item 17</div>
    <div>Item 18</div>
    <div>Item 19</div>
    <div>Item 20</div>
    <div>Item 21</div>
</div>
<div class="next">Next</div>
<div class="prev">Prev</div>

JavaScript

$("#wrap > div").slice(0,7).css("background","yellow");
$("#wrap > div").slice(7,14).css("background","red");
$("#wrap > div").slice(14,21).css("background","blue");