<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
</head>
<body>
  <div id="container">
    <div class="box a">Alphabet</div>
    <div class="box b">Banana</div>
    <div class="box c">Crayons</div>
    <div class="box a">Dinosaurs</div>
    <div class="box b">Eggplant</div>
    <div class="box c">Foundation</div>
    <div class="box a">Ghosts</div>
    <div class="box b">Happy</div>
    <div class="box c">Igloo</div>
    <div class="box a">Janitors</div>
    <div class="box b">Kittens</div>
    <div class="box c">Lasso</div>
    <div class="box a">Magic 8-ball</div>
    <div class="box b">Nincompoop</div>
    <div class="box c">Orange</div>
    <div class="box a">Petunia</div>
    <div class="box b">Quality</div>
    <div class="box c">Rancid</div>
    <div class="box a">Shoelace</div>
    <div class="box b">Terydactyl</div>
    <div class="box c">Umbrella</div>
    <div class="box a">Valentine</div>
    <div class="box b">Westward</div>
    <div class="box c">Xylophone</div>
	</div>
</body>
</html>
body > div {
  display: flex;
  height: 200px;
  flex-direction: row;
  flex-wrap: wrap;
}
div >  div {
  flex: 10%;
  min-width: 0;
}


#container > .box{ 
  border: 1px solid #eee;
}
.box {
  background-color: #fff;
}
.box:nth-child(2n) {
  background-color: #ccc;
}
.box:nth-child(3n) {
  background-color: #999;
}

External CSS

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External JavaScript

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