<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
#parent {
width: 300px;
height: 90px;
background-color: #666;
overflow-x: auto;
overflow-y: hidden;
}
#childWrapper {
list-style: none;
width: 450px;
height: 80px;
margin: 0;
padding: 0;
overflow: hidden;
}
#childWrapper > li {
float: left;
width: 150px;
height: 80px;
background-color: #55c974;
}
#childWrapper > li:nth-child(even) {
background-color: #d4ffdd;
}
</style>
</head>
<body>
<div id="parent">
<ul id="childWrapper">
<li>Box 1</li>
<li>Box 2</li>