Untitled

<!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">
<link rel="stylesheet" href="style.css" type="text/css" />
<title>Document</title>
<style type="text/css">
.category-block {
max-width: 768px;
margin:0 auto;
overflow:hidden;
}
.flex-block {
display:flex;
flex-direction: row;
align-items: stretch;
}
.flex-block img {
width: 100%;
}
</style>
</head>
<body>

<div class="category-block">
    <div class="flex-block">
        <div class="flex-block__area">
            <img src="1-img.jpg"></img>
        </div>
         <div class="flex-block__area">
            <img src="2-img.jpg"></img>
        </div>
         <div class="flex-block__area">
            <img src="3-img.jpg"></img>
        </div>
    </div>
</div>

</body>
</html>