WebStorm 6 FlexBox

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Flex_basics</title>
    <link rel="stylesheet" href="style.css">

</head>
<body>
    <div id="cotainer">
        <div class="item"><h3>Item 1</h3></div>
        <div class="item"><h3>Item 2</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
        <div class="item"><h3>Item 3</h3></div>
    </div>
</body>
</html>


.item{
    background: lightgrey;
    border: #cccccc solid 1px;
    padding: 1rem;
    text-align: center;
    flex: 1;
    margin: 0.75rem;
}
.item:first-child
{
    flex: 1;
}
#cotainer{
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;

}
body{
    background-color: turquoise;
}