Why incorrectly displays a frame around the Grid?

Hello!
Tell me, please, why the box around grida wider and smaller in height of the grid?
<!doctype html>
<html lang="en">
the <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">
 <link rel="stylesheet" href="style.css">
<title>Document</title>
</head>
the <body>
<div class="container">
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item"></div>
 <div class="item-b"></div>
</div>
</body>

*{
 margin: 0;
 padding: 0;
}
.container {
 gap: 15px 16px;
 display: grid;
 border: 1px solid black;
 grid-template-columns: 40px 50px 40px 50px 40px ;
 grid-template-rows: 25% 100px 30px;
}
.item{
 background-color: #F00;
}
.item-b {
 background-color: #00F;
 grid-column-start: 1;
 grid-column-end: span 4;
 grid-row-start: 2;
 grid-row-end: 4;
}

5e989ea073a35807876482.png
April 19th 20 at 12:23
0 answer

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