you have to put the styling in between the tags like this
<pre><!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Page title</title>
</head>
<style>
*{
margin:0;
padding:0;
}
body{
background:#222;
color:#fff;
font-family:system-ui;
}
.crud{
width:80%;
margin:auto;
}
.header{
text-align:center;
margin:10px 0;
text-transform:uppercase;
}
.inputs{
width:100%;
border:none;
}
</style>
<body>
<div class="crud">
<div class="header">
<h2>cruds</h2>
<p>product management system</p>
</div>
<div class="inputs">
</div>
</div>
</body>
</html>
link to how to use css
How to add CSS[
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