JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Задание 2</title>
<link rel="stylesheet" type="text/css" href="task2.css" media="all">
</head>
<body>
 <h1>Заголовок</h1>
 <div class="box">
  Содержание блока
 </div>
</body>
</html>

CSS

body{
 padding: 2px;
}

.box{
 background: #c9e39c;
 border: 1px solid #a3d869;
 -webkit-box-shadow: 0px 0px 5px #ccc;
 -moz-box-shadow: 0px 0px 5px #ccc;
 box-shadow: 0px 0px 5px #ccc;
 padding: 10px;
 -webkit-border-bottom-right-radius: 6px;
 -webkit-border-bottom-left-radius: 6px;
 -moz-border-radius-bottomright: 6px;
 -moz-border-radius-bottomleft: 6px;
 border-bottom-right-radius: 6px;
 border-bottom-left-radius: 6px; 
 font-size: 14px;
 font-family: Arial;
}


h1{
 background: #c9e39c;
 border: 1px solid #a3d869;
 border-bottom: 0;
 -webkit-border-top-right-radius: 6px;
 -webkit-border-top-left-radius: 6px;
 -moz-border-radius-topright: 6px;
 -moz-border-radius-topleft: 6px;
 border-top-right-radius: 6px;
 border-top-left-radius: 6px; 
 display: inline-block;
 margin: 0 0 -1px 0;
 position: relative;
 font-size: 17px;
 font-weight: bold;
 color: #000;
 font-family: Arial;
 line-height: 30px;
 height: 30px;
 padding: 0 10px;
 -moz-box-shadow: 0 -2px 5px 0 #ccc; 
}