React Js conditionally applying className

<!DOCTYPE html>
<html>

<body>
    <div id="app"></div>
    <script type="text/babel">
        function App() {
            const [isActive, setIsActive] = React.useState(true);
            return (
                <div className='container'>
                    <div className={isActive ? 'active' : 'inactive'}>
                        <h3>React Js Conditional Rendering ClassName</h3>
                    </div>
                </div >
            );
        }

ReactDOM.render(<App />, document.getElementById("app"));
    </script>
    <style>
        * {
            box-sizing: border-box;
        }

body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
        }

.container {
            margin: 0 auto;
            width: 600px;
            text-align: center;
            box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.12), 0 2px 4px 0 rgba(0, 0, 0, 0.24);
            padding: 20px;
        }

.active {
            background-color: #ff4081;
            color: #fff;
            padding: 20px;
            border-radius: 5px;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
            transition: background-color 0.3s ease;
        }

.inactive {
            background-color: #f5f5f5;
            color: #333;
            padding: 20px;
            border-radius: 5px;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
            transition: background-color 0.3s ease;
        }

h3 {
            margin: 0;
            font-size: 24px;
        }
    </style>
</body>

</html>

 
<!DOCTYPE html>
<html>
​
<head>
    <meta charset="UTF-8" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.2/umd/react.production.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.2/umd/react-dom.production.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.26.0/babel.min.js"></script>
</head>
​
<body>
    <div id="app"></div>
    <script type="text/babel">
        function App() {
            const [isActive, setIsActive] = React.useState(true);
            return (
                <div className='container'>
                    <div className={isActive ? 'active' : 'inactive'}>
                        <h3>React Js Conditional Rendering ClassName</h3>
                    </div>
                </div >
            );
        }
​
        ReactDOM.render(<App />, document.getElementById("app"));
    </script>
    <style>
        * {
            box-sizing: border-box;
        }
​
        body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
        }
​
        .container {
            margin: 0 auto;
            width: 600px;
            text-align: center;
            box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.12), 0 2px 4px 0 rgba(0, 0, 0, 0.24);
            padding: 20px;
        }
​
        .active {
            background-color: #ff4081;
            color: #fff;
            padding: 20px;
            border-radius: 5px;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
            transition: background-color 0.3s ease;
        }
​
        .inactive {
            background-color: #f5f5f5;
            color: #333;
            padding: 20px;
            border-radius: 5px;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
            transition: background-color 0.3s ease;
        }
​
        h3 {
            margin: 0;
            font-size: 24px;
        }
    </style>
</body>
​
</html>