04.ColorizeTable

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Demo</title>
</head>
<body>
    <table>
        <tr><th>Name</th><th>Town</th></tr>
        <tr><td>Eve</td><td>Sofia</td></tr>
        <tr><td>Nick</td><td>Varna</td></tr>
        <tr><td>Didi</td><td>Ruse</td></tr>
        <tr><td>Tedy</td><td>Varna</td></tr>
    </table>
    <button onclick="colorize()">Colorize</button>
    <script>
        function colorize() {
            let oddTableCells = document.querySelectorAll('tr:nth-child(even)');
            for(let i = 0; i < oddTableCells.length; i++) {
                oddTableCells[i].style.backgroundColor = 'teal';
            }
        }
    </script>
</body>
</html>