index.html

<!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">
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    <script src="js/main.js" defer></script>

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    <title>Список дел</title>
</head>
<body>
    <div class="card w-50 mx-auto mt-5">
        <div class="card-body">
            <h1 class="card-title">Список дел</h1>
            <div class="header">
                <button type="button" class="btn btn-secondary btn-add">Добавить</button>
            </div>
            <div class="list">
                
            </div>
        </div>
    </div>
</body>
</html>