We have run the code that you had provided, but it seems that there are missing some stylesheets. This is a video
as a part of the testing. In general, if you would like to center the text in the items, you can make it by the property "text-align" as the following:
If you would like to achieve some different behavior, we would like to ask you to provide us with your project.
We would like also recommend you some improvements for your project - a good practice is avoiding the usage of inline CSS if it is not necessary. Instead of that you can set the styles property in separate file which is appreciable easier for further maintenance. Please, find a sample project in the attachment based on the code that you provided.
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