Basically, this will give you complete control over the grid using CSS so that you can modify the layout as any way you wish. However, you will need have pretty good CSS knowledge to be able to do it yourself.
For the post layout, you will need to edit some templates and css. You can turn on "Show template names in HTML" from admincp > options > general settings.
Then you can use your browser's inspector (press F12) to find out the template name.
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