How to change the default setting for the element?

Dear all,

I met a problem, when I creat a <table> element, the cell margin is 5pt, and the line thickness is 1pt, like the folloing:

The problem is how to change the default setting for the <table> element? Where the primary setting? Can I define it in the stylesheet?

Using APP Source? or add new table element? or...? How?

Also for other default table attribute, such as the row-height, the column-width...

I was troubled by this problem for a long time, but still no clue. Your assistance will be highly appreciated in this regard.

Thanking you!