Table style seems not support well

[ZishunYu]

Hello, I've been using your theme for a while and it looks awesome. But there is a thing bugs me quite long time which is the table style.

It seems that the table border cannot be shown and the margin is also too small (There is no margin between "Caption" and "A" where it suppose to be.)

Another issue is it seems that I cannot make tables centering but I am not sure whether I am doing the correct way, shown as following

<center> table <\center>

Thank you very much