Tables carry some very simple styles just to make them feel consistent, they have a width of 100% so they fill their parent element.
There are several additional classes that can be applied to tables:
table-borderedapply a border to the table
table-hoverhighlight row on hover
table-stripedalternating row background colors
table-headedadd background color to the header
All colors are defined in variables. Example with all additional classes.
Tables dont work well on smaller screens, one way of fixing this is to wrap the table in a div with auto scrolling. This will enable the table to take up as much space as needed and enable you to scroll left and right.