No, that should not happen. To change the table border color you must
have the following code inside your CSS stylesheet.
border: 1px solid #hexcol;
So, either inside your code this kind of code is present to update the table's default border value. Otherwise, you're un aware of any CSS code that is causing this effect. However, if it happens any way. You can write another line of code for this table, to keep its initial value (black) or any other value that you want it to take independant of its parent's font or color properties. Use the above CSS code, and add the color property to the table's border. You can pass the value
to the border property, to cause the border to have the initial value of black.