remove background color table cell

You might need to add an !important at the end of your CSS rules if it’s going into your style.css
If the shortcodes ultimate stylesheet is loading after your style.css, it can override whatever custom styling you’ve added.
Adding your styling to the shortcodes ultimate Settings > Custom CSS should allow it to re-style as intended, but I have 8 instances in my plugin settings custom CSS where I still had to use !important.

I did, but the styling which comes with the plugin has the !important already is use.

Which specific shortcode/element/class are you trying to restyle?

the table function, i want to change the background color and borders

I was able to change them using the SU Settings > Custom CSS area using this (beware, it’s ugly):

.su-table td {
	padding: 1em 2em !important;
	border: 1px solid #666 !important;
	background: #97cfd4 !important;
}
.su-table .su-even td {
	background: #d0d0d0 !important;
}

The Custom CSS area overrides the SU default styling because it always loads it after, even if it’s denoted as !important.

Thanks, didn’t think about that!