Step1: You can add or change the background color for the whole table. The background color appears underneath any fill color that is applied to the table cells.
Step2: Click a cell in the table.
Step3: Go to Table Tools> Design, and then in the Table Styles group, click the arrow next to Shading, and then point to Table Background.
Step4: Click the color that you want, or to choose no color, click No Fill.
Step5: To change to a color that is not shown in the Theme Colors list, click More Fill Colors, and then either click the color that you want on the Standard tab, or mix your own color on the Custom tab. Custom colors and colors on the Standard tab are not updated if you later change the document theme.