Reduce padding in main menu so that we can add more menu items

How do we reduce padding in main menu so that we can add more menu items, screen shot attached

Hi amarjit,
You can add the following CSS code to the Backend > site template styles > gk_archi - Default > Advanced settings tab > custom CSS code:

.gkMainMenu > .gkmenu.level0 > li + li {
    margin-left: 30px;
}

Can you post a link to the site?