Customizer > Layout > Secondary Navigation –> Menu item width. Reduce this to remove the left and right spacing.
Or you can change the Colors > Secondary Navigation to remove the Background hover color and just change the text color. This is the better option.
One thing I eager to know that the trend icon (svg) is that icon free to use? Or copyrighted one? Sorry to ask this but I can’t understand whether it’s free for all or not.