Remove arrow in the navigation bar with submenu

I am using inkblot and I have four questions concerning the submenu.

1) I have inserted a submenu on my webpage. Unfortunately an arrow appears when I am using a submenu (see https://www.rita-limacher.ch, arrow next to “KONTAKT”…).
How can I remove this arrow?

2) Also, the border of the submenu is blurred. Where can I change that?

3) The text of the submenu is not left-aligned and it is therefore not within the background. Where can I change that?

4) Where can I change the color of the submenu?

Thank you very much for your help!