Removing underline on drop down navigation - desktop and mobile

Site URL: https://lobster-ray-g42d.squarespace.com/config/design/custom-css

Hi - I am hoping someone can assist. I am struggling to remove the underline in my dropdown navigation and mobile navigation. I have been using the following codes, which have been suggested in previous queries, but it does not seem to work for me and I don't know why!

Thank you!

header a {
  background-image: none !important;
}

div.header-menu-nav-item--active a {
  background-image: none !important
}

.header-nav-wrapper a {
    background-image: none !important;
}

Try this code

div.header-nav-item * {
	background-image: none !important;
}

25 minutes ago, tuanphan said:

Try this code

div.header-nav-item * {
	background-image: none !important;
}

 

YES!! Thank you, that worked. Much appreciated