How to change color of tabs border in Safari and other browsers?

I have put the ion-tabs into my project, below the ion-content on individual pages.

Now I want to change the border-top color. I tried the following, but this does not work on neither Chrome or on Safari (I get a double border: the native one and mine). On Chrome there is nothing and on Safari you still see the native colour.

.tabs {
  border-top: 1px solid;
  border-color: #00D7FF !important;
  background-color: rgba(255,255,255,1) !important; /* or transparent, or background:none */
  /*background-color: #fff !important; */
}