Just add remove_button_css as class to your button tag. You can verify the code for Link 1
.remove_button_css {
outline: none;
padding: 5px;
border: 0px;
box-sizing: none;
background-color: transparent;
}
Extra Styles Edit
Add color: #337ab7;
and :hover
and :focus
to match OOTB (bootstrap3)
.remove_button_css:focus,
.remove_button_css:hover {
color: #23527c;
text-decoration: underline;
}