dotfiles/.config/gtk-3.0/widgets/button.css

/* buttons, also headings from table views like thunar
 */

button,
switch slider {
    background: @bg_color;
    color: @fg_color;

    border-radius: 0px;
    padding: 0.5em;
    border-width: 0px;
    border-color: transparent;
}

combobox {
    border-color: #00ff00;
    color: #ff0000;
    box-shadow: #0000ff;
}
button.flat {
    background: none;
    border-color: transparent;
}

button:hover,
button:focus
switch:hover slider,
switch:focus slider {
    color: @bg_color;
    background-color: @acc1_color;
}

button:backdrop,
button:disabled,
switch:backdrop slider,
switch:disabled slider {
    background: @bg_color;
}