Yes, you can.
The button’s current look and feel is given by class="glf-button". In this class we have defined the properties that make it look orange, have the font white and so on. So you can change the button style in two ways:
Here are some properties you can use inside the style attribute:
Background-color - Sets the button color.
Color - Sets the text color. Make sure you add "!important" for this to work.
Font-size - Sets the font size
Padding - Sets the space around the text.
Border-radius - Sets the shape of the border. The higher the value, the more rounded the corners.