How to fix broken woocommerce quantity buttons

Question

I have a Wordpress site with a custom theme and Woocommerce installed. The problem I am having is that buttons to increase the quantity (+/-) are not working. When a quantity button is clicked, it doesn't change the quantity value and the button jumps to the left. I assume it must be a problem between the theme and Woocommerce as Woocommerce works flawlessly elsewhere.

Does anybody know how to fix the woocommerce quantity buttons so that they increase/decrease the quantity field.

Answer 1

In case anyone was interested, it turned out that some styling from the theme was applying the css: left:1px; when the quantity buttons has the pseudo-class :active. So when a quantity button was clicked, the button was being moved to the left without the onclick event firing.