Custom CSS not applyng to Woocommerce sites

Hi, I am having trouble applying custom CSS to the specific part of the Woocommerce site.

My code is:

.single. single-product .postid-5474 #details.component_data
{
color: #fff !important;
}

I would like the part with the product description to change color (from gray to white). I had tried everything and the code doesn’t want to apply. I had noticed that I can’t add any custom changes to the Woocommerce sites, while custom css works normally on other pages. I am not an experienced web-developer, so I am looking for a step-by-step explanation of what is going on an how to fix it. I am using the Divi theme.

Thanks in advance!

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