Can't apply CSS for Drop Shadows to a single page, it's only showing up if added to the full website CSS edits, how do I get it to work on the single page?

I have this custom code for Drop Shadows: .image-block {filter: drop-shadow(5px 5px 8px #d3d3d3);}

It works for the entire site when applied as a custom CSS in the Website Tools, however I only want it applied on a single page. When adding to the Advance custom CSS for the specific page, the effect does not show up.

@jaeveedee Thank you! That worked. I was hoping to add it to just that page, so I didn't have to worry about it showing up on future pages my client adds. Amazing it's just adding the <style> to it on a specific page. Just curious, if there's an easy explanation as to why it's different at the page level, vs the whole site level of code? Really appreciate the help. 

@TaeReid It's not any different than any code injection area in your site. The Custom CSS panel however is a LESS preprocessor so you just write up your css in there and SS does the work to translate into regular CSS and minify. I honestly wouldn't use the page header code injection with style tags as the way to do this as a best practice if you're giving it to a client. Finding the page collection id and adding it to CSS makes it so that if someone else ever takes over managing or customizing the site they don't have to go tracking down your code. Everything is within that custom css panel and easy to find.

@jaeveedee Okay, that's good to know. I'm not sure if she'll be updated ONLY this page so keeping it on the page might be best for her. If I was to add this to the overall Website Tool CSS section, what would the code look like for adding the drop shadow to only that Page (assuming I have the page ID and located that) could you share a code with a hypothetical page id in place?

It would look basically the same without the style tags

#collection-XXXXXXXXXXXX .image-block {
  filter: drop-shadow(5px 5px 8px #d3d3d3);
}