Change font size caption masonry gallery

Site URL: https://www.maartendelobel.com/

Hi, I want to change the fontsize of my captions underneath my pictures that's on a masonry gallery page. Squarespace doesn't support this, but may be somebody can provide me a CSS-code for it? Thank you.

Add to Home > Design > Custom CSS

/* gallery masonry caption */
.gallery-masonry-item p.gallery-caption-content {
    font-size: 10px;
}