Changing "Normal" font size in one text block

Site URL: https://www.cindyolnick.com/about

Hi all -- Can I make the organization names under "Memberships" a bit smaller on this page without changing the rest of the body text? If so, how? Many thanks for your help!

Best,

Cindy

Add to Home > Design > Custom CSS

div#block-yui_3_17_2_1_1589588579389_33663 p {
    font-size: 15px;
}