Hyperlink not underlinked

Hello,

I want my hyperlinks to be underlined in my blog posts but they aren’t. I tried inputting custom CSS into the “Additional CSS” section and inputting:

a {
text-decoration: underline;
}

however, this makes ALL the links on my blog underlined, including the titles of my posts, the categories, even the name of my blog in my background photo. I dont want that. I only want the hyperlinks to be underlined in each blog post. Can anyone advise?

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