Customize 'Read More' button text on slider for Wordpress theme

I'm building a site using Wordpress and wanted to change the text in the slider buttons. The text says 'Read More' and since this is a Spanish site, I wanted to translate it. I'm a newbie in Wordpress and was surprised this wasn't something configurable in the theme or general site settings. Most of the solutions I found googling required to add a custom php function to override the text.

At the end I found you can add custom css in the theme. So I used a css trick to change the content. First one hides the element and then uses the after selector in combination with the content css element.

.featured-link a span {
  display: none;
}
.featured-link a:after {
  content: 'Leer';
}