You can change the font sizes, if you prefer them larger or smaller than the theme defaults.
In WordPress, go to Appearance > Customize > Additional CSS
Add the following CSS for changing the most common elements - body font, title/heading fonts, menu fonts.
The theme sizes are listed below, so you can make the font-size for each of them larger or smaller, accordingly.
/* Theme Font Sizes */
body {
font-size: 18px;
}
h1,
.entry-title {
font-size: 42px;
}
h2 {
font-size: 36px;
}
h3 {
font-size: 32px;
}
h4 {
font-size: 28px;
}
h5,
.widget-title {
font-size: 24px;
}
h6 {
font-size: 18px;
}
.genesis-nav-menu a {
font-size: 15px;
}
.message-bar p {
font-size: 12px;
}
/* End Theme Font Sizes */