The second line is styled in the theme like this:
.banner-caption span {
display: block;
font-family: arial, helvetica, sans-serif;
font-style: normal;
font-size: 0.75rem;
text-transform: uppercase;
}
You can change any of those with your own custom CSS, using a plugin like Simple Custom CSS. The font used is Arial, but if that is not available, then it moves to the Helvetica, then if that isn’t available, the third option is sans-serif. So when you add your own font, you can do the custom CSS like this:
.banner-caption span {
font-family: "your font", arial, helvetica, sans-serif;
}
If you want to change the other attributes like font style, font-size, etc., just add them to your custom CSS.
Font management is a very involved part of any website because there are so many variations. If you want to use a font from Google fonts that does not exist on everyone’s computers, you will want to check out the Easy Google font plugin.
To change the font for the main title part of the caption box, you can do this custom CSS:
.banner-caption {
font-family: "your font",arial,helvetica,sans-serif;
}