Links in the tour tip body are visually the same as the rest of the text

Problem/Motivation

Seven's CSS is written in a way that makes the links in the tip body indistinguishable from the rest of the text:

"I'll teach you more about paragraphs" part is the the link. As the image clearly shows it is almost impossible to notice (unless one hovers it accidentally).

Proposed resolution

1. Make the links in the tip body blue as Seven does in the other cases:
   
   The colour should provide contrast of 4.5:1 against the tour tip background to satisfy WCAG 2.0 success criterion 1.4.3 Contrast (minimum).
2. Underline the links inside tour tip paragraphs, to satisfy WCAG 2.0 success criterion 1.4.1 Use of color, and avoid F73: Failure of Success Criterion 1.4.1 due to creating links that are not visually evident without color vision.

Steps to reproduce

1. Enable Language module
2. Visit /admin/config/regional/language/add
3. Click Tour in the upper right hand corner
4. Navigate to the third Tour item. This item has a link.