Changing link color in footer as it fixes #2015

[Aashaan403]

Changes

The color of the hyperlinks when hovered is changed to the orange (This orange is not actually orange in light theme as it is defined two color values in the assets/sass/dark-mode.css.

Context

This helps in better visibility as the previous color for the link hovering almost blended with the background This was discussed with @dscho in issue #2015