Shifting Tagline beneath Logo

Depends on your expertise. You can tweak the php, but CSS is the easier option.

Give us a link and maybe we can resolve it.

You don’t seem to have a Tagline to move. Using one of my test sites, I can move my Tagline using:

.span7.inside.site-description {
  float: none;
  margin: 0 0 0 -110%;
  width: 100%;
}

But there needs to be some @media adjustments on different viewports for a Responsive solution.