Header text on mobile

My site looks terrible on mobile. Any help appreciated – http://conference2016.daw.dementiascotland.org/

Hi,

I think there is missing css code on your site, did you ever change it?
There should be css code below for the header on mobile text:

@media only screen and (max-width: 499px){
  .main-navigation {
    padding-top: 15px;
  }

  .site-header.active-slider .site-branding {
    padding-top: 20px;
  }
}

No - have not changed it. Should I copy this code in?

please to implement the code above, you can put it using custom css plugin or in your child theme