The logo image is too large and if I remember that 3.x style correctly the max header size w/o it disrupting the appearance would be 165px (height). Give that a try and see if uploading a smaller images sorts the header issue. Now in some older 3.x style you could easily use header variables in the navbar and vice-versa, not true in 4.x as you must register the variable but the point I'm making is, check to see if you need to edit the Header or Navbar template. I just redid that for 4.x but so much work since then I honestly forgot however a good few tips just now so check them out

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