Issue with interpreting this site

Hi  I am having trouble with the layout of the site being correctly interpreted by multiple bowsers , tested on two different machines . ( Edge , Firefox , Chrome all tested) the layout is all muddled . See attached . Is anyone else having this problem ? This happens when creating a thread or replying to a message

  bios mods.PNG (Size: 36.23 KB / Downloads: 1)

  bios mods2.PNG (Size: 22.89 KB / Downloads: 0)