Samsung tablet, strange screen, only with thaivisa

[Golden Triangle]

I have a Samsung tablet, I was prompted to update security and now have a very strange setup on my thaivisa account, I went from controlled to severe and now the screen on thaivisa is black background, with yellow & green script, how do I get back to normal ? 

[OneMoreFarang]

Who prompted you to update the security of what?

What did you do to "update the security"?

[katana]

What browser are you using? May be some some kind of night time viewing mode has been selected..

[CharlieH]

As mentioned, that format looks like a browser setting, not the device.