Your LimeSurvey version:  LimeSurvey Community Edition   Version 5.3.12+220502
Own server or LimeSurvey hosting: Own server
Survey theme/template: Fruity
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Hello All,
My survey currently has a lot of text and pictures in the welcome and end message and I have changed the source code of the welcome message so that the entire text in centered to suit the background image of the tool. However the changes aren't getting nicely translated into the mobile version/layout of the tool. Could anyone suggest a workaround or a solution ?
Thank you:)
     

You are aware that LimeSurvey is bootstrap 3.4.1 based?
There is no class ".card", or did you define one?

And only seeing these thre lines we can't decide if your design is really responsive. (obviously not).
I do not see any ".rows" or ".columns", what you expect in a responsive layout.

So you should provide a bit more.

Joffm

Given the extremely wide layout, I can guarantee that you will never get it to look proper on mobile devices. Consider a completely different layout for mobile.