Change Size of Image on Welcome Page

Hey everyone, 

I just created a survey. On the Welcome page I added my title, a subtitle and an image. Originally I wanted to insert the image below the subtitle, but this is not possible given the layouts (is there a way to insert the image below?). It looks very good on the preview. However, when I navigate to the "real" questionnaire, the image is much bigger than the text next to it, even though I have set the text to Large. Even if I reduce the size of the inserted image, the image is still the same size (apparently it adjusts automatically. How can I reduce the image so that it is not so big compared to the text? Thanks for any help.