Effects of changing the screen size


when I change the screen size my header image and the main block moves according to screen size. Even for small screens the header image is out of the screen. Is there any idea to solve the problem ?


when I reduce the browser size the main block goes to under the left sidebar which is very annoying. any idea to solve the problem ?

and apparently the ClassicBlue theme (and also the other themes) makes the problem, however, the custom theme plugin works perfectly.

This is more of a CSS question than an OJS question. You can customize the CSS in Journal Setup, Step 5.6 “The Look”: “Journal Layout”
User Home → Journal Manager → Setup → 5. The Look → 5.6 Journal Layout

For some excellent CSS tutorials, I recommend w3schools.