article preview using js with flexbox and grid

Hello, I tried to do the best I could so that's the result. Problems :

• I didn't succeed to make the share image white, I don't know how to change the colour of an image.
• I don't know why, but my media queries output displays page that is bigger than the screen
• I couldn't do the active form for the mobile preview when we click on the button.

If you can help me, please tell me. If you have any advices, please tell me too, thanks.