header image not showing in mobile device | uploaded media but not visible

Hello Support,

1. I am not able to see my header image in my mobile or tab. I am able to see in desktop mode. Pleas help me out what should I do so that the image is responsive and can be seen same on all device, I have already tried the responses given earlier but that was not working, and I don’t know how to use this through Additional CSl.

2. I have uploaded media files in my poste but they are not visible in the main website, I have tried all the things and its showing attached in the backend but when I do check my website, its just shows blank. Please help me with these two problems

The page I need help with: [log in to see the link]