How can we change the back ground

Answer 1

can you put code here please so i can look at it and see what you are talking about

Answer 2

1. Don't put HTML codes in CSS tab.

2. Don't use local storage for src of img. Upload to a web image host.

[Tutorial] Upload content from your device to CodePlayground - The Dropbox way
https://code.sololearn.com/WW6t4B73kJVz/?ref=app

3. In case above is too long :

3.1 Visit dropbox for websites
3.2 Create account with an email
3.3 Upload image
3.4 Get full web address of your image (starts with http)
3.5 Edit the ending of the address based on the instructions in abive tutorial by Mickel.
3.6 Copy in the src of img tag.