App Showing Wrong Resolution When Deployed To AWS Amplify

I created a web app using React. After I deployed it to AWS Amplify, I found that the deployed app had a lower resolution than my test version in the local environment. (Everything in the deployed one appears larger than normal.) What could cause this inconsistency?

Please let me know if you need more details. This is the first question I've asked in StackOverflow. Thank you in advance!