User agent redirect to transition page - load target web page images in transition page - redirect to target page

Hello, I would like to use the user agent function to detect human users. When any <a> tag is clicked, the JS code redirects to a transition webpage which i will design using animations. you will have to make sure the target webpage in the url of the <a> tag is included in the transitions webpage url as a query parameter. Then when the animations are running i need to transition page ot run JS to fetch all images from the target web page and load them in the background. once the images are loaded, then the transition page uses the parameters in the query of the url to goto that specific page. Thanks.