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<html><head><script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script><script>$(document).ready(function(){ $(":file").css("background-color", "red");});</script></head><body><form action=""> Name: <input type="text" name="user"><br> File: <input type="file" name="myfile"></form></body></html>