Hi,
to the best of my knowledge PHP does not offer a way to detect the user's screen resolution.
Are you using JavaScript for that "run a script on opening a page"? In that case you can just use window.getWidth() to get the maximum available size of the window. Then you can do an if condition to run that script only if the window's size is larger than a certain amount:if( window.getWidth() > 1000 ) {
// run the script
}
This way the script only runs when the window size is larger than 1000 pixels.