You can hide that ugly 'Choose File' button by putting it inside a hidden div, and then have a nice bootstrappy button in its place that relays the onclick even

You can hide that ugly 'Choose File' button by putting it inside a hidden div, and then have a nice bootstrappy button in its place that relays the onclick event to it via javascript. I only mention it, as I discovered how to do it (and auto upload) only a few days ago...