How can I make sure that my Selector does not overlap my text-area box when hover ? I would like for the selector to smoothly push down the text-area

Question

(https://i.stack.imgur.com/VaWfd.jpg) The selector overlaps the text-area

I would like for the selector to push down the text-area box smoothly when it is hovered over. The Selector just over laps the text area which is what I don't want I would love for the selector to act as a block and smoothly push down the elements below it.