Change textarea size with contact form 7

This is my first experience ever in WordPress so please be gentle. Creating a website to generate sales leads. Using a form on each page to gather info and email on last form. Works good except I need to resize the textarea boxes. For instance, the zip code box is 10 times the size it needs to be. I was able to successfully resize with [textarea* zip code 10/10] but the form doesn’t recognize the box to email it. I tried using [textarea-23* zip code 10/10] but the box then just lists the actual text inside the brackets. I have several text boxes that need their own size or I would do a resize in the css. Any and all help appreciated.