cannot adjust drop down menu width

I have been attempting to modify the width of the drop down menu of a form i created in CF7. I have found several mentions all over the web but none of them seem to work. I was able to adjust the color, font, field height, etc by creating the code below:

.wpcf7 select
{ outline: none;
  font-size:16px;
  font-family:Arial, Helvetica, sans-serif;
  height: 30px;
  color: black;
  width: 50%;
  }

However, the width attribute does nothing to affect the size of the field. I have tried setting a size in px, and percent.

Am I using the correct attribute? Is there somewhere else I can edit this? Is is supposed to auto-size on the content? (which, still makes no sense because my content is 3 words or less and it spans the width of the site)

Can’t post link to site yet as i’m still doing heavy devving at the moment, but if absolutely necessary, I will.

http://wordpress.org/plugins/contact-form-7/