woohoogle on "[Plugin: Contact Form 7] Button Styling Advice"

In fact the send button is not working on either approach.

This is the page in question:
http://www.elizeamornette.com/contact

I have tried both of these approaches within the contact form editor:

<p>[submit class:submit_button "Send Message"]</p>
<p><input class="submit_button" type="submit" value="Send Message" /></p>

I have also tried adding to my theme css AND/OR the plugin css as follows:

.submit_button{ padding:8px 10px 8px 10px; border-radius:5px; background-color:#000000; float:left; font-family:Verdana, Arial, Helvetica, sans-serif; color:#fff; border:none; cursor:pointer;}
.submit_button:hover{font-family:Verdana, Arial, Helvetica, sans-serif; color:#FF9900;}

Please help: I need to get the form to work and the styling to take effect