CSS: How to hide Contact Form 7 text labels

An example Contact Form 7 form is here.

How do I hide the:

• Name (required)
• Email (required)
• Phone (required)

I have tried:

.wpcf7-form p label {display: none;}
.wpcf7-form p label span.wpcf7-form-control-wrap {display: block;}

but this didn't work.

Help appreciated.

Why don't you remove them in WordPress backed?