When then field focus icon changes color > contact form 7

Hello.

I’m racking my brain if you can help me.
I work a lot with the contact form 7, I love this plugin.
I always try to bring a beautiful look to my forms, but there’s something I could not do with the Contact Form 7: I want the icon changes color when the focus field.

My Code:

[text* your-name id:your-name class:style-form]
<span class="fa fa-user icon-style"></span>

I wish this to happen in CSS:
input[type='text']:focus + span.fa-user {color: red;}

Exemple:

<input type="text" id="your-name" class="style-form" placeholder="Your Name"]
<span class="fa fa-user icon-style"></span>

CSS Exemple:
input[type='text']:focus + span.fa-user {color: red;}

Please, help me! Thanks