Adding a code block into a SquareSpace Header.

Hi Squarespace community, 

I'm in the process of building a website for a Gym. They have a Mind and Body account that so far has been easy to integrate into the website. 

I need to add a link to their mind and body login/registration into my website header which will be present on all pages. Unfortunately it is not as straightforward as just adding a link, it needs to be imputed through the code:

<script src="https://widgets.mindbodyonline.com/javascripts/healcode.js" type="text/javascript"></script><healcode-widget data-version="0.2" data-link-class="loginRegister" data-site-id="30689" data-mb-site-id="31900" data-type="account-link" data-inner-html="Login | Register"  />

I have added a screen shot of the home page to clarrify what i'm after. Circled in red in 'login' thats where i need the mindbody code to be injected!

Any help on this would be greatly appreciated. 

Cheers

Emma 

Hi. Can you share your site url? We can help easier