How to center and enlarge an embedded 3D model?

Would anyone be able to provide the code to make this embedded model full screen and central as opposed to tiny and sat to the left? (Password to store is just ‘Password’.

https://www.tailormadedesigns.co.uk/pages/3d-model

Embed code is:

Add this code to the section “CSS Custom” of your theme editor:

.sketchfab-embed-wrapper iframe{
width:100%;
height:800px;
}

I can’t find this in the dawn theme. Would it be under Base CSS?

Just added it to Base CSS and worked perfectly. Thank you.

Not in the Theme code editor, just in the theme customizer on the side panel

Hi @tailormade1

This is Richard from PageFly - Shopify Page Builder App, I’d like to suggest this idea:
Online Store ->Theme ->Edit code
Assets ->Base.css

.sketchfab-embed-wrapper iframe{
   width:100% !important;
   height:800px !important;
}

Hope you find my answer helpful!
Best regards,
Richard | PageFly