Twenty ten child theme needs its parent theme

I think I have done everything necessary to create a child theme of the twenty ten theme.

/*
 Theme Name:     twenty ten child
 Theme URI:      https://fabrica-vitae.com
 Description:    Fabrica-vitae 2014
 Author:         Even the Neck
 Author URI:     https://eventheneck.org
 Template:       twentyten
 Version:        1.0.0
*/

@import url('../twentyten/style.css');
@import url('https://fonts.googleapis.com/css?family=Open+Sans');

But the child theme css doesn’t seem to be applied to the website. And I see this text on the theme menu of the wp-admin; “This child theme requires its parent theme, Twenty Ten.”

Could someone please look at the website below and figure out what is the problem? Many thanks in advance.

https://www.fabrica-vitae.com/wp/