bug #1541 Add a background color to the jumbotron on the homepage (rosier)

This PR was merged into the main branch.

Discussion
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Add a background color to the jumbotron on the homepage

Bootstrap dropped the jumbotron component

https://getbootstrap.com/docs/5.3/migration/#jumbotron

Commits
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f86d770 Add a background color to the jumbotron on the homepage

Author: javiereguiluz

assets/styles/app.scss

@@ -414,6 +414,7 @@ body#homepage .page-header a.language-selector-dropdown-button .current-language
   margin-inline: 5px 10px;
 }
 body#homepage .jumbotron {
+  background: var(--secondary-color);
   display: flex;
   flex-direction: column;
   height: 100%;