callout box with publii + markdown

Ok, so here are the results. As a noob, I thought callout box were standards. It appears that it is not. I checked in the CSS of the Simple theme V2.2.0.0, I did not find something that refers to callout box or alert. So if anyone wants to achieve callout box, here is a solution :
In Publii>Tools>Custom CSS, you add the following code, courtesy of Bootstrap :
.alert { position: relative; padding: 0.75rem 1.25rem; margin-bottom: 1rem; border: 1px solid transparent; border-radius: 0.25rem; } .alert-heading { color: inherit; } .alert-link { font-weight: 700; } .alert-dismissible { padding-right: 4rem; } .alert-dismissible .close { position: absolute; top: 0; right: 0; padding: 0.75rem 1.25rem; color: inherit; } .alert-primary { color: #004085; background-color: #cce5ff; border-color: #b8daff; } .alert-primary hr { border-top-color: #9fcdff; } .alert-primary .alert-link { color: #002752; } .alert-secondary { color: #383d41; background-color: #e2e3e5; border-color: #d6d8db; } .alert-secondary hr { border-top-color: #c8cbcf; } .alert-secondary .alert-link { color: #202326; } .alert-success { color: #155724; background-color: #d4edda; border-color: #c3e6cb; } .alert-success hr { border-top-color: #b1dfbb; } .alert-success .alert-link { color: #0b2e13; } .alert-info { color: #0c5460; background-color: #d1ecf1; border-color: #bee5eb; } .alert-info hr { border-top-color: #abdde5; } .alert-info .alert-link { color: #062c33; } .alert-warning { color: #856404; background-color: #fff3cd; border-color: #ffeeba; } .alert-warning hr { border-top-color: #ffe8a1; } .alert-warning .alert-link { color: #533f03; } .alert-danger { color: #721c24; background-color: #f8d7da; border-color: #f5c6cb; } .alert-danger hr { border-top-color: #f1b0b7; } .alert-danger .alert-link { color: #491217; } .alert-light { color: #818182; background-color: #fefefe; border-color: #fdfdfe; } .alert-light hr { border-top-color: #ececf6; } .alert-light .alert-link { color: #686868; } .alert-dark { color: #1b1e21; background-color: #d6d8d9; border-color: #c6c8ca; } .alert-dark hr { border-top-color: #b9bbbe; } .alert-dark .alert-link { color: #040505; }
Now, if you want to insert a callout box, from the editor, you wrap your paragraph in a html tag, for example <p></p> with the desired callout box as a class. For example, if I want a blue-ish callout box arround my paragraph, I add in the editor :
<p class="alert alert-primary"> My paragraph </p>
and it works \o/.
If you want some other kind of callout box, here is the bootstrap callout box related documentation :
https://getbootstrap.com/docs/4.4/components/alerts/
Enjoy !