Theme development

How to add an ID selector to Stylesheet?!

Stylesheets are added through .info file....

or is there another way?!

I am researching the ways to switch themes by user, the ID would help a lot...

Drupal 7

Hi.

I have been using Joomla for years and also made few themes for it. But now since 3.X is long in the tooth and J4 is not stable enough (esp for Chromium based browsers) yet I have decided to convert to Drupal.

I have to say I am so far blown away how awesome Drupal is!

Now, I am building a simple shop website for my software and games. I would like the website to have esthetics of Battle.net with possibly implementing a nav menu similar to that on gog.com.

Hello,
I am on Drupal 9.1.9, trying to display node-content of pages through the "printable" module (printable/printable_pdf both at v 2.0.1). I use a subtheme of bartik.
The print widget is defined to be displayed in the content area. Using css, I actually want to position it on the right edge of the breadcrumbs region. 

How can I prepare specific file name suggestion and override a view page template? I tried all followed ways but not change and only renders <!-- BEGIN OUTPUT from 'core/themes/stable/templates/views/views-view.html.twig' -->

I have custom node-form.html.twig templates for all my content-types for heavy customisation. I was trying to improve the file structure but for some reason, the node-form templates only work if I put them in the root of the templates folder. If I move them in a subfolder (/templates/node-forms for example) I'm getting an error:

Twig\Error\LoaderError: Template "themes/mytheme/templates/node-form.html.twig" is not defined.

Do I have to specify anything more in my theming function below to make Drupal aware of the sub-location?

I get SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: nodename nor servname provided, or not known error during cache-rebuild so checked Connection.php and saw the $dsn value is different with .env and settings.php info. according to followed var_dump it returns string(58) "mysql:host=server1;port=3306;charset=utf8mb4;dbname=testdb"