style(www): remove margin on code-example

[jdegand]

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PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[ ] Feature
[X] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Header margin issue.

Closes #4876

What is the new behavior?

I think it looks better without any margin between the code example and header. Header already has enough padding.

Does this PR introduce a breaking change?

[ ] Yes
[X] No

Other information

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[jdegand]

On line 30

      .body {
        padding: 0 0px;
      }

There is a missing px in the padding rule. I've noticed a lot of 0px declarations in the styling. This serves no purpose outside of --var and calc and I'd suggest a find and replace to just use 0. Or you can keep it.

[jdegand]

Also, standalone:true is in this component as well. There are likely quite a few of these that can be removed.

[timdeschryver]

We have to keep the margin in some cases, otherwise the code is "too attached" to the text above it.

Previously:

[jdegand]

Hard-coding margin makes the component inflexible. Maybe, it is better to add an input for margin styling. If you add just margin-top: 8px to the component, you'll likely have a situation where a double margin is created somewhere. You could place a class on the app-code-example component and use that to handle margins.

[timdeschryver]

I noticed that this isn't related to the css.
Some code blocks are fine, while other are not.
The reason is the formatting in the docs.

If the code example component goes over multiple lines, the content is not added as the body, but as a separate tag under the component.

<ngrx-code-example header="src/app/app.module.ts">

not fine:

<ngrx-code-example 
   header="src/app/app.module.ts">

Closing this PR and issue, I will go over the examples to fix it.

Thanks for looking into this @jdegand