Comment by skydhash

4 hours ago

> There was no way to tell where a given style is used from, or even if it's used at all

It's pretty easy. Open the inspector, select an element and you will find all the styles that apply. If you didn't try to be fancy and use weird build tools, you will also get the name of the file and the line number (and maybe navigation to the line itself). In Firefox, there's even a live editor for the selected element and the CSS file.

> if the DOM hierarchy changes then your styles all change randomly

Also styles are semantics like:

- The default appearance of links should be: ...

- All links in the article section should also be: ...

- The links inside a blockquote should also be: ...

- If a link has a class 'popup' it should be: ...

- The link identified as 'login' should be: ...

There's a section on MDN about how to ensure those rules are applied in the wanted order[1].

This way, your styles shouldn't need updates that often unless you change the semantics of your DOM.

[1]: https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Casc...

2 comments

skydhash

lmm 3 hours ago

> Open the inspector, select an element and you will find all the styles that apply.

That tells me which styles apply to an element. You also need the converse - find which elements a given style applies to - and there's no way to do that AFAIK. It's very hard to ever delete even completely unused styles, because there is no way to tell (in the general case) whether a given style is used at all.

> This way, your styles shouldn't need updates that often unless you change the semantics of your DOM.

In my experience the DOM doesn't have semantics, or to the extent that it does, they change all the time.

skydhash 3 hours ago
> You also need the converse - find which elements a given style applies to - and there's no way to do that AFAIK.
I've never needed to do this, because I pay attention to my DOM structure and from CSS selectors can figure where a style applies. But I've just checked and the search bar for Firefox Inspector supports css selectors.
> In my experience the DOM doesn't have semantics, or to the extent that it does, they change all the time.
The DOM semantics are those of a hyper linked documents|forms. Take a page and think about what each elements means and their relations to each order. They will form a hierarchy with some generic components replicated. The due to how CSS is applied, you go from generic to specific elements, using the semantic structure to do the targeting
As an example, the structure of HN's reply page is
page header logo + Title body comment_box upvote_button + comment_metadata comment_text textbox // reply text button // reply
This and the structure of the other pages will give you an insight on how to target the relevant elements.