Software development is a team effort
When doing software development it is essential to agree on guidelines, technology, and methodologies. Those agreements should be the result of discussions, proof of concepts, knowledge, and sometimes votes. The whole team should be invited to participate because software development is a team effort and everyone likes engaging team members.
At visuellverstehen, we are divided into multiple teams. Some teams agreed on using Block-Element-Modifier (BEM) and other teams agreed on using Tailwind CSS. I think it is super important to agree on one way or the other, while both ways are totally fine for the success of our client projects.
One thing is for sure. If you do not agree, it will become a mess. I have been there.
Learn proper BEM
Now and then new colleagues join our team. Some of them never have heard about BEM before. So they have to learn it and naturally some mistakes will happen. Mistakes are not a problem at all. They are part of the learning process.
Four most common mistakes
To help you learn proper BEM, I wrote down some of the most common mistakes I see in my day-to-day work life.
1. Wrongly nested blocks and elements
It is not allowed to nest blocks. If you start a new block, you are not allowed to proceed with elements from another block.
❌ Wrong
<article class="card">
<header class="header">
<h2 class="card__headline"></h2>
</header>
</article>
✅ Correct
<article class="card">
<header class="card__header">
<h2 class="card__headline"></h2>
</header>
</article>
2. Great-grandchildren
There are no grandchildren nor great-grandchildren in BEM. Instead, »normal« elements of the block can be used.
❌ Wrong
<article class="card">
<header class="card__header">
<h2 class="card__header__headline"></h2>
</header>
</article>
✅ Correct
<article class="card">
<header class="card__header">
<h2 class="card__headline"></h2>
</header>
</article>
3. Modifiers without a base class
Modifiers cannot exist without a base block or element.
❌ Wrong
<article class="card--highlight">
<header class="card__header"></header>
</article>
✅ Correct
<article class="card card--highlight">
<header class="card__header"></header>
</article>
❌ Wrong
<article class="card">
<header class="card__header--important"></header>
</article>
✅ Correct
<article class="card">
<header class="card__header card__header--important"></header>
</article>
4. Too big blocks
It is not a good idea to create really big blocks. The idea of BEM is to create modular and reusable blocks.
❌ Wrong
<body class="body">
<header class="body__header"></header>
<main class="body__main"></main>
<footer class="body__footer"></footer>
</body>
✅ Correct
<body class="body">
<header class="header"></header>
<main class="main"></main>
<footer class="footer"></footer>
</body>
Automate stuff
Sometimes it is hard to find mistakes manually. Yesterday I learned there is a BEM linter. I will look into it.
Top comments (19)
Thanks, I am learning BEM and this is helpful :)
Glad it helps :)
Simple and clean explanation. Thanks for this.
We are using BEM in our team. yes of course with these mistakes :) will correct these
Thanks for your feedback.
I didn't know the grandchildren one, thanks!
Awesome. You are welcome.
I've been using BEM for my home projects, I even tried to combine multiple conflicting resouces. Starting early in BEM after learning CSS is really helpful in improving your wider point of view of the project. Thank you for the tips🙂
Thanks for your feedback :)
I usually make mistakes 2, 3, 4 except 1.
Though there are just 4 mistakes, they're precious.
Thank u for your sharing.
Mistakes are part of the learning process. Keep on and happy coding :)
Very interesting...
who never made a couple of those mistakes?
I still do... :)
tx
Thanks for commenting. Everyone makes mistakes.
this tips are all correct and when using BEM with SCSS all of this will make sense. ;)
Thanks for your comment. I agree with you. In addition I think, BEM makes also sense with PostCSS, Less or Vanilla CSS.
Tip for the great-grandchildren 👍
Thanks for your feedback :)
I always did mistake number 2 which leads to messy structure, so thanks for clarification!
No one wants messy structure. Glad it helps. Have fun writing proper BEM.
Thank you :)