I have a question concerning styles for generic blocks in BEM (for instance .button) vs Media Queries.

The block in BEM (as documentation says) is supposed to have generic styles which will be applicable to all elements on site, let's say I have a ".button" block...

And my button will have reusable styles like:

.button {
    font-family:Verdana;
    padding:30px 20px;
}

The purpose of that generic button is so that if I were to make "another" button, say "welcome button" with different styles I can write modificator button--welcome which will only add additional styles to .button which at the end will look like this:

<button class="button button--welcome"> </button>

This is where Media Queries PROBLEM comes in. Padding defined in my generic .button can be different for different media queries (I am using border-box so padding are internal styles for .button). For instance padding for max-width:480px can be padding: 10px 5px; Does it mean that I should NOT include padding in my generic .button block because .button will no longer be generic? Or, I can do something like this (but I wonder whether it is valid BEM way):

.button {
     font-family:Verdana;
     @media and (max-width: 480px) {
     padding:10px 5px;}
     @media and (max-width: 780px) {
     padding:15px 10px;
     }
     @media and (max-width: 1200px) {
     padding:20px 15px;
     }
     @media and (min-width: 1201px) {
     padding:30px 20px;
     }
}

Also, I've seen some generic .button blocks with the following code:

.button {
  padding: 0.75em 1.25em;
  border-radius: 4px;
  background-color: green;
  color: white;
  font-size: 1em;
  line-height: 1.5em;
  transition: all 0.15s ease-in-out;
}

The issue of generic block styles vs media queries arises in the case of border width, line-height which can be different for different media queries.

I've seen the documentation about external geometry/positioning, but padding is not external geometry: https://en.bem.info/methodology/css/#external-geometry-and-positioning

My issue here is different.

What is your opinion on USING SMACSS STATE CLASSES FOR COMMON MODIFIERS as suggested in this article?

http://sugarenia.com/blog/bem-pitfalls-advice/

Sometimes people write "BEM", sometimes "BEM 101". It's obvious what "BEM" comes from. But what is the source of "101" in the name..? I am so curious :)

Before (attempting) to use BEM, I'd mark my forms up something like this:

<form> 

    <h3 class="title">Form Heading <small>(if small tag is added)</small></h3>
    <p>Short paragraph of text...</p>

    <div class="form-group">
        <label class="label">Username <em>*</em></label>
        <div class="form-controls">
            <input type="text" />
        </div>
    </div>
    <div class="form-group error">
        <label class="label">Email address <em>*</em></label>
        <div class="form-controls">
            <input type="text" />
        </div>
    </div>
    <div class="form-group">
        <label class="label">Label</label>
        <div class="form-controls">
            <input type="text"  placeholder="" />
        </div>
    </div>
    <div class="form-group">
        <label class="label">Label</label>
        <div class="form-controls">
            <label class="radio"><input type="radio" name="radio" checked="checked" /> Option One</label>
            <label class="radio"><input type="radio" name="radio" /> Option Two</label>
        </div>
    </div>

</form>

It seems, obvious to use form__group instead of form-group and form__controls instead of form-controls. Using elements like this, the form would NEED a class of form on it - otherwise it makes no sense? Seems a bit strange on a default element though, I've not used <ul class="list"> for example, just <ul class="list--bordered"> for example.

I've created some quick, updated mark-up below, would this be acceptable?

<form class="form"> 

    <h3 class="form__title">Form Heading <small>(if small tag is added)</small></h3>
    <p>Short paragraph of text...</p>

    <div class="form__group">
        <label class="form__group-title">Username <em>*</em></label>
        <div class="form__controls">
            <input type="text" />
        </div>
    </div>
    <div class="form__group error">
        <label class="form__group-title">Email address <em>*</em></label>
        <div class="form__controls">
            <input type="text" />
        </div>
    </div>
    <div class="form__group">
        <label class="form__group-title">Label</label>
        <div class="form__controls">
            <input type="text"  placeholder="" />
        </div>
    </div>
    <div class="form__group">
        <label class="form__group-title">Label</label>
        <div class="form__controls">
            <label class="form__radio"><input type="radio" name="radio" checked="checked" /> Option One</label>
            <label class="form__radio"><input type="radio" name="radio" /> Option Two</label>
        </div>
    </div>

</form>

Thanks again!

Hi there,

I know one of the benefits of BEM is not having to nest styles but I was wondering when is it ok to do so? Sometimes it's unavoidable and sometimes maybe more practical to do so?

In the example I'm working on I have bands/stripes than contain blocks of content, these bands can be different colours (black, white, blue). I achieve this by having a base class of <div class="band">, which the band is black the following class is added: <div class="band band--black">. For obvious readability issues the content of a darker block will need to be coloured differently, the headings white, paragraphs/lists a lighter grey and maybe even a subtle lightening of the anchor colour. It'd be a pain to apply classes to everything, especially if different content mark-up appears on different pages. So is it acceptable to write the CSS like this (using SCSS):

.band--black {
    h1,
    h2,
    h3,
    h4 {
        color: rgb(255,255,255);
    }

    p,
    ul,
    ol {
        color: color: rgb(200,200,200);
    }
}

or even this, which might be able to keep track of, keeping the colour changes grouped together:

h1,
h2,
h3,
h4 {
    .band--dark & {
        color: rgb(255,255,255);
    }
}

p,
ul,
ol {
    .band--dark & {
        color: rgb(200,200,200);
    }
}

This is some (basic) sample HTML:

<div class="band band--dark masthead">
        <div class="wrap">

        <h1 class="masthead__title">Page heading</h1>
        <ul class="breadcrumbs">
            <li class="breadcrumbs__item"><a href="#" class="breadcrumbs__link" title="TITLE">Home</a></li>
            <li class="breadcrumbs__item"><a href="#" class="breadcrumbs__link" title="TITLE">Section Name</a></li>
        </ul>

        <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut volutpat accumsan purus, in posuere nibh aliquam faucibus. Nam varius lectus id nunc ullamcorper, at euismod enim placerat.</p>

        <h3>Related Categories</h3>
        <ul>
            <li><a href="#" title="TITLE TEXT">Category 1</a></li>
            <li><a href="#" title="TITLE TEXT">Category 2</a></li>
            <li><a href="#" title="TITLE TEXT">Category 3</a></li>
            <li><a href="#" title="TITLE TEXT">Category 4</a></li>
        </ul>

    </div>
</div>

Another question I have is the class of masthead, part of me thinks this should really be band--masthead following the BEM spec?

Thanks in advance, just starting off with BEM so I keep find myself questioning most of my implementations of it!