main.css

A repository for the development of the HTML5 Boilerplate CSS file, style.css.

Historically, the file shipped with HTML5 Boilerplate was called main.css, hence the name of this project. It's since been renamed to style.css. Just in case you were confused.

This project includes both the whole main.css file as well as component files used to generate main.css. This way you can either pull in the whole file, as we do in HTML5 Boilerplate (renaming it to style.css) or you can pull in the individual files as needed.

Quick start

Choose one of the following options:

• Download as part of the latest stable release of HTML5 Boilerplate from html5boilerplate.com.
• Clone the git repo — git clone https://github.com/h5bp/main.css.git - and checkout the tagged release you'd like to use.
• Install with npm: npm install main.css and pull in what you need from the resulting node_modules/main.css/distfolder
• Install with yarn: yarn add main.css and pull in what you need from the resulting node_modules/main.css/distfolder

Features

The project contains the following files, which combine to create the different sections of main.css.

_base.css

Several base styles are included. These styles:

• provide basic typography settings that improve text readability
• protect against unwanted text-shadow during text highlighting
• tweak the default alignment of some elements (e.g.: img, video, fieldset, textarea)

_helpers.css

Along with the base styles, we also provide some commonly used helper classes.

.hidden

The hidden class can be added to any element that you want to hide visually and from screen readers. It could be an element that will be populated and displayed later, or an element you will hide with JavaScript.

.visually-hidden

The visually-hidden class can be added to any element that you want to hide visually, while still have its content accessible to screen readers.

.invisible

The invisible class can be added to any element that you want to hide visually and from screen readers, but without affecting the layout.

As opposed to the hidden class that effectively removes the element from the layout, the invisible class will simply make the element invisible while keeping it in the flow and not affecting the positioning of the surrounding content.

.clearfix

The clearfix class can be added to any element to ensure that it always fully contains its floated children.

Over the years there have been many variants of the clearfix hack, but currently, we use the micro clearfix.

_mqs.css

We include placeholder media queries to help you build up your mobile styles for wider viewports and high-resolution displays. It's recommended that you adapt these media queries based on the content of your site rather than mirroring the fixed dimensions of specific devices.

If you do not want to take the mobile first approach, you can simply edit or remove these placeholder media queries. One possibility would be to work from wide viewports down, and use max-width media queries instead (e.g.: @media only screen and (max-width: 480px)).

_print.css

Lastly, we provide some useful print styles that will optimize the printing process, as well as make the printed pages easier to read.

At printing time, these styles will:

• strip all background colors, change the font color to black, and remove the text-shadow — done in order to help save printer ink and speed up the printing process

• underline and expand links to include the URL — done in order to allow users to know where to refer to
  (exceptions to this are: the links that are fragment identifiers, or use the javascript: pseudo protocol)

• expand abbreviations to include the full description — done in order to allow users to know what the abbreviations stands for

• provide instructions on how browsers should break the content into pages and on orphans/widows, namely, we instruct supporting browsers that they should:

  • prevent block quotations, preformatted text, images and table rows from being split onto two different pages
  • ensure that headings never appear on a different page than the text they are associated with
  • ensure that orphans and widows do not appear on printed pages

The print styles are included along with the other css to avoid the additional HTTP request. Also, they should always be included last, so that the other styles can be overwritten.

Browser support

We use the default browserslist configuration which translates to this full list of browsers.

Contributing

Anyone is welcome to contribute, however, if you decide to get involved, please take a moment to review the guidelines:

• Bug reports
• Feature requests
• Pull requests

License

The code is available under the MIT license.