Goran Spasojevic


HTML5 Boilerplate homepage | Documentation table of contents


The HTML5 Boilerplate starting CSS includes:

This starting CSS does not rely on the presence of conditional classnames, conditional style sheets, or Modernizr. It is ready to use whatever your development preferences happen to be.


Normalize.css is a modern, HTML5-ready alternative to CSS resets. It contains extensive inline documentation. Please refer to the Normalize.css project for more information.

HTML5 Boilerplate defaults

This project includes a handful of base styles that build upon Normalize.css. These include:

You are free to modify or add to these base styles as your project requires.

Common helpers


Add the .ir class to any element you are applying image-replacement to. When replacing an element’s content with an image, make sure to also set a specific background-image: url(pathtoimage.png);, width, and height so that your replacement image appears.


Add the .hidden class to any elements that you want to hide from all presentations, including screen readers. It could be an element that will be populated later with JavaScript or an element you will hide with JavaScript. Do not use this for SEO keyword stuffing. That is just not cool.


Add the .visuallyhidden class to hide text from browsers but make it available for screen readers. You can use this to hide text that is specific to screen readers but that other users should not see. About invisible content, Hiding content for accessibility, HTML5 Boilerplate issue/research.


Add the .invisible class to any element you want to hide without affecting layout. When you use display: none an element is effectively removed from the layout. But in some cases you want the element to simply be invisible while remaining in the flow and not affecting the positioning of surrounding content.


Adding .clearfix to an element will ensure that it always fully contains its floated children. There have been many variants of the clearfix hack over the years, and there are other hacks that can also help you to contain floated children, but the HTML5 Boilerplate currently uses the micro clearfix.

Media Queries

The boilerplate makes it easy to get started with a “Mobile First” and Responsive Web Design approach to development. But it’s worth remembering that there are no silver bullets.

We include a placeholder Media Queries to 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 a “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 MQs instead, e.g., @media only screen and (max-width: 480px).

Take a look into the Mobile Boilerplate for features that are useful when developing mobile wep apps.

Paged media styles