Simple loading spinners animated with CSS. See demo.

SpinKit uses CSS animations to create smooth and easily customizable animations. The goal is not to offer a solution that works in every browser—if you're supporting browsers that haven't implemented the CSS animation property (e.g. IE9 and below), you'll want to detect support for the animation property, and implement a fallback (see below.)

Grab the HTML and CSS for a spinner and include it in your project. Note that a hidden spinner (opacity: 0, or visibility: hidden) will still animate. After hiding a spinner, it's recommended to remove it from the DOM, set display: none or pause the animation by setting animation-play-state: paused.

SpinKit can also be installed to your project with bower:

$ bower install spinkit

If you're using SCSS in your project then you can include just the styles for the spinners that you want by adding the following to your main file:

@import '../bower_components/spinkit/scss/spinners/1-rotating-plane',
        '../bower_components/spinkit/scss/spinners/3-wave';

There are some variables that can be overridden if you use SCSS. The defaults are listed in scss/_variables.scss.

An easy way to provide a fallback animation is to check for support for the animation property, and replace the spinner with a GIF if it's not supported.

function browserSupportsCSSProperty(propertyName) {
  var elm = document.createElement('div');
  propertyName = propertyName.toLowerCase();

  if (elm.style[propertyName] != undefined)
    return true;

  var propertyNameCapital = propertyName.charAt(0).toUpperCase() + propertyName.substr(1),
    domPrefixes = 'Webkit Moz ms O'.split(' ');

  for (var i = 0; i < domPrefixes.length; i++) {
    if (elm.style[domPrefixes[i] + propertyNameCapital] != undefined)
      return true;
  }

  return false;
}

Use it to check for animation support:

if (!browserSupportsCSSProperty('animation')) {
  // fallback…
}

If you're submitting a new animation, make sure that it looks identical in all browsers that support CSS animations.

The animation styles should be put in an SCSS file which you place in scss/spinners/. Carefully look at the existing spinners to make sure you follow the same conventions and that you list an example on top of the page exactly like the other spinners (we extract this when generating the HTML files). Don't use any browser prefixes as this will be added automatically to the generated CSS files by autoprefixer.

To generate the CSS and HTML files you need to have node.js installed on your system. After that you need to issue npm install from the SpinKit project directory to install gulp and other dependencies listed in package.json. After doing this you should be able to just call gulp build to generate the files. These files should be included in your pull requests.