In React, inline styles are not specified as a string. Instead they are specified with an object whose key is the camelCased version of the style name, and whose value is the style's value, usually a string ([more on that later](/react/tips/style-props-value-px.html)):
Style keys are camelCased in order to be consistent with accessing the properties on DOM nodes from JS (e.g. `node.style.backgroundImage`). Vendor prefixes [other than `ms`](http://www.andismith.com/blog/2012/02/modernizr-prefixed/) should begin with a capital letter. This is why `WebkitTransition` has an uppercase "W".