JSS
An authoring tool for CSS which uses JavaScript as a host language
... on CodeSandbox. JSS generates actual CSS, not Inline Styles. It supports every existing CSS feature. CSS rules are created once and reused across the elements using its class name in contrary to Inline Styles. Also, when DOM elements get updated, previously created CSS rules are applied. JSS generates unique class names by default. It allows avoiding the typical CSS problem, where everything is global by default. It completely removes the need for naming conventions.