Use a namespace to increase the CSS specificity of your styled-components, preventing them from being overwritten by overly broad rules from the page’s stylesheets.

Add the plugin to your Babel configuration before the styled-components plugin, and specify a CSS selector as its namespace:

"plugins": [
  [
    "babel-plugin-namespace-styled-components",
    { "namespace": ".my-namespace" }
  ],
  "styled-components
]

Then render your app’s content within that namespace:

MyApp = () => <div className="my-namespace">{appContent}</div>;

Now all styled() blocks will emit selectors that use that namespace.

.bMqNs {
  color: tomato;
}

.my-namespace .bMqNs {
  color: tomato;
}

If you use multiple ampersands (&&) in a selector in a mixin (that is, a style block inserted into a styled() template with ${}), that selector will not match anything. This is a fundamental problem with namespacing at build time: styled-components resolves & to

.namespace .c0

which means that && will resolve to

.namespace .c0.namespace .c0

When the plugin detects an invalid selector like this in a styled-components css() block, it’ll throw an error at build time. Be careful to wrap mixins in css() rather than using raw strings, which are ignored by the plugin and therefore potentially unsafe.

Thanks to QuickBase’s babel-plugin-styled-components-css-namespace for inspiring this project!