diff --git a/src/lib/substituteVariantsAtRules.js b/src/lib/substituteVariantsAtRules.js
index 01d9885b8..2ae282846 100644
--- a/src/lib/substituteVariantsAtRules.js
+++ b/src/lib/substituteVariantsAtRules.js
@@ -79,7 +79,9 @@ export default function(config, { variantGenerators: pluginVariantGenerators })
 
       _.forEach(_.without(ensureIncludesDefault(variants), 'responsive'), variant => {
         if (!variantGenerators[variant]) {
-          throw new Error(`Your config mentions the "${variant}" variant, but "${variant}" doesn't appear to be a variant. Did you forget or misconfigure a plugin that supplies that variant?`);
+          throw new Error(
+            `Your config mentions the "${variant}" variant, but "${variant}" doesn't appear to be a variant. Did you forget or misconfigure a plugin that supplies that variant?`
+          )
         }
         variantGenerators[variant](atRule, config)
       })