diff --git a/src/pretty-dom.js b/src/pretty-dom.js
index f4382bcd..14c5f772 100644
--- a/src/pretty-dom.js
+++ b/src/pretty-dom.js
@@ -7,7 +7,7 @@ import {getConfig} from './config'
 const shouldHighlight = () => {
   // Try to safely parse env COLORS: We will default behavior if any step fails.
   try {
-    const colors = process?.env?.COLORS
+    const colors = typeof process !== 'undefined' ? process?.env?.COLORS : undefined
     if (colors) {
       const b = JSON.parse(colors)
       if (typeof b === 'boolean') return b
@@ -18,7 +18,7 @@ const shouldHighlight = () => {
 
   // In all other cases, whether COLORS was a weird type, or the attempt threw:
   // Fall back to colorizing if we are running in node.
-  return !!process?.versions?.node
+  return typeof process !== 'undefined' && !!process.versions?.node
 }
 
 const {DOMCollection} = prettyFormat.plugins