diff --git a/sys/terminal.js b/sys/terminal.js
index 37f4d33..25a5e0b 100644
--- a/sys/terminal.js
+++ b/sys/terminal.js
@@ -108,7 +108,7 @@ function makeColorCodesPrintable(input) {
 function convertColorCodes(input) {
     return input.replace(/\$#([0-9a-fA-F]{6})/g, '<span style="color: #$1">')
                 .replace(/\$##([0-9a-fA-F]{6})/g, '$$#$1')
-                .replace(/\$([A-Z_]+)--/g, '<span style="color: --$1">')
+                .replace(/\$([A-Z_]+)--/g, '<span style="color: var(--$1)">')
                 .replace(/\$#([A-Z_]+)--/g, '$$$1--')
                 .replace(/\$reset/g, '</span>')
                 .replace(/\$#reset/g, '$$reset');