Update README.md to reflect latest poole.css.

diff --git a/README.md b/README.md
index c0bff196000f09ff0bc5b8bf4c93850ef9c4ccc3..e11acd9da15222ed61c62bbec9b2b9231698d0ed 100644 (file)
--- a/README.md
+++ b/README.md
@@ -77,7 +77,7 @@ html {
   font-size: 16px;
   line-height: 1.5;
 }
-@media (min-width: 38rem) {
+@media (min-width: 38em) {
   html {
     font-size: 20px;
   }