diff --git a/utils/utils.typ b/utils/utils.typ
index 880359f..510978e 100644
--- a/utils/utils.typ
+++ b/utils/utils.typ
@@ -133,6 +133,8 @@
   style(styles => {
     let content-size = measure(content, styles)
     let content-width = content-size.width
+    // Convert percent/em into concrete units
+    let width = measure(h(width), styles).width
     if width < content-width {
       let ratio = width / content-width * 100%
       // The first box keeps content from prematurely wrapping