diff --git a/lib/src/property.dart b/lib/src/property.dart
index 69f5c54..a2f4f6e 100644
--- a/lib/src/property.dart
+++ b/lib/src/property.dart
@@ -823,10 +823,12 @@
   String get cssExpression {
     return (top == left && bottom == right && top == right)
         ? "${left}px"
-        : "${top != null ? '$top' : '0'}px ${
-      right != null ? '$right' : '0'}px ${
-      bottom != null ? '$bottom' : '0'}px ${
-      left != null ? '$left' : '0'}px";
+        : "${top != null ? '$top' : '0'}px ${right != null
+            ? '$right'
+            : '0'}px ${bottom != null ? '$bottom' : '0'}px ${left !=
+                null
+            ? '$left'
+            : '0'}px";
   }
 }