added max-width param to _col

src/diagram.typ

@@ -19,14 +19,15 @@
   ),)
 }
 
-#let _col(p1, p2, width: auto, margin: 0, min-width: 0) = {
+#let _col(p1, p2, width: auto, margin: 0, min-width: 0, max-width: none) = {
   return ((
     type: "col",
     p1: p1,
     p2: p2,
     width: width,
     margin: margin,
-    min-width: min-width
+    min-width: min-width,
+    max-width: max-width
   ),)
 }