added some styling options

src/renderer.typ

@@ -1,7 +1,7 @@
 #import "@preview/cetz:0.2.2": canvas, draw
 
 #let X-SPACE = 2
-#let Y-SPACE = 30
+#let Y-SPACE = 20
 
 #let get-participants-i(participants) = {
   let pars-i = (:)
@@ -69,10 +69,18 @@
     if elmt.type == "seq" {
       let x1 = x-pos.at(pars-i.at(elmt.p1))
       let x2 = x-pos.at(pars-i.at(elmt.p2))
+      let style = (
+        mark: (end: "straight"),
+        stroke: (
+          dash: if elmt.dashed {"dashed"} else {"solid"},
+          paint: elmt.color
+        )
+      )
+
       draw.line(
         (x1, y),
         (x2, y),
-        mark: (end: "straight")
+        ..style
       )
       if elmt.comment != none {
         draw.content(