split up sources into manageable files

src/util.typ

@@ -0,0 +1,40 @@
+#let colors = (
+  orange: rgb(245, 180, 147),
+  yellow: rgb(250, 225, 127),
+  green: rgb(127, 200, 172),
+  pink: rgb(236, 127, 178),
+  purple: rgb(189, 151, 255)
+)
+
+#let lpad(s, len) = {
+  let res = "0" * len + s
+  return res.slice(-len)
+}
+
+#let opposite-anchor(anchor) = {
+  return (
+    north: "south",
+    east: "west",
+    south: "north",
+    west: "east",
+
+    north-west: "south-east",
+    north-east: "south-west",
+    south-east: "north-west",
+    south-west: "north-east"
+  ).at(anchor)
+}
+
+#let rotate-anchor(anchor) = {
+  return (
+    north: "east",
+    east: "south",
+    south: "west",
+    west: "north",
+
+    north-west: "north-east",
+    north-east: "south-east",
+    south-east: "south-west",
+    south-west: "north-west"
+  ).at(anchor)
+}