diff --git a/src/components/drawing.tsx b/src/components/drawing.tsx
index 1cd9a36..e07e48e 100644
--- a/src/components/drawing.tsx
+++ b/src/components/drawing.tsx
@@ -1,10 +1,12 @@
-import React, { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import React, { useCallback, useEffect, useRef, useState } from "react";
 import { clsx } from "clsx";
 import { nanoid } from "nanoid";
 
 import { DrawingMode, Graph, Point, RubberBand } from "./graph";
 import { Edge, GraphData, Node } from "../type";
-import { ProbabilitySelector, percentage, reduceToSum } from "./probability-selector";
+
+import { DragIcon } from "./drawing/drag-icon";
+import { NodeModal } from "./drawing/node-modal";
 
 import SelectIcon from "../assets/select-icon.svg";
 import AddNodeIcon from "../assets/add-node-icon.svg";
@@ -13,116 +15,6 @@ import DeleteIcon from "../assets/delete-icon.svg";
 
 import "./drawing.scss";
 
-interface NodeModalProps {
-  node?: Node,
-  graph: GraphData;
-  onChange: (id: string, newNode: Node, newEdge: Edge[]) => void,
-  onCancel: () => void
-}
-
-export const NodeModal = ({node, graph, onChange, onCancel}: NodeModalProps) => {
-  const [label, setLabel] = useState(node?.label || "");
-  const [exactPercentages, _setExactPercentages] = useState<number[]>([]);
-
-  const setExactPercentages = useCallback((percentages: number[]) => {
-    // make sure percentages add up to exactly 100%
-    const allButLastSum = reduceToSum(percentages.slice(0, -1));
-    percentages[percentages.length - 1] = 100 - allButLastSum;
-    _setExactPercentages(percentages);
-  }, [_setExactPercentages]);
-
-  const fromEdges = useMemo(() => {
-    return node ? graph.edges.filter(e => e.from === node.id) : [];
-  }, [node, graph.edges]);
-
-  const edgeLabels = useMemo(() => {
-    const labels = graph.nodes.reduce<Record<string,string>>((acc, cur) => {
-      acc[cur.id] = cur.label;
-      return acc;
-    }, {});
-    return fromEdges.map(e => labels[e.to]);
-  }, [graph.nodes, fromEdges]);
-
-  const edgeValues = useMemo(() => fromEdges.map(e => e.value), [fromEdges]);
-  const sum = useMemo(() => reduceToSum(edgeValues), [edgeValues]);
-
-  useEffect(() => {
-    const percentages = edgeValues.map(edgeValue => percentage(edgeValue / sum));
-    setExactPercentages(percentages);
-  }, [edgeValues, sum, setExactPercentages]);
-
-  useEffect(() => {
-    setLabel(node?.label || "");
-  }, [node, setLabel]);
-
-  const handleSubmit = useCallback((e: React.FormEvent) => {
-    e.preventDefault();
-    if (node) {
-      let valueIndex = 0;
-      const newEdges = graph.edges.map(edge => {
-        if (edge.from === node.id) {
-          const value = sum * exactPercentages[valueIndex++];
-          return {...edge, value};
-        } else {
-          return edge;
-        }
-      });
-      onChange(node.id, {...node, label: label.trim()}, newEdges);
-    }
-  }, [label, node, exactPercentages, graph.edges, sum, onChange]);
-
-  const handleChangeLabel = (e: React.ChangeEvent<HTMLInputElement>) => {
-    setLabel(e.target.value);
-  };
-
-  if (!node) {
-    return null;
-  }
-
-  return (
-    <>
-      <div className="nodeModalBackground" />
-      <div className="nodeModal">
-        <div className="nodeModalContent">
-          <div className="nodeModalTitle">Update State</div>
-          <form onSubmit={handleSubmit}>
-            <input type="text" value={label} onChange={handleChangeLabel} autoFocus={true} />
-            <ProbabilitySelector
-              exactPercentages={exactPercentages}
-              edgeLabels={edgeLabels}
-              onChange={setExactPercentages}
-            />
-            <div className="nodeModalButtons">
-              <button type="submit">Save</button>
-              <button onClick={onCancel}>Cancel</button>
-            </div>
-          </form>
-        </div>
-      </div>
-    </>
-  );
-};
-
-export const DragIcon = ({drawingMode}: {drawingMode: DrawingMode}) => {
-  const [style, setStyle] = useState<React.CSSProperties>({});
-
-  useEffect(() => {
-    const mouseHandler = (e: MouseEvent) => setStyle({left: e.clientX - 20, top: e.clientY - 20});
-    window.addEventListener("mousemove", mouseHandler);
-    return () => window.removeEventListener("mousemove", mouseHandler);
-  }, []);
-
-  if (drawingMode === "addEdge") {
-    return <div className="dragIcon" style={style}><AddEdgeIcon /></div>;
-  }
-  if (drawingMode === "addNode") {
-    return <div className="dragIcon" style={style}><AddNodeIcon /></div>;
-  }
-  if (drawingMode === "delete") {
-    return <div className="dragIcon" style={style}><DeleteIcon /></div>;
-  }
-  return null;
-};
 
 interface Props {
   highlightNode?: Node,
diff --git a/src/components/drawing/drag-icon.tsx b/src/components/drawing/drag-icon.tsx
new file mode 100644
index 0000000..121b1d4
--- /dev/null
+++ b/src/components/drawing/drag-icon.tsx
@@ -0,0 +1,26 @@
+import React, { useEffect, useState } from "react";
+import { DrawingMode } from "../graph";
+import AddNodeIcon from "../../assets/add-node-icon.svg";
+import AddEdgeIcon from "../../assets/add-edge-icon.svg";
+import DeleteIcon from "../../assets/delete-icon.svg";
+
+export const DragIcon = ({ drawingMode }: { drawingMode: DrawingMode; }) => {
+  const [style, setStyle] = useState<React.CSSProperties>({});
+
+  useEffect(() => {
+    const mouseHandler = (e: MouseEvent) => setStyle({ left: e.clientX - 20, top: e.clientY - 20 });
+    window.addEventListener("mousemove", mouseHandler);
+    return () => window.removeEventListener("mousemove", mouseHandler);
+  }, []);
+
+  if (drawingMode === "addEdge") {
+    return <div className="dragIcon" style={style}><AddEdgeIcon /></div>;
+  }
+  if (drawingMode === "addNode") {
+    return <div className="dragIcon" style={style}><AddNodeIcon /></div>;
+  }
+  if (drawingMode === "delete") {
+    return <div className="dragIcon" style={style}><DeleteIcon /></div>;
+  }
+  return null;
+};
diff --git a/src/components/drawing/node-modal.tsx b/src/components/drawing/node-modal.tsx
new file mode 100644
index 0000000..85ad0b2
--- /dev/null
+++ b/src/components/drawing/node-modal.tsx
@@ -0,0 +1,92 @@
+import React, { useCallback, useEffect, useMemo, useState } from "react";
+import { ProbabilitySelector, percentage, reduceToSum } from "./probability-selector";
+import { Node, Edge, GraphData } from "../../type";
+
+export interface NodeModalProps {
+  node?: Node,
+  graph: GraphData;
+  onChange: (id: string, newNode: Node, newEdge: Edge[]) => void,
+  onCancel: () => void
+}
+
+export const NodeModal = ({ node, graph, onChange, onCancel }: NodeModalProps) => {
+  const [label, setLabel] = useState(node?.label || "");
+  const [exactPercentages, _setExactPercentages] = useState<number[]>([]);
+
+  const setExactPercentages = useCallback((percentages: number[]) => {
+    // make sure percentages add up to exactly 100%
+    const allButLastSum = reduceToSum(percentages.slice(0, -1));
+    percentages[percentages.length - 1] = 100 - allButLastSum;
+    _setExactPercentages(percentages);
+  }, [_setExactPercentages]);
+
+  const fromEdges = useMemo(() => {
+    return node ? graph.edges.filter(e => e.from === node.id) : [];
+  }, [node, graph.edges]);
+
+  const edgeLabels = useMemo(() => {
+    const labels = graph.nodes.reduce<Record<string, string>>((acc, cur) => {
+      acc[cur.id] = cur.label;
+      return acc;
+    }, {});
+    return fromEdges.map(e => labels[e.to]);
+  }, [graph.nodes, fromEdges]);
+
+  const edgeValues = useMemo(() => fromEdges.map(e => e.value), [fromEdges]);
+  const sum = useMemo(() => reduceToSum(edgeValues), [edgeValues]);
+
+  useEffect(() => {
+    const percentages = edgeValues.map(edgeValue => percentage(edgeValue / sum));
+    setExactPercentages(percentages);
+  }, [edgeValues, sum, setExactPercentages]);
+
+  useEffect(() => {
+    setLabel(node?.label || "");
+  }, [node, setLabel]);
+
+  const handleSubmit = useCallback((e: React.FormEvent) => {
+    e.preventDefault();
+    if (node) {
+      let valueIndex = 0;
+      const newEdges = graph.edges.map(edge => {
+        if (edge.from === node.id) {
+          const value = sum * exactPercentages[valueIndex++];
+          return { ...edge, value };
+        } else {
+          return edge;
+        }
+      });
+      onChange(node.id, { ...node, label: label.trim() }, newEdges);
+    }
+  }, [label, node, exactPercentages, graph.edges, sum, onChange]);
+
+  const handleChangeLabel = (e: React.ChangeEvent<HTMLInputElement>) => {
+    setLabel(e.target.value);
+  };
+
+  if (!node) {
+    return null;
+  }
+
+  return (
+    <>
+      <div className="nodeModalBackground" />
+      <div className="nodeModal">
+        <div className="nodeModalContent">
+          <div className="nodeModalTitle">Update State</div>
+          <form onSubmit={handleSubmit}>
+            <input type="text" value={label} onChange={handleChangeLabel} autoFocus={true} />
+            <ProbabilitySelector
+              exactPercentages={exactPercentages}
+              edgeLabels={edgeLabels}
+              onChange={setExactPercentages} />
+            <div className="nodeModalButtons">
+              <button type="submit">Save</button>
+              <button onClick={onCancel}>Cancel</button>
+            </div>
+          </form>
+        </div>
+      </div>
+    </>
+  );
+};
diff --git a/src/components/probability-selector.scss b/src/components/drawing/probability-selector.scss
similarity index 100%
rename from src/components/probability-selector.scss
rename to src/components/drawing/probability-selector.scss
diff --git a/src/components/probability-selector.tsx b/src/components/drawing/probability-selector.tsx
similarity index 100%
rename from src/components/probability-selector.tsx
rename to src/components/drawing/probability-selector.tsx