feat: revamp demo

demo/data/bar.ts

@@ -0,0 +1,46 @@
+import type { Option } from "../../src/types";
+import { DEMO_TEXT_STYLE } from "../constants";
+
+function random(): number {
+  return Math.round(300 + Math.random() * 700) / 10;
+}
+
+export default function getData(): Option {
+  const option = {
+    textStyle: { ...DEMO_TEXT_STYLE },
+    dataset: {
+      dimensions: ["Product", "2015", "2016", "2017"],
+      source: [
+        {
+          Product: "Matcha Latte",
+          2015: random(),
+          2016: random(),
+          2017: random(),
+        },
+        {
+          Product: "Milk Tea",
+          2015: random(),
+          2016: random(),
+          2017: random(),
+        },
+        {
+          Product: "Cheese Cocoa",
+          2015: random(),
+          2016: random(),
+          2017: random(),
+        },
+        {
+          Product: "Walnut Brownie",
+          2015: random(),
+          2016: random(),
+          2017: random(),
+        },
+      ],
+    },
+    xAxis: { type: "category" },
+    yAxis: {},
+    series: [{ type: "bar" }, { type: "bar" }, { type: "bar" }],
+  } satisfies Option;
+
+  return option;
+}