diff --git a/examples/expo-example/app.json b/examples/expo-example/app.json
index 00391a7..2be12af 100644
--- a/examples/expo-example/app.json
+++ b/examples/expo-example/app.json
@@ -27,9 +27,7 @@
 		},
 		"web": {
 			"build": {
-				"babel": {
-					"include": ["@yoshiki/native", "@yoshiki/core"]
-				}
+				"bundler": "metro"
 			},
 			"favicon": "./assets/favicon.png"
 		}
diff --git a/examples/expo-example/metro.config.js b/examples/expo-example/metro.config.js
index f79958b..ad0672d 100644
--- a/examples/expo-example/metro.config.js
+++ b/examples/expo-example/metro.config.js
@@ -14,7 +14,10 @@ const workspaceRoot = path.resolve(projectRoot, "../..");
 const config = getDefaultConfig(projectRoot);
 
 // 1. Watch all files within the monorepo
-config.watchFolders = [workspaceRoot];
+config.watchFolders = [
+	path.resolve(workspaceRoot, "examples/expo-example"),
+	path.resolve(workspaceRoot, "packages"),
+];
 // 2. Let Metro know where to resolve packages and in what order
 config.resolver.nodeModulesPaths = [
 	path.resolve(projectRoot, "node_modules"),
diff --git a/examples/expo-example/src/app.tsx b/examples/expo-example/src/app.tsx
index f125a12..511a73d 100644
--- a/examples/expo-example/src/app.tsx
+++ b/examples/expo-example/src/app.tsx
@@ -18,7 +18,7 @@ const CustomBox = ({ color, ...props }: { color: string }) => {
 
 const BoxWithoutProps = (props: object) => {
 	return (
-		<View {...css({ backgroundColor: "#999999" }, props)}>
+		<View {...css({ backgroundColor: { xs: "00ff00", md: "#ff0000"} }, props)}>
 			<Text>Text inside the box without props</Text>
 		</View>
 	);
diff --git a/examples/expo-example/webpack.config.js b/examples/expo-example/webpack.config.js
new file mode 100644
index 0000000..76d9329
--- /dev/null
+++ b/examples/expo-example/webpack.config.js
@@ -0,0 +1,18 @@
+//
+// Copyright (c) Zoe Roux and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for details.
+//
+const createExpoWebpackConfigAsync = require("@expo/webpack-config");
+
+module.exports = async function (env, argv) {
+	const config = await createExpoWebpackConfigAsync(
+		{
+			...env,
+			babel: {
+				dangerouslyAddModulePathsToTranspile: ["@yoshiki"],
+			},
+		},
+		argv,
+	);
+	return config;
+};
diff --git a/packages/core/src/type.ts b/packages/core/src/type.ts
index 70bfbd7..d42ce39 100644
--- a/packages/core/src/type.ts
+++ b/packages/core/src/type.ts
@@ -8,14 +8,20 @@ export type Theme = {
 	spacing: string;
 };
 
+export const breakpoints = {
+	xs: 0,
+	sm: 600,
+	md: 900,
+	lg: 1200,
+	xl: 1600,
+}
+
 export type YoushikiStyle<Property> =
 	| Property
 	| ((theme: Theme) => Property)
 	| Breakpoints<Property>;
 
+
 export type Breakpoints<Property> = {
-	sm?: Property;
-	md?: Property;
-	lg?: Property;
-	xl?: Property;
+	[key in keyof (typeof breakpoints)]?: Property;
 };
diff --git a/packages/native/src/index.tsx b/packages/native/src/index.tsx
index a8476e0..bc12dc7 100644
--- a/packages/native/src/index.tsx
+++ b/packages/native/src/index.tsx
@@ -3,21 +3,51 @@
 // Licensed under the MIT license. See LICENSE file in the project root for details.
 //
 
-import { ViewStyle, TextStyle, ImageStyle } from "react-native";
-import { YoushikiStyle } from "@yoshiki/core";
+import { ViewStyle, TextStyle, ImageStyle, useWindowDimensions } from "react-native";
+import { breakpoints, Breakpoints, YoushikiStyle } from "@yoshiki/core";
 
 // TODO: shorhands
 type EnhancedStyle<Properties> = {
 	[key in keyof Properties]: YoushikiStyle<Properties[key]>;
 };
-export type CssObject = EnhancedStyle<ViewStyle> | EnhancedStyle<TextStyle> | EnhancedStyle<ImageStyle>;
+export type CssObject =
+	| EnhancedStyle<ViewStyle>
+	| EnhancedStyle<TextStyle>
+	| EnhancedStyle<ImageStyle>;
 type Properties = ViewStyle | TextStyle | ImageStyle;
 
+const useBreakpoint = (): number => {
+	const { width } = useWindowDimensions();
+	const idx = Object.values(breakpoints).findIndex((x) => width <= x);
+	if (idx === -1) return 0;
+	return idx - 1;
+};
+
 export const css = (css: CssObject, leftOvers?: { style?: Properties }) => {
 	const { style, ...leftOverProps } = leftOvers ?? {};
 
+	let breakpoint: number | undefined = undefined;
+	const ret: Properties = Object.fromEntries(
+		Object.entries(css)
+			.map(([key, value]) => {
+				if (typeof value === "object") {
+					if (!breakpoint) breakpoint = useBreakpoint();
+
+					const bpKeys = Object.keys(breakpoints);
+					for (let i = breakpoint; i >= 0; i--) {
+						if (bpKeys[i] in value) {
+							return [key, value[bpKeys[i]]];
+						}
+					}
+					return undefined;
+				}
+				return [key, value];
+			})
+			.filter((x) => x !== undefined),
+	);
+
 	return {
-		style: { ...css, ...style } as Properties,
+		style: { ...ret, ...style },
 		...leftOverProps,
 	};
 };
diff --git a/packages/native/tsconfig.json b/packages/native/tsconfig.json
index 32ca157..b65f7f9 100755
--- a/packages/native/tsconfig.json
+++ b/packages/native/tsconfig.json
@@ -1,5 +1,6 @@
 {
 	"compilerOptions": {
+		"noErrorTruncation": true,
 		"target": "es5",
 		"lib": ["dom", "dom.iterable", "esnext"],
 		"declaration": true,