style: emotion theme 적용

src/main.tsx

@@ -1,11 +1,15 @@
 import React from 'react';
 
+import { ThemeProvider } from '@emotion/react';
 import ReactDOM from 'react-dom/client';
 
 import App from './App.tsx';
+import { theme } from './styles/theme.ts';
 
 ReactDOM.createRoot(document.getElementById('root')!).render(
   <React.StrictMode>
-    <App />
+    <ThemeProvider theme={theme}>
+      <App />
+    </ThemeProvider>
   </React.StrictMode>,
 );

src/styles/emotion.d.ts

@@ -0,0 +1,13 @@
+import '@emotion/react';
+
+type colors = 'primary' | 'positive' | 'negative';
+
+declare module '@emotion/react' {
+  export interface Theme {
+    colors: {
+      primary: string;
+      positive: string;
+      negative: string;
+    };
+  }
+}

src/styles/theme.ts

@@ -0,0 +1,7 @@
+export const theme = {
+  colors: {
+    primary: 'hotpink',
+    positive: 'green',
+    negative: 'red',
+  },
+};