diff --git a/app/globals.css b/app/globals.css
new file mode 100644
index 0000000..66fa89e
--- /dev/null
+++ b/app/globals.css
@@ -0,0 +1,11 @@
+*,
+*::before,
+*::after {
+  box-sizing: border-box;
+}
+
+html,
+body {
+  margin: 0;
+  padding: 0;
+}
diff --git a/app/layout.js b/app/layout.js
index 24dff5d..f1a476d 100644
--- a/app/layout.js
+++ b/app/layout.js
@@ -1,3 +1,5 @@
+import './globals.css';
+
 export const metadata = {
   title: 'Kosuke Pokemon Platform',
 };
diff --git a/app/page.js b/app/page.js
index d49ff1c..7769606 100644
--- a/app/page.js
+++ b/app/page.js
@@ -20,7 +20,7 @@ export default function Home() {
         gap: '2rem',
         padding: '2rem',
         fontFamily: 'system-ui, sans-serif',
-        background: 'linear-gradient(160deg, #fdfbfb 0%, #ebedee 100%)',
+        background: 'linear-gradient(160deg, #ffb457 0%, #f97316 100%)',
       }}
     >
       <h1 style={{ margin: 0, textAlign: 'center', color: '#1a1a1a' }}>