初始化

Change-Id: I626ae7fe177226b54e263cc8f7703a7f55920b40
diff --git a/app/app.css b/app/app.css
new file mode 100644
index 0000000..99345d8
--- /dev/null
+++ b/app/app.css
@@ -0,0 +1,15 @@
+@import "tailwindcss";
+
+@theme {
+  --font-sans: "Inter", ui-sans-serif, system-ui, sans-serif,
+    "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
+}
+
+html,
+body {
+  @apply bg-white dark:bg-gray-950;
+
+  @media (prefers-color-scheme: dark) {
+    color-scheme: dark;
+  }
+}