Web: Editor: added global styles

web/ASC.Web.Editor/pages/_app.js

@@ -1,3 +1,20 @@
-export default function App({ Component, pageProps }) {
+import { createGlobalStyle } from "styled-components";
-  return <Component {...pageProps} />;
+
+const GlobalStyle = createGlobalStyle`
+body {
+    margin: 0;
+}
+
+html, body {
+    height: 100%;
+}
+`;
+
+export default function App({ Component, pageProps }) {
+  return (
+    <>
+      <GlobalStyle />
+      <Component {...pageProps} />
+    </>
+  );
 }