Removed unused top level css

no issue

- CSS was added as part of App initialization and not used in project
- Top-level css leaks through on the page when script is added unlike the frame's css/inline-style

ghost/portal/src/App.css

@@ -1,38 +0,0 @@
-.App {
-    text-align: center;
-}
-
-.App-logo {
-    height: 40vmin;
-    pointer-events: none;
-}
-
-@media (prefers-reduced-motion: no-preference) {
-    .App-logo {
-        animation: App-logo-spin infinite 20s linear;
-    }
-}
-
-.App-header {
-    background-color: #282c34;
-    min-height: 100vh;
-    display: flex;
-    flex-direction: column;
-    align-items: center;
-    justify-content: center;
-    font-size: calc(10px + 2vmin);
-    color: white;
-}
-
-.App-link {
-    color: #61dafb;
-}
-
-@keyframes App-logo-spin {
-    from {
-        transform: rotate(0deg);
-    }
-    to {
-        transform: rotate(360deg);
-    }
-}

ghost/portal/src/index.css

@@ -1,13 +0,0 @@
-body {
-  margin: 0;
-  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
-    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
-    sans-serif;
-  -webkit-font-smoothing: antialiased;
-  -moz-osx-font-smoothing: grayscale;
-}
-
-code {
-  font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New',
-    monospace;
-}