add some support for unsupported browsers

index.css

@@ -2,7 +2,7 @@ body {
     margin: 0;
 }
 
-.animate, .loading {
+.animate, .loading, .warning {
     position: absolute;
     z-index: 1001;
 }
@@ -79,13 +79,17 @@ body {
     line-height: 22px;
 }
 
-
 .screen {
     width: 100%;
     height: 100%;
     z-index: 1000;    
 }
 
+.warning {
+    width: 256px;
+    text-align: justify;
+}
+
 body.OxThemeClassic,
 .OxThemeClassic .screen {
     background-color: rgb(240, 240, 240);    
@@ -116,4 +120,4 @@ body.OxThemeModern,
 }
 .OxThemeModern .readme .item.selected {
     background: rgb(32, 32, 32);
-}
+}