Tidy up split phrase warning

Make red only when danger is present
Align neatly with the rest of the UI
Increase size of text area to show all three rows, although it still
overflows on 24 words.

src/css/app.css

@@ -31,10 +31,6 @@ body {
 .phrase {
     word-break: keep-all;
 }
-.phraseSplitWarn {
-	text-align: right;
-	color: red;
-}
 .generate-container .strength {
     /* override mobile width from bootstrap */
     width: auto!important;