Editing Title, Sub title and Text

In the web app we are making theres a Material Design Card where theres a User type that has the permission to edit content he posted, so heres the question.

When he clicks to edit this content every line is going to convert to a Text field or Text Area as needed BUT the TITLE for example has a bigger size font so we don't know if the new words on the input of the title should use the same font size as the Title or it should be the same font size as a body?

(THE "NOMBRE CORTO" SHOULD TRANSFORM TO A TEXT FIELD WHEN EDITING MODE ITS ON AND SO THE SUB HEADING AND BODY)

Below you guys can find the screen shot and as always the material design link related to this subject.

https://www.google.com/design/spec/components/text-fields.html