Within Lectora you have the option to change the background color and the text style of the text used within the Entry Field – you can find these options on the Entry Field’s Properties Ribbon.
To add additional styling options, such as a border, you can take advantage of CSS. Use the CSS Classes option by selecting the arrow on the Appearance Panel of the Entry Field’s Properties Ribbon to assign a CSS class to the entry field.
Then specify a border color for that class within a CSS File that you can add via an HTML Extension object. Once you do that, you can assign that CSS class to other objects within your title, and they’ll take on the same border attribute.