What do I need to edit?

[Bubka3]

What template and css property controls the color of this text:

 

[Jake Bunce]

Admin CP -> Appearance -> Color Palette -> @primaryLightish

Or override the CSS:

Admin CP -> Appearance -> Templates -> EXTRA.css

Add this code:

.messageList .placeholder .placeholderContent
{
	color: green !important;
}

 

[X_Plaza]

You can change color value to anything color you want