1. 4.x modules/tinymce/inc/tiny_mce/plugins/template/css/template.css
2. 5.x modules/tinymce/inc/tiny_mce/plugins/template/css/template.css

#frmbody {
	padding: 10px;
	background-color: #FFF;
	border: 1px solid #CCC;
}

.frmRow {
	margin-bottom: 10px;
}

#templatesrc {
	border: none;
	width: 320px;
	height: 240px;
}

.title {
	padding-bottom: 5px;
}

.mceActionPanel {
	padding-top: 5px;
}

File

#frmbody {
	padding: 10px;
	background-color: #FFF;
	border: 1px solid #CCC;
}

.frmRow {
	margin-bottom: 10px;
}

#templatesrc {
	border: none;
	width: 320px;
	height: 240px;
}

.title {
	padding-bottom: 5px;
}

.mceActionPanel {
	padding-top: 5px;
}