<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:sys="clr-namespace:System;assembly=mscorlib">

    <FontFamily x:Key="Font.Family.Default">/#Nunito Sans Regular</FontFamily>
    <sys:Double x:Key="Font.Size.Header">17</sys:Double>
    <sys:Double x:Key="Font.Size.Normal">15</sys:Double>
    <sys:Double x:Key="Font.Size.ToolTip">12</sys:Double>

</ResourceDictionary>