SettingsWindow.xaml

<Window x:Name="SettingsW" x:Class="Timer.SettingsWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Timer"
        mc:Ignorable="d"
        Title="Settings" Height="200" Width="300" ResizeMode="NoResize" Style="{DynamicResource WindowStyle}" Icon="Resources/Icon.ico" WindowStartupLocation="CenterScreen">
    
    <Grid>
        <CheckBox x:Name="CB_Theme" Content="Dark theme" Margin="30,30,145,110" FontSize="16"/>
        <CheckBox x:Name="CB_UnitInSeconds" Content="Enter time in seconds" Margin="30,70,80,70" FontSize="16"/>
        <Button x:Name="Bt_Save" Content="Save" Margin="98,110,98,20" Click="Bt_Save_Click" Template="{DynamicResource Buttons}"/>
    </Grid>
</Window>