How to turn on fog on this shader

the fog in the scene dosn't affect the mesh with this shader, how to turn it on ?

 Shader "TSF/BaseOutline1"
 {
     Properties 
     {
 
         [MaterialToggle(_TEX_ON)] _DetailTex ("Enable Detail texture", Float) = 0     //1
         _MainTex ("Detail", 2D) = "white" {}                                        //2
         _ToonShade ("Shade", 2D) = "white" {}                                          //3
         [MaterialToggle(_COLOR_ON)] _TintColor ("Enable Color Tint", Float) = 0     //4
         _Color ("Base Color", Color) = (1,1,1,1)                                    //5    
         [MaterialToggle(_VCOLOR_ON)] _VertexColor ("Enable Vertex Color", Float) = 0//6        
         _Brightness ("Brightness 1 = neutral", Float) = 1.0                            //7    
         _OutlineColor ("Outline Color", Color) = (0.5,0.5,0.5,1.0)                    //10
         _Outline ("Outline width", Float) = 0.01                                    //11
 
     }
  
     SubShader
     {
         Tags { "RenderType"="Opaque" }
         LOD 250 
         Lighting Off
         Fog { Mode Global  }
         UsePass "TSF/Base1/BASE"
             
         Pass
         {
             Cull Front
             ZWrite On
             CGPROGRAM
             #include "UnityCG.cginc"
             #pragma fragmentoption ARB_precision_hint_fastest
             #pragma glsl_no_auto_normalization
             #pragma vertex vert
              #pragma fragment frag
             
             struct appdata_t 
             {
                 float4 vertex : POSITION;
                 float3 normal : NORMAL;
             };
 
             struct v2f 
             {
                 float4 pos : SV_POSITION;
             };
 
             fixed _Outline;
 
             
             v2f vert (appdata_t v) 
             {
                 v2f o;
                 o.pos = v.vertex;
                 o.pos.xyz += normalize(v.normal.xyz) *_Outline*0.01;
                 o.pos = UnityObjectToClipPos(o.pos);
                 return o;
             }
             
             fixed4 _OutlineColor;
             
             fixed4 frag(v2f i) :COLOR 
             {
                 return _OutlineColor;
             }
             
             ENDCG
         }
     }
 Fallback "Legacy Shaders/Diffuse"
 }