Why is it not accepting _Color variable?

Code (CSharp):

1. Shader "Unlit Color" {
2.  
3.     Properties{
4.         _Color("Color", Color) = (1,1,1)
5.     }
6.  
7.         SubShader{
8.  
9.  
10.         Tags{
11.         "Queue" = "Transparent"
12.         "IgnoreProjector" = "True"
13.         "RenderType" = "Transparent"
14.         "PreviewType" = "Plane"
15.         "CanUseSpriteAtlas" = "True"
16.     }
17.  
18.         Pass{
19.  
20.         CGPROGRAM
21. #pragma vertex vert
22. #pragma fragment frag
23.  
24. #include "UnityCG.cginc"
25.  
26.     struct appdata
27.     {
28.         float4 vertex : POSITION;
29.         float2 uv : TEXCOORD0;
30.     };
31.  
32.     struct v2f
33.     {
34.         float2 uv : TEXCOORD0;
35.         float4 vertex : SV_POSITION;
36.     };
37.  
38.     v2f vert(appdata v)
39.     {
40.         v2f o;
41.         o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
42.         o.uv = v.uv;
43.         return o;
44.     }
45.  
46.     fixed4 frag(v2f i) : SV_Target
47.     {
48.         return _Color;
49.     }
50.         ENDCG
51.     }
52.     }
53. }

So i'm trying to write a really basic fill with 1 color shader.

The problem is the line 48 is giving me error, why is it not accepting the variable _Color from Properties?

 

You need a fixed4 _Color; someplace inside the CGPROGRAM block but outside a function.

https://docs.unity3d.com/Manual/SL-PropertiesInPrograms.html

 

Thanks!