Image Projector

I wrote a little shader for projected images

 Shader "Sticker" { 
     Properties {
         _ColorTint ("Main Color", Color) = (1, 1, 1, 1)
         _MainTex ("Texture", 2D) = "white" {}
     }
     Subshader {
         Tags {"Queue"="Transparent"}
         Pass {
             AlphaTest Greater 0
             Blend DstColor zero
  
             CGPROGRAM
             #pragma exclude_renderers d3d11 xbox360
             #pragma vertex vert
             #pragma fragment frag
             #include "UnityCG.cginc"
             
             struct v2f {
                 float4 color : Color;
                 float2 uv_MainTex;
                 float4 uvShadow : TEXCOORD0;
                 float4 pos : SV_POSITION;
             };
             
             float4x4 _Projector;
             float4x4 _ProjectorClip;
             
             v2f vert (float4 vertex : POSITION) {
                 v2f o;
                 o.pos = mul (UNITY_MATRIX_MVP, vertex);
                 o.uvShadow = mul (_Projector, vertex);
                 return o;
             }
             
             float4 _ColorTint;
             sampler2D _MainTex;
             
             fixed4 frag (v2f i) : SV_Target {
                 i.color = _ColorTint;
                 fixed4 texS = tex2D(_MainTex, i.uv_MainTex);
                 texS.rgb *= _ColorTint;
                 
                 return texS;
             }
             
             ENDCG
         }
     }
 }

But the underground shines through the image so you can see the material projected on and I want to prevent that.

I'm not really good with shaders (I kind of guessed this script) and tries didn't work.

I searched through the internet to find codes but I hadn't find any.