Simple shader in orthographic mode

I have a simple shader I basically copied from the very basic tutorials:

 Shader "Custom/FadeOverlay" {
     Properties {
     _Color ("Main Color", Color) = (1,0.5,0.5,1)
     }
     SubShader {
         Pass {
             Material {
                 Diffuse [_Color]
             }
         }
     }
 }

I have a 2D project and thus my camera is orthophedic. I have a single quad that I stretch to be screen size and apply a material based off this shader to the quad (that doesn't cast or receive shadows).

The result in Scene mode is a red square (due to me selecting Main Color as red). However, when I run it - the quad gets scaled but it's black as night.

I am completely new to Unity shaders and I have no idea why the simple example in orthogonal mode would do this.