SVG file changes colour in Photoshop

Hi all, 

Beginner illustrator/photoshop user here so bear with me. 

I have created a design using illustrator - the file is RGB

This is what it looks like as a .ai document and a PNG

however when I export it as .SVG it changes the colours on certain browsers, and within Photoshop. 

These colour changes do not happen on Chrome or Microsoft Excel for some bizarre reason. 

I have no idea to fix it - I've tried playing with the export settings and it's not helping. 

Any advice appreciated! 
I need to be able to produce the artwork not only as a .ai file but as .svg so I can't just stick with the illsutrator version. 

Thank you!