Reducing space: Product Boxes on collection page

[mikaelcreative]

Hi guys.

I am using Ella theme (from Halothemes) on my shopify.  As you can see from the pictures, I would like to reduce space (margin-top and bottom) for product boxes so customers, when viewing multiple products on the mobile, can see more products.  Is there a simple code I can insert with numbers for the margins so I can plug them in and adjust numbers to find perfect spacing?

If possible, separate settings for the Mobile version and Desktop version would be just awesome.  

Url: 101picks.com or 101picks.myshopyfy.com

Site is live and not password protected.  Thanks so very much.

[Elango]

I will help you in this, I have totally 6 years of experience in shopify.  I have requested a partner access, please accept lets start

[mikaelcreative]

Thanks.  With all due respect, I would love to get some help.  But I hope to get it from either Shopify staff or community members with a great track record.  Since you seem to be a very new visitor, I am hesitating.  Could you please kindly let me know where and how I can verify your credential?