Fix "+" button hides "download" and "trash" buttons

How to reproduce

• Login with Administrator account
• Go to Workspaces > Discover Customization Examples > BigCorp Transforms GreatBank Customer Service
• Click on GENERATE PROJECT REVENUE SHEET button and render a template.
• Click on the top right "Add to collection" button and add the project to the "Financial Services Industry Related Projects" collection.
• Go to "Financial Services Industry Related Projects" portfolio
• Scroll Down

See attach

Proposed solution
Add margin-bottom on the document-preview element.