Grace:

• Not sure about the right-aligned text. Kind of hard to read. Probably left-align all of it.
• First desktop-sized postcard—read the text on the left first. Also, not sure how the text will move as the screen size is scaled down.
• The others seem more easily buildable, and you’ll be able to code them simply.
• Typeface, size changes, weight changes & colors are nice. Consider adding images? The postcards look a little boring right now.
• On “come on kid,” ideally kid wouldn’t be on its own line (it looks too short—widow).