HTML, CSS and Bootstrap Practice

Instruction: Take a look at the image provided and try to produce a similar output.

No.	Image	Output
1.	Hint: Use flexbox, border and padding	Item 1 for Flex Item 2 for Flex Item 3 for Flex
2.	Hint: Use Bootstrap button	button
3.	Hint: Make a flexbox with black border. Then make a red square (50px) inside flexbox using CSS first