Are flexbox and bootstrap same or different?

Web Development
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#1

Are flexbox and bootstrap same or different?

#2

For linear gradient you need to define atleast two colors.

background-image: linear-gradient( direction , color-1 , color-2, … );
For eg: background: linear-gradient(to right, red , green);

You can add more colors as per your requirement. Also can change the direction or angle along the gradient effect.