Question

Actually, I want to implement a text box as shown in the figure:

I want that the user should be able to enter the number in the required space. Note that it would be transparent so that the background is visible. A solution involving html5 canvas would also be good.

So, is it possible to do this? If so, how?

Answer 1

What have you tried so far? You pretty much answered your own question, make the input have a transparent background.

input {
    border: 0;
    outline: 0;
    background: transparent;
    border-bottom: 2px solid black;
    width: 20px;
}

jsFiddle