what is color stop? plz describe easily......

Answer 1

As you probably know gradients are typically one color that fades into another, but in CSS you can control every aspect of how that happens, from the direction to the colors to where those color changes happen. Thus colors and stops tell the browser which colors to use in the gradients, and where they should stop.
Say you wanted yellow to take up the majority of the space, but red only a little bit in the beginning, you could make the yellow color-stop pretty early:
html
<div class="gradient">
</div>
css

.gradient { height: 100px; background-color: red; background-image: linear-gradient( to right, red, yellow 10% ); }

Answer 2

many many thanks.. @lana wilson .

Answer 3

answer of that question is 20%