How to add a circle on the top right corner of a button above the background and behind the border?

Question

I wanna achieve the following result by using CSS:

So basically I want the circle to be on top of the button background but behind its border, with the butt

Answer 1

Use a pseudo element (::after) to draw the border above the circle:

.container {
  margin-top: 30px;
}

button {
  position: relative;
  font-size: 20px;
  border: none;
  padding: 8px 20px;
}

button::before {
  position: absolute;
  top: -20px;
  right: -20px;
  width: 40px;
  height: 40px;
  border-radius: 25px;
  background: #4da6ff;
  content: '';
}

button::after {
  position: absolute;
  top: -2px;
  right: -2px;
  bottom: -2px;
  left: -2px;
  border: 2px solid black;
  content: '';
}

  Test Button