Check out example codes for "positioning button inside div". It will help you in understanding the concepts better.

Code Example 1

.button-div {
  position: relative;
}

.button {
  position: absolute;
  top:;     <!-- declare your own positioning -->
  left:;
}

Code Example 2

<div class="button-div">
  <button class="button" type="button" name="button"></button>
</div>

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