Check out example codes for "disable scroll css". It will help you in understanding the concepts better.

Code Example 1

/* Answer to: "disable scroll css" */

/*
  You must set the height and overflow of the body, to disable
  scrolling.
*/

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden
}

Code Example 2

html { overflow-y: hidden; }

Code Example 3

::-webkit-scrollbar {
  -webkit-appearance: none;
  width: 7px;
}
::-webkit-scrollbar-thumb {
  border-radius: 4px;
  background-color: rgba(0, 0, 0, .5);
  -webkit-box-shadow: 0 0 1px rgba(255, 255, 255, .5);
}

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