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<!DOCTYPE html>
<html>
<head>
<style>
#container {
  width: 80%;
  aspect-ratio: 3/1;
  margin: auto;
  border: solid black 2px;
  overflow-x: hidden;
  overflow-y: scroll;
  scroll-snap-type: y mandatory;
  scroll-padding-top: 20px;
}

.blue {
  background-color: lightblue;
  width: 95%;
  aspect-ratio: 3/1;
}

.green {
  background-color: lightgreen;
  width: 80%;
  aspect-ratio: 4/1;
}

.blue, .green {
  margin: 2px;
  scroll-snap-align: start;
}
</style>
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<h3>CSS scroll-padding-top property.</h3>
<p>Scroll-padding-top property is set on the container, so that the snap position of child elements is offset by a distance to the top of the container.</p>
<p>In this case, snap position is set to start in y direction, so the element in focus should snap into place at the very top of the container. But instead, because of the scroll-padding-top value, the element in focus is offset by a 20px distance from the top of the container to the child element.</p>

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