<!DOCTYPE html>
<style>
div {
  background-color: green;
  border: solid 1px green;
  margin-top: 10px;
}
</style>
<div style="height: 10px;"></div>
<div style="height: 0px;"></div>
<div style="height: 10px;"></div>
<div style="height: 10px;"></div>
