<!DOCTYPE html>
<style>
html {
  font-family: Ahem;
  font-size: 20px;
  line-height: 1;
}
.container {
  white-space: pre;
  margin-bottom: 1em;
}
.float {
  float: left;
  width: 3ch;
  height: 2em;
  background: orange;
}
</style>
<body>
  <div class="float"></div>
  <div class="container">123456<br>123456</div>
  <div class="float"></div>
  <div class="container">1234567<br>1234567</div>
  <div class="float"></div>
  <div class="container">1234567<br>1234567</div>
  <div class="float"></div>
  <div class="container">1234567<br>1234567</div>
  <div class="float"></div>
  <div class="container"><br><br>12345678<br>12345678</div>
</body>