<small>: side-comment 元素

<p>
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<p>
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    >The content is licensed under a Creative Commons Attribution-ShareAlike 2.5
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small {
  font-size: 0.7em;
}

<p>
  This is the first sentence.
  <small>This whole sentence is in small letters.</small>
</p>

<p>
  This is the first sentence.
  <span class="small">This whole sentence is in small letters.</span>
</p>

.small {
  font-size: 0.8em;
}