font-variant-caps「英大文字での表示制御」

<style type="text/css">
.common div{
  font-family   : "メイリオ", sans-serif;
  width         : 290px;
  border        : 2px solid #6495ed;
  background    : #e7e7ff;
  padding       : 10px;
}
div.cssTitle {
  margin-top    : 10px;
  background    : #6495ed;
  color         : #fff;
  font-weight   : bold;
}
.css-smcp{font-feature-settings: "smcp";}
.css-c2sc{font-feature-settings: "c2sc";}

.css-caps-normal{font-variant-caps :  normal;}
.css-caps-small{font-variant-caps :  small-caps;}
.css-caps-all-small{font-variant-caps :  all-small-caps;}

.css-variant-small{font-variant: small-caps;}
.css-variant-all-small{font-variant: all-small-caps;}

<!-- html -->
<div class="common">
  <div class="cssTitle">小文字→小さい大文字<br>
  font-variant-caps: small-caps</div>
  <div>
  <span class="css-caps-normal">
  To Small Caps</span><br>
  <span class="css-smcp">
  To Small Caps</span><br>
  <span class="css-caps-small">
  To Small Caps</span><br>
  <span class="css-variant-small">
  To Small Caps</span>
  </div>
  <div class="cssTitle">全ての英字→小さい大文字<br>
  font-variant-caps: all-small-caps</div>
  <div>
  <span class="css-caps-normal">
  All Small Caps</span><br>
  <span class="css-c2sc">
  All Small Caps</span><br>
  <span class="css-caps-all-small">
  All Small Caps</span><br>
  <span class="css-variant-all-smally">
  All Small Caps</span>
  </div>
</div>