■影shadow 角丸rounded:ユーティリティ:影Shadowsユーティリティ

影なし(shadow-none)
小さめの影(shadow-sm)
標準の影(shadow)
大きめの影(shadow-lg)
  <div class="shadow-none p-3 mb-5 bg-light rounded">影なし(shadow-none)</div>
  <div class="shadow-sm p-3 mb-5 bg-light rounded">小さめの影(shadow-sm)</div>
  <div class="shadow p-3 mb-5 bg-light rounded">標準の影(shadow)</div>
  <div class="shadow-lg p-3 mb-5 bg-light rounded">大きめの影(shadow-lg)</div>
■影shadow 角丸rounded:ユーティリティ:角丸を設定するクラス rounded

rounded rounded-top rounded-right rounded-bottom rounded-left rounded-circle 正円 rounded-0
<span class="rounded">rounded</span>
<span class="rounded-top">rounded-top</span>
<span class="rounded-right">rounded-right</span>
<span class="rounded-bottom">rounded-bottom</span>
<span class="rounded-left">rounded-left</span>
<span class="rounded-circle">rounded-circle</span>
<span class="rounded-circle" id="circle">正円</span><!-- 幅と高さを同じ(100px)に設定 -->
<span class="rounded-0">rounded-0</span>