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                <div class="box">
  <!-- ↓spanでなく、pやhでも大丈夫です -->
  <span class="title">注意点</span>


                .box {
  position: relative;
  padding: 16px;
  /* 枠の色や太さなどお好みで */
  border: #E00700 3px solid;
  border-radius: 5px;

.box .title {
  display: inline-block;
  position: absolute;
  /* 位置の調整は適宜 */
  top: -13px;
  left: 10px;
  padding: 0 9px;
  /* 周りの背景と同じ色を当てる */
  background-color: #fff;