Add a small triangle to the upper right corner of the div

Add a triangle to the upper right corner of the div

As shown in the figure

code:

  <div  class="sch_box"></div>

css

.sch_box {
    
    
  width: 12px;
  height: 12px;
  background-color: #f0142f;
  transform: rotate(45deg);
  -ms-transform: rotate(45deg); /* Internet Explorer */
  -moz-transform: rotate(45deg); /* Firefox */
  -webkit-transform: rotate(45deg); /* Safari 和 Chrome */
  -o-transform: rotate(45deg); /* Opera */
  position: absolute;
  right: -6px;
  top: -6px;
}

For outer div

 position: relative;