SOURCE

<div class="folder-box">
	<div class="folder-label">
     文件名称
  </div>
  <div class="folder-corner"></div>
  <div class="folder-contain">
    <div class="folder-content">
      文件内容
    </div>
  </div>
</div>

.folder-box{
  width: 200px;
  height: 200px;
  position: relative;
  margin-top: 50px;
  color: #fff;
}
.folder-label{
  height: 30px;
  line-height: 30px;
  position: absolute;
  background-color: orange;
  top: -30px;
  padding: 0 10px;
  border-top-left-radius: 4px;
}
.folder-corner{
  border:15px solid #000; 
  border-color: transparent transparent orange orange;
  position: absolute;
  top: -30px;
  left: 84px;
}
.folder-contain{
  width: 100%;
  height: calc(100% - 30px);
  background-color: orange;
  padding-top: 12px;
  border-bottom-left-radius: 4px;
  border-bottom-right-radius: 4px;
  border-top-right-radius: 4px;
}
.folder-content{
  padding: 10px;
  background-color: #ffc800;
  height: calc(100% - 20px);
}