.course_index .item_course {
  display: block;
  width: 32%;
  margin-right: 2%;
  background: #f7f9fa;
  margin-top: 0.3rem;
  position: relative;
  overflow: hidden;-webkit-transition: all .3s linear;transition: all .3s linear;
}
.course_index .item_course:nth-of-type(3n) {
  margin-right: 0px;
}

.course_index .item_course .pic{display: flex; justify-content: center; align-items: center; height: 3rem; background: #ffffff;}
.course_index .item_course .pic img{max-height: 100%; width: 100%;}
.course_index .item_course .nr{}
.course_index .item_course .nr h3{text-overflow: ellipsis;  display: -webkit-box;  -webkit-box-orient: vertical;  -webkit-line-clamp: 1;}
.course_index .item_course .nr p{line-height: 1.8;overflow: hidden; text-overflow: ellipsis;  display: -webkit-box;  -webkit-box-orient: vertical;  -webkit-line-clamp: 2;}
.course_index .item_course .nr span{color: #ff4c5b; font-weight: bold;}
.course_index .item_course .nr button{display: none; border: none; background-color: #ff4c5b; color: #fff; padding: 0.07rem 0.35rem;}
.course_index .item_course:hover{box-shadow: 0 0 7px -2px #cbc9c9;}
.course_index .item_course:hover .nr button {display: block;}