body {
  height: 100%;
}
#top_title_bg {
  float: left;
  width: 9rem;
  height:1.5rem;
  line-height: 1.5rem;
  margin-left: 0.5rem;
}
#top_title {
  float: left;
  width: 4rem;
  height:1.5rem;
  line-height: 1.5rem;
  font-size: 0.5rem; 
  font-weight: bold;
  color: #2B2B2B;
}
#top_delete_btn {
  float: right;
  width: 2rem;
  height:1.5rem;
  font-size: 0.38rem;
  color: #777;
  text-align: right;
  background-image: url(../img/icon_basket.png);
  background-repeat: no-repeat;
  background-size: 0.45rem 0.45rem;
  background-position: 0.7rem 49%;
  display: none;
}

.book_list {
  width: 9rem;
  margin-left: 0.5rem;
  margin-bottom: 0.04rem;
  display: flex;
  flex-wrap: wrap;
}
.book_list_item {
  float: left;
  width: 2.36rem;
  height: 3.4rem;
  margin-bottom: 0.5rem;
  border-radius: 0.2rem;
  margin-left: 0.96rem;
  background-color: #f7f5f6;
}
.book_list_item:nth-of-type(1),
.book_list_item:nth-of-type(4),
.book_list_item:nth-of-type(7),
.book_list_item:nth-of-type(10) {
  margin-left: 0;
}
.book_list_item_text {
  float: left;
  width: 2.36rem;
  height: 2.4rem;
  margin-top: 1rem;
  text-align: center;
  color: white;
  font-size: 0.3rem;
  padding: 0;
  position: absolute;
}
.book_list_item_img {
  width: 100%;
  height: 100%;
  border-radius: 0.2rem;
}
.book_list_item_delete {
  width: 0.5rem;
  height: 0.5rem;
  position: relative;
  right: -2.1rem;
  top: -3.66rem;
  z-index: 10;
  background-image: url('../img/icon_delete.png');
  background-size: 100% 100%;
  background-repeat: no-repeat;
  display: none;
}

.book_list_item_add {
  float: left;
  width: 2.36rem;
  height: 3.4rem;
  margin-bottom: 0.5rem;
  border-radius: 0.2rem;
  margin-left: 0.96rem;
  background-color: #f7f5f6;
}
.book_list_item_add:nth-of-type(1),
.book_list_item_add:nth-of-type(4),
.book_list_item_add:nth-of-type(7),
.book_list_item_add:nth-of-type(10) {
  margin-left: 0;
}
.book_list_item_add_img {
  width:1rem;
  height: 1rem;
  margin-left: 0.7rem;
  margin-top: 0.8rem;
}
.book_list_item_add_text {
  margin-top: 0.25rem;
  text-align: center;
  color: #7d7a7d;
  font-size: 0.35rem;
}