.bookshelf {
  padding: 20px;
  background-color: #fff;
  border-radius: 5px;
  box-shadow: 0 0 5px #333;
}
.bookshelf-title {
  color: #007fff;
  font-size: 18px;
  position: relative;
}
.bookshelf-title::before,
.bookshelf-title::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -10px;
  transform: translateY(-50%) scale(0.999);
  display: inline-block;
  width: 22%;
  height: 1px;
  background-color: #007fff;
  animation: aWidth 1.2s infinite linear;
}
.bookshelf-title::after {
  bottom: -15px;
  animation-delay: 0.25s;
}
@-moz-keyframes aWidth {
  0% {
    width: 22%;
  }
  25% {
    width: 36%;
  }
  50% {
    width: 20%;
  }
  75% {
    width: 30%;
  }
  100% {
    width: 22%;
  }
}
@-webkit-keyframes aWidth {
  0% {
    width: 22%;
  }
  25% {
    width: 36%;
  }
  50% {
    width: 20%;
  }
  75% {
    width: 30%;
  }
  100% {
    width: 22%;
  }
}
@-o-keyframes aWidth {
  0% {
    width: 22%;
  }
  25% {
    width: 36%;
  }
  50% {
    width: 20%;
  }
  75% {
    width: 30%;
  }
  100% {
    width: 22%;
  }
}
@keyframes aWidth {
  0% {
    width: 22%;
  }
  25% {
    width: 36%;
  }
  50% {
    width: 20%;
  }
  75% {
    width: 30%;
  }
  100% {
    width: 22%;
  }
}
.bookshelf-empty {
  margin-top: 20px;
  padding: 40px 0;
  text-align: center;
  color: #999;
  font-size: 14px;
}
.bookshelf-list {
  display: flex;
  flex-wrap: wrap;
  margin-top: 20px;
}
.bookshelf-item {
  width: 130px;
  margin: 0 15px 20px 0;
}
.bookshelf-item a {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.bookshelf-item .book-cover {
  width: 120px;
  height: 160px;
  object-fit: cover;
  border-radius: 3px;
  box-shadow: 3px 3px 8px rgba(0,0,0,0.25);
  transition: transform 0.3s, box-shadow 0.3s;
}
.bookshelf-item .book-info {
  margin-top: 10px;
  text-align: center;
}
.bookshelf-item .book-title {
  font-size: 14px;
  color: #333;
  font-weight: bold;
  transition: color 0.3s;
}
.bookshelf-item .book-author {
  margin-top: 4px;
  font-size: 12px;
  color: #999;
}
.bookshelf-item:hover .book-cover {
  transform: translateY(-6px) rotate(-2deg);
  box-shadow: 5px 8px 14px rgba(0,0,0,0.35);
}
.bookshelf-item:hover .book-title {
  color: #007fff;
}