* {
  margin: 0;
  padding: 0;

}

table {
  margin: 20px auto;
  border-collapse: collapse;
  /*将单元格之间的空隙删除掉*/

}

tr,
td {
  width: 120px;
  height: 50px;
  border: 1px solid #000;
  text-align: center;
  font-size: 18px;
}

.header {
  background-color: rgb(247, 246, 247);
}

.btn,
.bookname {
  width: 210px;
}

button {
  width: 50px;
  height: 30px;
  border: 1px solid greenyellow;
  color: #fff;
  background-color: green;
}

h2 {
  text-align: center;
  margin: 20px;
}

.counts>button {
  width: 20px;
  height: 20px;
  background-color: gray;
  border: #fff;
  border-radius: 5px;
}