* {
  margin: 0;
  padding: 0;
}
.stud_info {
  width: 800px;
  height: 500px;
  /* background-color: pink; */
  margin: 50px auto;
  text-align: center;
}
.stud_info, th, tr, td {
  border: 1px solid;
  border-collapse: collapse;
}
.stud_info caption {
  font-size: 23px;
  font-weight: 700;
  margin-bottom: 10px;
}
.stud_info th {
  height: 30px;;
}
.stud_info tr:nth-child(2n) {
  background-color: lightblue;
}