.teachingschedule tr {
   border-bottom: 1px solid black;  
   
}

.teachingschedule table {
    border: 1px solid black;
}

.teachingschedule tr:nth-child(even) {
    background-color: #f2f2f2;
}

.teachingschedule tr:nth-child(even):hover {
    background-color: #afa;
}

.teachingschedule tr:nth-child(odd):hover {
    background-color: #afa;
}

.teachingschedule {
    margin: auto;
    display: block;
    max-width: 700px;
}