.toefl-insert-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    aspect-ratio: 1.1;
    font-size: x-small;
    line-height: 0.7;
    vertical-align: middle;
    background: #333;
    cursor: pointer;
    padding: 0;
    color:white;
    border: 1px solid black;
    border-radius:3px;
    padding:3px;
    margin-right: 4px; 
}
.mark-v {
    background-color: #aaddff;  
}
.mark-r {
    background-color: #ffaadd;
}