.input-error {
    border: 2px solid red;
}

.play-grade {
    flex: 1 1 0%; 
    padding: 10px; 
    background: white; 
    color: dodgerblue; 
    border-radius: 10px; 
    border: 2px solid; 
    font-size: 2em; 
    font-weight: bold; 
    opacity: 1;
}