.testavailability {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-flow: row wrap;
    border: 1px solid black;
    padding: 20px;
}

.testheader,
.testblock {
    width: 100%;
    height: 40px;
    display: grid;
    grid-template-columns: 300px 200px 1fr;
    grid-template-rows: 1fr;
    grid-column-gap: 20px;
    align-items: center;
}

.testheader {
    font-weight: bold;
}