HTML and CSS: rounded corners on tables

I have a bit of a problem. I would like all corners of my table to be rounded, however the dark rows seem to still have a pointy border. Thanks for your help!

.table_background {
    display: flex;
    background-color: white;
    margin-left: 3vw;
    margin-right: 3vw;
    margin-bottom: 10vh;
    margin-top: 5vh;
    box-shadow: 0px 0px 10px rgba(114, 114, 113, 0.5);
    border-radius: 15px;
}

table {
    font-family: futura-pt, sans-serif;
    font-weight: 400;
    font-style: normal;
    border-collapse: collapse;
    width: 100%;
    border-radius: 15px;
}

th {
    font-size: 18px;
    text-align: left;
    padding: 20px 20px 20px 20px;
}

table,
td {
    padding: 8px 8px 8px 20px;
}

tr:nth-child(even) {
    background-color: #eff2f5;
}

tr:not(:first-child):hover {
    background-color: rgba(114, 114, 113, 0.2);
}

Add "overflow:hidden" on the table itself:

table {
    font-family: futura-pt, sans-serif;
    font-weight: 400;
    font-style: normal;
    border-collapse: collapse;
    width: 100%;
    border-radius: 15px;

    /* add this */
    overflow:hidden
}