JSFiddle - React, Tailwind, and code Playground

HTML

<table class="calendar_table">
<tr>
        <td>
            <h2>Datum</h2>
        </td>
        <td>
            <h2>Event</h2>
        </td>
        <td>
            <h2>Type</h2>
        </td>
    </tr>
</table>

CSS

.calendar_table {
    width:880px;
}
.calendar_table tr {
    margin:0;
    padding:4px;
}
table {
    border: 1px solid black;
}