Lo aprendido

Tabla

<table>
            <thead>
                <tr>
                    <th>Día</th>
                    <th>Horario</th>
                </tr>
            </thead>

            <tbody>
                <tr>
                    <td>Lunes</td>
                    <td>08h-20h</td>
                </tr>
                <tr>
                    <td>Miercoles</td>
                    <td>08h-20h</td>
                </tr>
                <tr>
                    <td>Viernes</td>
                    <td>08h-20h</td>
                </tr>
            </tbody>

        </table>

Styles.css

table {
    margin: 40px 40px;

}

thead {
    background: #555555;
    color: #FFF;
    font-weight: bold;
}

td,
th {
    border: 1px solid #000;
    padding: 8px 15px;
}