<table> <tr> <th>Mamíferos</th> <th>Aves</th><th>Peces</th><th>Reptiles</th> </tr> <tr> <td>Gato</td><td>Gallo</td><td>Salmón</td> <td>Caimán</td> </tr> <tr> <td>Perro</td><td>Colibrí</td><td>Sierra</td> <td>Salamandra</td> </tr> <tr> <td>León</td><td>Paloma</td><td>Atún</td><td>Boa</td> </tr> </table> table, th, td { border: 2px solid black; border-collapse: collapse; text-align: left; } table { width:60%; } th, td { padding: 2px 10px 2px 10px; } th { background: rgb(79,112,197); color: white; } tr:nth-child(even) {background-color: #d2e2d2;}