Me aumenta las fuentes, por qué???

[una_xikilla]

.tituloRegistro {
font-family: Arial, Helvetica, sans-serif;
font-size: large;
font-style: italic;
font-weight: bold;
line-height: normal;
font-variant: normal;
color: #FF0000;
}
.TextoNormal {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: small;
color: #000000;
font-weight: bold;
}
.FuenteRegistro {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: small;
font-style: italic;
font-weight: bold;
color: #000080;
}