wikt.css

/* standard css for master page tables */
table.master {
    width: 100%;                 /* Fill <div> */
}
table.master > tr > th,
table.master > tr > td,
table.master > * > tr > th,
table.master > * > tr > td {
    vertical-align: top;    /* Set valign variable */
}
table.master th {
    width: 28em;                 /* Set width for standard columns */
}
table.master th#thin {
    width: 20em;                 /* Set width for narrow image columns */
}

/* standard css for treatise page tables */
table.treatise th#page {
    width: 8em;                  /* Set width for page column */
}
table.treatise th#section {
    min-width: 22em;             /* Set width for section column */
}

you can get rid of the wide class and make it the default. the thin class would override.