Это сработало для меня:
<style>
.v-text-field .v-input__control .v-input__slot {
min-height: 30px;
}
.v-text-field.v-text-field--enclosed .v-input__prepend-outer, .v-text-field
.v-text-field--enclosed .v-input__prepend-inner, .v-text-field.v-text-field--enclosed
.v-input__append-inner, .v-text-field.v-text-field--enclosed .v-input__append-outer {
margin-top: 5px;
}
</style>