You can do this by using CSS override, for example, you can use CSS code below
.archive .sps-swatches { overflow: hidden; max-width: 230px; max-height: 42px; }
Important Notice: The values of max-width and max-height will depend on your WP Theme and your swatch size settings.
To center the swatches, you can use CSS override code below
.archive .sps-swatches { text-align: center; }