Changing the basemap style

<MapLibre {style} class={mapClasses} standardControls center={[-98.137, 40.137]} zoom={4}>
  <GeoJSON id="states" data={dataset} promoteId="STATEFP">
    {#if showFill}
      <FillLayer
        paint={{
          'fill-color': fillColor,
          'fill-opacity': 0.5,
        }}
        beforeLayerType="symbol"
      />
    {/if}
    {#if showBorder}
      <LineLayer
        layout={{ 'line-cap': 'round', 'line-join': 'round' }}
        paint={{ 'line-color': borderColor, 'line-width': 3 }}
        beforeLayerType="symbol"
      />
    {/if}
  </GeoJSON>
</MapLibre>