iFrame in picture-elements panel view?

Hi, just need some help for a noob.
I tried to use the custom-iframe card as explained in lukevink Github and also jparthum but I got always the same message on mi picture-card–> Custom element doesn’t exist: custom-iframe.
This is what I’ve done:
1.-Download and copy custom-iframe-card.js into /www/js (also tried copying in www, also in the same dir as my ui-lovelace.yaml)
2.- Edit my ui-lovelace.yaml and add js as a resource
3.- Add to my card (inside ui-lovelace.yaml) the custom-iframe
But… no result at all, All I got is a big red frame with the msg … custom-iframe doesn’t exist
Here is my code. (ui-lovelace.yaml)
Identation should not be the problem (no errors at editor)

title: home
panel: true
resources:
  - type: js
    url: /local/js/custom-iframe-card.js    
views:
  - title: Salón
    badges: []
    path: Salon
    panel: true
    icon: 'mdi:home-floor-0'
    cards:
      
      - type: picture-elements
        image: /local/salon_off_0.png
        elements:
          - type: 'custom:custom-iframe'
            url: www.google.es
            style:
              left: 50%
              top: 50%
              width: 50%
              height: 50%         

Any suggestion/help/clue would be really appreciated!!
Thanks in advance for your time!!