Custom picture element styling

Trying to apply style to a custom picture element.

- type: custom:weather-card  
            entity: weather.xxxxxxx           
            name: nnnnnnnn
            details: false
            hourly_forecast: false  
            style: |
                ha-card {
                background-color: transparent;
                font-size: 8px;
                }
              top: 25%

the font size and color portions work, but the positioning statement top: 25% does not!!