Making button shadow look more like lovelace-soft-ui

[misadeks]

How is it possible to achieve having the same element shadows as the Lovelace Soft UI, which uses this style snippet:

style: |
  ha-card {
      background-color: var(--primary-background-color);
      border-radius: 15px;
      margin: 10px;
      box-shadow: 
        {% if is_state('sun.sun', 'above_horizon') %}
          -8px -8px 8px 0 rgba(255,255,255,.5),8px 8px 8px 0 rgba(0,0,0,.03);
        {% else %}
          -8px -8px 8px 0 rgba(50, 50, 50,.5),8px 8px 8px 0 rgba(0,0,0,.15);
        {% endif %}   
   }