{#- Petrolyst: replaces Superset's empty head_custom_extra.html, which spa.html includes on every
    page (petrolyst_reader.register puts this folder first). Readers get reader.css; its address
    names its content, as browsers keep static files for a year. -#}
{% if petrolyst_is_reader() %}
  <link rel="stylesheet" href="{{ assets_prefix }}/static/assets/branding/reader.css?v={{ petrolyst_reader_css_version }}">
{% endif %}