7.0.28 introduced regression to `hc-light.scss` that causes compilation failure on `make css`:

{{sass --no-cache --sourcemap=none sass/stylesheets/sass/screen.scss ui/assets/styles/blue-theme.css  
sass --no-cache --sourcemap=none sass/stylesheets/sass/dark-theme.scss ui/assets/styles/dark-theme.css  
sass --no-cache --sourcemap=none sass/stylesheets/sass/hc-light.scss ui/assets/styles/hc-light.css  
Error: Invalid CSS after "...erity-icon-na: ": expected "}", was "url("data:image..."  
       on line 2 of sass/stylesheets/sass/base/_icons-severity.scss  
       from line 218 of sass/stylesheets/sass/hc-light.scss

}}

Unfortunately this is not a pedantic/cosmetic issue: on Debian we re-build .CSS files from source and FTBFS like this prevents upload of Zabbix higher than 7.0.27 (with all security/CVE fixes)...