css - grunt-cssc not working "cannot read property 'type'" ~ Foundation 5 -

i having trouble using grunt-cssc in foundation 5 framework.

error:

running "cssc:build" <cssc> task warning: cannot read property 'type' of undefined use --force continue. 

my code:

cssc: {         build: {             files: {                 'css/app.css': 'css/app.css'             }         }     }, 

it conflicting libsass or else foundation side.

i solved adding options , setting "sortdeclarations", "consolidateviaselectors", "consolidatemediaqueries" false.

cssc: {         build: {             options: {                 sortselectors: true,                     linebreaks: true,                     sortdeclarations:true,                     consolidateviadeclarations:false,                     consolidateviaselectors:false,                     consolidatemediaqueries:false,             },             files: {                 'css/app.css': 'css/app.css'             }         }     },