sass - Grunt autoprefixer error when using @extent in scss file -

error:

running "autoprefixer:dist" (autoprefixer) task file .tmp/styles/documentation.css created. warning: can't parse css: missing property value @ line 66:21 in .tmp/styles/main.css use --force continue. 

line 66 points following code:

source:

span {   @extent .md-body-1; }  p {   @extent .md-body-1; } 

i can't extent tag in scss? or autoprefixer issue?

you need use @extend not @extent