Sass not compiling after buying ionsocialapp theme

HI, I just purchased the theme and after running
1 - npm install -g cordova
2 - npm install -g ionic
3 - npm install
4 - bower install
5 - ionic setup sass or gulp

I got a sass compilation error as below :
Can someone explain to me why this happen and how to fix it ? Thanks

events.js:160
throw er; // Unhandled ‘error’ event
^
Error: scss/utils/mixins.scss
Error: Invalid CSS after “…$placeholders {”: expected “}”, was "&: #{$placeholder}-"
on line 26 of scss/utils/mixins.scss
@each $placeholder in $placeholders {
---------------------------------------^
at options.error (/Users/stephane/Desktop/ionsocialapp/node_modules/node-sass/lib/index.js:286:26)

Caught exception:
TypeError: Cannot read property ‘bold’ of undefined
at ChildProcess. (/usr/local/lib/node_modules/ionic/node_modules/ionic-app-lib/lib/setup.js:152:38)
at emitTwo (events.js:106:13)
at ChildProcess.emit (events.js:191:7)
at Process.ChildProcess._handle.onexit (internal/child_process.js:215:12)