system font stack 사용

Author: ChangJoo-Park

_sass/_variables.scss

@@ -5,7 +5,7 @@
 // Typography
 $base-font-size: 14px !default;
 $bold-font-weight: bold !default;
-$font-family: 'IropkeBatangM', 'Dotum';
+$font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Oxygen-Sans,Ubuntu,Cantarell,"Helvetica Neue",sans-serif;
 $line-height: 1.5 !default;
 $heading-font-family: 'IropkeBatangM', 'Helvetica Neue', Helvetica, sans-serif !default;
 $heading-font-weight: 900 !default;