/*
Error: Undefined mixin 'box'.
        on line 4 of src/public/scss/footer.scss, in `box'
        from line 4 of src/public/scss/footer.scss

1: footer{
2:     position: absolute;
3:     bottom: 0;
4:     @include  box(100vw, 10vh);
5:     div.introduction{
6:         border-radius: 30px;
7:         @include posCenter(7vw, 4.5vh);
8:         @include box(14vw, 9vh);
9:         display: flex;

Backtrace:
src/public/scss/footer.scss:4:in `box'
src/public/scss/footer.scss:4
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:348:in `block in visit_mixin'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:98:in `block in with_mixin'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:135:in `with_frame'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:98:in `with_mixin'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:346:in `visit_mixin'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:36:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:79:in `block in with_base'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:135:in `with_frame'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:79:in `with_base'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:158:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:440:in `block (2 levels) in visit_rule'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:440:in `map'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:440:in `block in visit_rule'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:438:in `visit_rule'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:36:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:79:in `block in with_base'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:135:in `with_frame'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/stack.rb:79:in `with_base'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:158:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:52:in `block in visit_children'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:52:in `map'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:52:in `visit_children'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:167:in `block in visit_children'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:166:in `visit_children'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:36:in `block in visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:186:in `visit_root'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/base.rb:36:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:157:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/visitors/perform.rb:10:in `visit'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/root_node.rb:36:in `css_tree'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/tree/root_node.rb:29:in `render_with_sourcemap'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/engine.rb:389:in `_render_with_sourcemap'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/engine.rb:307:in `render_with_sourcemap'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:462:in `update_stylesheet'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:215:in `block in update_stylesheets'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:209:in `each'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:209:in `update_stylesheets'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:443:in `on_file_changed'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-3.6.0/lib/sass/plugin/compiler.rb:320:in `block in watch'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/config.rb:23:in `call'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/processor.rb:115:in `_process_changes'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/processor.rb:19:in `block in loop_for'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/processor.rb:15:in `loop'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/processor.rb:15:in `loop_for'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/loop.rb:84:in `_wait_for_changes'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/event/loop.rb:42:in `block in setup'
D:/Programer/Ruby25-x64/lib/ruby/gems/2.5.0/gems/sass-listen-4.0.0/lib/sass-listen/internals/thread_pool.rb:6:in `block in add'
*/
body:before {
  white-space: pre;
  font-family: monospace;
  content: "Error: Undefined mixin 'box'.\A         on line 4 of src/public/scss/footer.scss, in `box'\A         from line 4 of src/public/scss/footer.scss\A \A 1: footer{\A 2:     position: absolute;\A 3:     bottom: 0;\A 4:     @include  box(100vw, 10vh);\A 5:     div.introduction{\A 6:         border-radius: 30px;\A 7:         @include posCenter(7vw, 4.5vh);\A 8:         @include box(14vw, 9vh);\A 9:         display: flex;"; }