Fix before and after selectors

sass/base/minireset.sass

@@ -53,8 +53,8 @@ html
 
 *
   &,
-  &:before,
-  &:after
+  &::before,
+  &::after
     box-sizing: inherit
 
 // Media

sass/elements/button.sass

@@ -138,7 +138,7 @@ $button-static-border-color: $grey-lighter !default
           box-shadow: none
           color: $color
       &.is-loading
-        &:after
+        &::after
           border-color: transparent transparent $color-invert $color-invert !important
       &.is-outlined
         background-color: transparent
@@ -150,7 +150,7 @@ $button-static-border-color: $grey-lighter !default
           border-color: $color
           color: $color-invert
         &.is-loading
-          &:after
+          &::after
             border-color: transparent transparent $color $color !important
         &[disabled]
           background-color: transparent
@@ -189,7 +189,7 @@ $button-static-border-color: $grey-lighter !default
   &.is-loading
     color: transparent !important
     pointer-events: none
-    &:after
+    &::after
       +loader
       +center(1em)
       position: absolute !important

sass/elements/tag.sass

@@ -82,8 +82,8 @@ $tag-delete-margin: 1px !default
     padding: 0
     position: relative
     width: 2em
-    &:before,
-    &:after
+    &::before,
+    &::after
       background-color: currentColor
       content: ""
       display: block
@@ -92,10 +92,10 @@ $tag-delete-margin: 1px !default
       top: 50%
       transform: translateX(-50%) translateY(-50%) rotate(45deg)
       transform-origin: center center
-    &:before
+    &::before
       height: 1px
       width: 50%
-    &:after
+    &::after
       height: 50%
       width: 1px
     &:hover,

sass/utilities/mixins.sass

@@ -1,7 +1,7 @@
 @import "initial-variables"
 
 =clearfix
-  &:after
+  &::after
     clear: both
     content: " "
     display: table
@@ -171,8 +171,8 @@
   position: relative
   vertical-align: top
   width: 20px
-  &:before,
-  &:after
+  &::before,
+  &::after
     background-color: $white
     content: ""
     display: block
@@ -181,10 +181,10 @@
     top: 50%
     transform: translateX(-50%) translateY(-50%) rotate(45deg)
     transform-origin: center center
-  &:before
+  &::before
     height: 2px
     width: 50%
-  &:after
+  &::after
     height: 50%
     width: 2px
   &:hover,