diff --git a/vendor/assets/stylesheets/bootstrap/mixins.css.scss b/vendor/assets/stylesheets/bootstrap/mixins.css.scss
index 5b6a1e4d..054b2dee 100644
--- a/vendor/assets/stylesheets/bootstrap/mixins.css.scss
+++ b/vendor/assets/stylesheets/bootstrap/mixins.css.scss
@@ -166,7 +166,7 @@
   background-image: -webkit-linear-gradient(left, $startColor, $endColor); // Safari 5.1+, Chrome 10+
   background-image: -o-linear-gradient(left, $startColor, $endColor); // Opera 11.10
   background-image: linear-gradient(left, $startColor, $endColor); // Le standard
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($startColor)}', endColorstr='#{ie-hex-str($endColor)}', GradientType=1); // IE9 and down
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie_hex_str($startColor)}', endColorstr='#{ie_hex_str($endColor)}', GradientType=1); // IE9 and down
 }
 @mixin vertical-gradient($startColor: #555, $endColor: #333) {
   background-color: $endColor;
@@ -178,7 +178,7 @@
   background-image: -webkit-linear-gradient(top, $startColor, $endColor); // Safari 5.1+, Chrome 10+
   background-image: -o-linear-gradient(top, $startColor, $endColor); // Opera 11.10
   background-image: linear-gradient(top, $startColor, $endColor); // The standard
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($startColor)}', endColorstr='#{ie-hex-str($endColor)}', GradientType=0); // IE9 and down
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie_hex_str($startColor)}', endColorstr='#{ie_hex_str($endColor)}', GradientType=0); // IE9 and down
 }
 @mixin directional-gradient($startColor: #555, $endColor: #333, $deg: 45deg) {
   background-color: $endColor;
@@ -198,7 +198,7 @@
   background-image: -ms-linear-gradient($startColor, $midColor $colorStop, $endColor);
   background-image: -o-linear-gradient($startColor, $midColor $colorStop, $endColor);
   background-image: linear-gradient($startColor, $midColor $colorStop, $endColor);
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($startColor)}', endColorstr='#{ie-hex-str($endColor)}', GradientType=0); // IE9 and down, gets no color-stop at all for proper fallback
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie_hex_str($startColor)}', endColorstr='#{ie_hex_str($endColor)}', GradientType=0); // IE9 and down, gets no color-stop at all for proper fallback
 }
 
 // Reset filters for IE