fix button dropdown whitespace issue in safari

Author: sesemaya

assets/sass/components/_dropdown.scss

@@ -89,6 +89,8 @@
 	}
 
 .dropdown-toggle-btn {
+	margin-right: 1px;
+	margin-left: 1px;
 	padding-right: $grid-gutter;
 	padding-left: $grid-gutter;
 	position: relative;
@@ -99,18 +101,17 @@
 		color: $black-text;
 	}
 	~ .dropdown-menu {
-		min-width: 101%;
-		min-width: calc(100% + 2px);
+		min-width: 100%;
 		padding-top: ($btn-height + $margin-base + ($nav-height - $btn-height)) !important;
 		// position
 			top: ($margin-base * -1 + ($nav-height - $btn-height) / -2);
-			left: -1px;
+			left: 0;
 		transform: scale(1, 0);
 		&.dropdown-menu-right,
 		.dropdown.pull-right &,
 		.nav.pull-right & {
 			// position
-				right: -1px;
+				right: 0;
 				left: auto;
 		}
 	}

css/base.css

@@ -5923,6 +5923,8 @@ pre code {
 }
 
 .dropdown-toggle-btn {
+  margin-right: 1px;
+  margin-left: 1px;
   padding-right: 16px;
   padding-left: 16px;
   position: relative;
@@ -5934,18 +5936,16 @@ pre code {
   color: #212121;
 }
 .dropdown-toggle-btn ~ .dropdown-menu {
-  min-width: 101%;
-  min-width: -webkit-calc(100% + 2px);
-  min-width: calc(100% + 2px);
+  min-width: 100%;
   padding-top: 56px !important;
   top: -14px;
-  left: -1px;
+  left: 0;
   -webkit-transform: scale(1, 0);
       -ms-transform: scale(1, 0);
           transform: scale(1, 0);
 }
 .dropdown-toggle-btn ~ .dropdown-menu.dropdown-menu-right, .dropdown.pull-right .dropdown-toggle-btn ~ .dropdown-menu, .nav.pull-right .dropdown-toggle-btn ~ .dropdown-menu {
-  right: -1px;
+  right: 0;
   left: auto;
 }