fixes #3384: add support for multiple inputs per line when using grid sizing

less/forms.less

@@ -290,8 +290,18 @@ textarea[class*="span"],
 // GRID SIZING FOR INPUTS
 // ----------------------
 
+// Grid sizes
 #grid > .input(@gridColumnWidth, @gridGutterWidth);
 
+// Control row for multiple inputs per line
+.controls-row {
+  .clearfix(); // Clear the float from controls
+}
+.controls-row [class*="span"] {
+  float: left; // Float to collapse white-space for proper grid alignment
+}
+
+
 
 
 // DISABLED STATE

less/mixins.less

@@ -721,6 +721,11 @@
       margin-left: 0; // override margin-left from core grid system
     }
 
+    // Space grid-sized controls properly if multiple per line
+    .controls-row [class*="span"] + [class*="span"] {
+      margin-left: @gridGutterWidth;
+    }
+
     // generate .spanX
     .spanX (@gridColumns);