allow more than two columns in horizontal form

app/assets/stylesheets/bootstrap_and_overrides.css.less

@@ -248,17 +248,21 @@ tr.unavailable {
   margin: 0;
 }
 
-// two-column layout in forms (landscape tablet and wider only)
+// multiple-column layout in forms (landscape tablet and wider only)
 @media (min-width: 768px) {
-  .form-horizontal .twocol {
-    .control-group:nth-child(odd) {
+  .form-horizontal .fold-line {
+    .control-group {
       float: left;
     }
-    .control-group:nth-child(even) {
+    .control-group + .control-group {
       .control-label {
         width: auto;
         margin: 0 10px;
       }
+      .controls {
+        float: left;
+        margin-left: 0;
+      }
       // fix margin somehow off
       // XXX there must be a better way
       margin-bottom: 0;
@@ -267,6 +271,12 @@ tr.unavailable {
         margin-bottom: 20px;
       }
     }
+    .control-group:last-child {
+      float: none;
+      .controls {
+        float: none;
+      }
+    }
   }
 }
 // allow to have indicator text instead of input with same markup

app/views/articles/_form.html.haml

@@ -7,7 +7,7 @@
   .modal-body
     = f.input :availability
     = f.input :name
-    .twocol
+    .fold-line
       = f.input :unit_quantity, label: Article.human_attribute_name(:unit),
           input_html: {class: 'input-mini', title: Article.human_attribute_name(:unit_quantity)}
       = f.input :unit, label: '×'.html_safe,
@@ -17,7 +17,7 @@
     = f.association :article_category
     / TODO labels
 
-    .twocol
+    .fold-line
       = f.input :price do
         .input-prepend
           %span.add-on= t 'number.currency.format.unit'
@@ -26,6 +26,7 @@
         .input-append
           = f.input_field :tax, class: 'input-mini'
           %span.add-on %
+    .fold-line
       = f.input :deposit do
         .input-prepend
           %span.add-on= t 'number.currency.format.unit'