few improvements for some <select> elements

src/sass/components/_buttons.scss

@@ -142,6 +142,10 @@ form[action*="repository/diff"] {
  */
 
 .query-columns {
+    select {
+        width: auto !important;
+    }
+
     .buttons {
         vertical-align: middle;
 

src/sass/components/_forms.scss

@@ -101,8 +101,13 @@ select {
         height: auto;
     }
 
-    option[disabled] {
-        color: $gray-lighter;
+    option {
+        padding-right: $input-padding-horizontal;
+        padding-left: $input-padding-horizontal;
+
+        &[disabled] {
+            color: $gray-lighter;
+        }
     }
 }
 

src/sass/components/_top.scss

@@ -103,6 +103,15 @@
         }
     }
 
+    option {
+        background-color: $input-bg;
+        color: $input-color;
+
+        &[disabled] {
+            color: $gray-lighter;
+        }
+    }
+
     input {
         width: 200px;
     }