bring back checkbox borders to iOS by conditionalizing the border: 0; on it to IE7-9; fix word break on pre in IE

less/code.less

@@ -34,6 +34,7 @@ pre {
   white-space: pre;
   white-space: pre-wrap;
   word-break: break-all;
+  word-wrap: break-word;
 
   // Make prettyprint styles more spaced out for readability
   &.prettyprint {

less/forms.less

@@ -96,9 +96,12 @@ input[type="radio"] {
   margin: 3px 0;
   *margin-top: 0; /* IE7 */
   line-height: normal;
-  border: 0;
   cursor: pointer;
   .border-radius(0);
+  border: 0 \9; /* IE9 and down */
+}
+input[type="image"] {
+  border: 0;
 }
 
 // Reset the file input to browser defaults