Cross-browser compatible styling for input[type=file] (publiclab#5424)

* Apply styling

* Add comments

app/assets/stylesheets/application.css

@@ -11,12 +11,13 @@
  * If there are other assets (which are not in this file) that are being precompiled by
  * 'stylesheet_link_tag' command in views, then add them on /config/initializers/assets.rb
 
-
+ 
  *= require bootstrap/dist/css/bootstrap.min.css
  *= require bootstrap-datepicker/dist/css/bootstrap-datepicker3.css
  *= require jquery-file-upload/css/jquery.fileupload-ui.css
  *= require leaflet/dist/leaflet.css
  *= require_self
+ *= require cross_browser
  *= require style
  *= require feature
  *= require btsp_checkbox_override

app/assets/stylesheets/cross_browser.css

@@ -0,0 +1,14 @@
+/* 
+================================================================
+We can start using this file to document and fix all cross-browser inconsistencies 
+we find in one place 
+================================================================
+*/
+
+
+/* Firefox ignores line-height for input[type="file"] but Chrome doesn't and the result
+with Bootstrap styling is it gets misaligned in Chrome. This fix is confirmed to create 
+compatible alignment in Chrome, Safari, and Firefox in MacOS */ 
+input[type="file"] {
+  line-height: 0 !important;
+}