Add example of a Spanish translation for custom file input (#25302)

mdo · XhmikosR · commit fa3de5cbd8f7 · 2018-01-15T09:19:12.000+02:00
diff --git a/assets/scss/_component-examples.scss b/assets/scss/_component-examples.scss
@@ -147,6 +147,10 @@
     }
   }
 
+  .custom-file-input:lang(es) ~ .custom-file-label::after {
+    content: "Elegir";
+  }
+
   > .form-control {
     + .form-control {
       margin-top: .5rem;
diff --git a/docs/4.0/components/forms.md b/docs/4.0/components/forms.md
@@ -1162,8 +1162,17 @@ The [`:lang()` pseudo-class](https://developer.mozilla.org/en-US/docs/Web/CSS/:l
 {% highlight scss %}
 $custom-file-text: (
   en: "Browse",
-  es: "Navegar"
+  es: "Elegir"
 );
 {% endhighlight %}
 
+Here's `lang(es)` in action on the custom file input for a Spanish translation:
+
+{% example html %}
+<div class="custom-file">
+  <input type="file" class="custom-file-input" id="customFileLang" lang="es">
+  <label class="custom-file-label" for="customFileLang">Seleccionar Archivo</label>
+</div>
+{% endexample %}
+
 You'll need to set the language of your document (or subtree thereof) correctly in order for the correct text to be shown. This can be done using [the `lang` attribute](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/lang) on the `<html>` element or the [`Content-Language` HTTP header](https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.12), among other methods.

Original file line number	Diff line number	Diff line change
`@@ -147,6 +147,10 @@`
`147`	`147`	`}`
`148`	`148`	`}`
`149`	`149`
	`150`	`+ .custom-file-input:lang(es) ~ .custom-file-label::after {`
	`151`	`+ content: "Elegir";`
	`152`	`+ }`
	`153`	`+`
`150`	`154`	`> .form-control {`
`151`	`155`	`+ .form-control {`
`152`	`156`	`margin-top: .5rem;`