fix: make the submit field more visible

hiboo/templates/macros.html

@@ -119,7 +119,7 @@
 
 {% macro form_field(field) %}
   {% if field.type == 'SubmitField' %}
-  {{ form_fields((field,), label=False, class="btn btn-default", **kwargs) }}
+  {{ form_fields((field,), label=False, class="btn btn-info", **kwargs) }}
   {% elif field.type not in ('HiddenField', 'CSRFTokenField') %}
   {{ form_fields((field,), **kwargs) }}
   {% endif %}