Default theme to light

Signed-off-by: Jason Cameron <[email protected]>

judge/template_context.py

@@ -82,16 +82,20 @@ def site_name(request):
 
 def site_theme(request):
     # Middleware populating `profile` may not have loaded at this point if we're called from an error context.
+    if hasattr(request.user, 'profile'):
+        preferred_css = settings.DMOJ_THEME_CSS.get(request.profile.site_theme, settings.DMOJ_THEME_CSS['light'])
+    else:
+        preferred_css = None
     return {
         'DARK_STYLE_CSS': settings.DMOJ_THEME_CSS['dark'],
         'LIGHT_STYLE_CSS': settings.DMOJ_THEME_CSS['light'],
-        'PREFERRED_STYLE_CSS': settings.DMOJ_THEME_CSS['dark'],
+        'PREFERRED_STYLE_CSS': preferred_css,
     }
 
 
 def math_setting(request):
     caniuse = CanIUse(request.META.get('HTTP_USER_AGENT', ''))
-
+    
     # Middleware populating `profile` may not have loaded at this point if we're called from an error context.
     if hasattr(request.user, 'profile'):
         engine = request.profile.math_engine