Tiny CSS tweaks.

misago/static/misago/css/misago/variables.less

@@ -99,9 +99,9 @@
 
 
 // Guest Sign in button
-@btn-sign-in-color:                    fadeOut(@brand-primary, 30%);
+@btn-sign-in-color:                    @brand-primary;
 @btn-sign-in-bg:                       @navbar-default-bg;
-@btn-sign-in-border:                   fadeOut(@brand-primary, 30%);
+@btn-sign-in-border:                   transparent;
 
 @btn-sign-in-hover-color:              @brand-primary;
 @btn-sign-in-hover-bg:                 fadeOut(@brand-primary, 90%);