Declare a local variable at the beginning of the View:
@{
   var yourStyle = "";
   if(Model.Condition)
   {
       yourStyle = "float:left;";
       //specific conditions and logic
   }
   else
   {
       yourStyle = "float:right;";
      //any other conditions and logic
   }
}
and then just use it in your div:
<div style="@yourStyle">
	