def get_style_var(var_name)
      style_details = style_variables_for_theme["vic"] || Pwb::PresetStyle.default_values
      style_vars = style_details["variables"] || []
      style_vars[var_name] || ""
    end
def get_style_var(var_name)
      style_details = style_variables_for_theme["vic"] || Pwb::PresetStyle.default_values
      style_vars = style_details["variables"] || []
      style_vars[var_name] || ""
    end
below used by custom stylesheet generator to decide
 values for various class names (mainly colors)