class Sass::Tree::PropNode

def val_to_sass_div(node, opts)
  unless node.is_a?(Sass::Script::Tree::Operation) && node.operator == :div &&
      node.operand1.is_a?(Sass::Script::Tree::Literal) &&
      node.operand1.value.is_a?(Sass::Script::Value::Number) &&
      node.operand2.is_a?(Sass::Script::Tree::Literal) &&
      node.operand2.value.is_a?(Sass::Script::Value::Number) &&
      (!node.operand1.value.original || !node.operand2.value.original)
    return node
  end
  Sass::Script::Value::String.new("(#{node.to_sass(opts)})")
end