```ruby
require 'sass'

module SCSSLint
  class Engine
    ENGINE_OPTIONS = { cache: false, syntax: :scss }

    attr_reader :contents, :tree

    def initialize(scss_or_filename)
      if File.exists?(scss_or_filename)
        @engine = Sass::Engine.for_file(scss_or_filename, ENGINE_OPTIONS)
        @contents = File.open(scss_or_filename, 'r').read
      else
        @engine = Sass::Engine.new(scss_or_filename, ENGINE_OPTIONS)
        @contents = scss_or_filename
      end

      @tree = @engine.to_tree
    end
  end
end
```

Allow access to lines of CSS file in Engine
user
```ruby
require 'sass'

module SCSSLint
  class Engine
    ENGINE_OPTIONS = { cache: false, syntax: :scss }

    attr_reader :contents, :lines, :tree

    def initialize(scss_or_filename)
      if File.exists?(scss_or_filename)
        @engine = Sass::Engine.for_file(scss_or_filename, ENGINE_OPTIONS)
        @contents = File.open(scss_or_filename, 'r').read
      else
        @engine = Sass::Engine.new(scss_or_filename, ENGINE_OPTIONS)
        @contents = scss_or_filename
      end

      @lines = @contents.split("\n")
      @tree = @engine.to_tree
    end
  end
end
```
assistant