trying to turn %button.twitter-button.btn.btn-inverse into an anchor link

I tried this

= provide(:css_class, "landing")

.row-fluid
  .span12
    .banner
      %section.main
        %h1{:class => "depth", :title => "Ruby on Rails Theme Marketplace"}
          Ruby on Rails Themes
        .sub-header
          %h2 Open Marketplace
          %a{:class => "twitter-button btn btn-inverse", :href => ""}
        %p
          Railsview is your one-stop marketplace for buying and selling custom themes for Rails applications. Streamline your development process with a high quality design, fully customizable to your project needs. Get your app rolling today!
      %section.sidebar
        = link_to "Get Started", get_started_path, {:class => "btn btn-xlarge btn-info"}
.row-fluid
  .span12.controls
    = form_tag(root_path, method: :get, id: :filters) do
      = select_tag "filter", options_for_select(["all", "free", "popular", "price"], params[:filter]), :class => "filter-select"
      %span.sort
        = label_tag nil, class: "filter-ascending" do
          = radio_button_tag :order, 'asc', params[:order] == 'asc' || params[:order].blank?
          %span
            ASC
        = label_tag nil, class: "filter-descending" do
          = radio_button_tag :order, 'desc', params[:order] == 'desc'
          %span
            DESC
      = submit_tag "Filter", name: nil

    = image_tag "filter-none.png", :class => "nofilter"
    #paginator= paginate @themes, remote: true, params: {}
#themes
  .page
    = render "themes"

original

= provide(:css_class, "landing")

.row-fluid
  .span12
    .banner
      %section.main
        %h1{:class => "depth", :title => "Ruby on Rails Theme Marketplace"}
          Ruby on Rails Themes
        .sub-header
          %h2 Open Marketplace
          %button.twitter-button.btn.btn-inverse
        %p
          Railsview is your one-stop marketplace for buying and selling custom themes for Rails applications. Streamline your development process with a high quality design, fully customizable to your project needs. Get your app rolling today!
      %section.sidebar
        = link_to "Get Started", get_started_path, {:class => "btn btn-xlarge btn-info"}
.row-fluid
  .span12.controls
    = form_tag(root_path, method: :get, id: :filters) do
      = select_tag "filter", options_for_select(["all", "free", "popular", "price"], params[:filter]), :class => "filter-select"
      %span.sort
        = label_tag nil, class: "filter-ascending" do
          = radio_button_tag :order, 'asc', params[:order] == 'asc' || params[:order].blank?
          %span
            ASC
        = label_tag nil, class: "filter-descending" do
          = radio_button_tag :order, 'desc', params[:order] == 'desc'
          %span
            DESC
      = submit_tag "Filter", name: nil

    = image_tag "filter-none.png", :class => "nofilter"
    #paginator= paginate @themes, remote: true, params: {}
#themes
  .page
    = render "themes"