Pull in a custom value based on what page you are on.

page_param-rails.rb

<% page_name = params[:page] ? "video_url_#{params[:page]}".to_sym : :video_url %>
  <% if @client.stores.first.send(page_name).present? && @client.stores.first.send(page_name) %>
    <li class="btn video-btn"><%= link_to "WATCH OUR VIDEO<span class='cta-bottom-icon'>#{image_tag('cta_video_arrow.png')}</span>".html_safe, @client.stores.first.send(page_name), :class => "video", :rel => "shadowbox;height=550;width=600;" %>
    </li>
  <% elsif @client.stores.first.video_url %>
    <li class="btn video-btn"><%= link_to "WATCH OUR VIDEO<span class='cta-bottom-icon'>#{image_tag('cta_video_arrow.png')}</span>".html_safe, @client.stores.first.video_url, :class => "video", :rel => "shadowbox;height=550;width=600;" %>
    </li>
<% end -%>