ui <- fluidPage(

  title="Football league competitiveness and countries European performance",lang="en",

  theme="css.css",
  useShinyjs(),
  tags$head(
    tags$script(HTML("
      Shiny.addCustomMessageHandler('bindModalHidden', function(message) {
        $('#shiny-modal').off('hidden.bs.modal.modalListener');
        $('#shiny-modal').on('hidden.bs.modal.modalListener', function () {
          Shiny.setInputValue('modal_closed_nonce', Math.random(), {priority: 'event'});
        });
      });
    "),
    "function sendWidth() {
      Shiny.setInputValue('screen_width', window.innerWidth);
    }
    $(document).on('shiny:connected', sendWidth);
    $(window).on('resize', sendWidth);"),
    tags$style(
      # the create_scrolly_side will return a list, the first object is the CSS classes that create the stick position scrolling behaviour.
      # the second object is the javascript that links the scrolling to change CSS classes and update shiny inputs (loaded at end of page)
      
      HTML(as.character(create_scrolly_side("time_plot")[1])),
      HTML(as.character(create_scrolly_side("league_averages_plot")[1])),
      HTML(as.character(create_scrolly_side("basic_profiling_plot")[1])),
      HTML(as.character(create_scrolly_side("regression_current_year_plot")[1])),
      HTML(as.character(create_scrolly_side("regression_next_year_plot")[1])),
      HTML(as.character(create_scrolly_side("regression_competition_plot")[1])),
      HTML(as.character(create_scrolly_side("clustering_plot")[1]))
    ),
    
    HTML(
      "<meta name=\"viewport\" content=\"width=device-width,initial-scale=1\">
<meta property=\"og:title\" content=\"Football league competitiveness and countries European performance\">
<meta property=\"og:description\" content=\"Football league competitiveness and countries European performance\">"
      )
  ),
  
  #### header ####
  div(class = "header",
      tags$div(
        style = "display: flex; flex-direction: column;",
        tags$a(`aria-label` = "Jump back to contents", href = "#contents", class = "jump-link", "Jump back to contents")
      )
  ),
  
  #### title and contents ####
  
  div(id = "contents", class = "toc",
      tags$h1(title),
      tags$a(href = "https://youtu.be/_mnsaDJzpso?si=3EnfpdRqXp4afBiI", tags$strong("Click here for a link to a static version of the report")),
      p(style = 'font-weight: bold; text-align: right; font-size: 1.2em;', "Scroll to begin  ▼"),
      tags$h3("Table of Contents"),
      tags$ul(
        tags$li(tags$a(href = "#motivation", tags$strong("Motivation"))),
        tags$li(tags$a(href = "#exploratory_analysis", tags$strong("Exploratory analysis"))),
        tags$ul(
          tags$li(tags$a(href = "#time_plot", "Europe's top 6 leagues European performance since 1999-2000")),
          tags$li(tags$a(href = "#variable_selection", "Variables used in analysis of leagues competitiveness")),
          tags$li(tags$a(href = "#league_averages_plot", "Characteristics of leagues since 1999-2000")),
          tags$li(tags$a(href = "#basic_profiling", "Characteristics of leagues grouped by performance"))
          ),
        tags$li(tags$a(href = "#modelling", tags$strong("Modelling"))),
        tags$ul(
                tags$li(tags$a(href = "#variable_creation", tags$strong("Variable creation"))),
                tags$li(tags$a(href = "#regression", tags$strong("Regression analysis"))),
                tags$ul(
                  tags$li(tags$a(href = "#regression_current_year", "On league characteristics and same season's European performance")),
                  tags$li(tags$a(href = "#regression_next_year", "On league characteristics and next season's European performance")),
                  tags$li(tags$a(href = "#regression_competition", "On league characteristics and same season's European performance by competition"))
                ),
                tags$li(tags$a(href = "#clustering", tags$strong("Clustering to group similar seasons together")))
        ),
        tags$li(tags$a(href = "#conclusion", tags$strong("Conclusion")))
        )
  ),
  
  br(),
  br(),
  
  #### motivation ####
  
  tags$header(
    id = "motivation", 
    class = "colourheader",
    tags$div(
      class = "paddeddiv",
      style = "position: relative;",
      tags$h2(paste0("Motivation"), style = "font-weight: bold; text-align: center;"),
      p(style = "margin-top: 5px; white-space: normal;", HTML(motivation_one)),
      p(style = "margin-top: 5px;", paste0(motivation_two)),
      p(style = "margin-top: 5px;", paste0(motivation_three)),
      p(style = "margin-top: 20px;", paste0(date))
    )
  ),
  
  br(),
  br(),
  
  div(
    class = "bigfixedimage",
    style =  paste0("background-image: url('psg.jpg');min-height: 100vh;")
  ),
  
  br(),
  br(),
  
  #### Exploratory analysis ####
  tags$header(id = "exploratory_analysis", class="colourheader",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Exploratory analysis"), style = "font-weight: bold; text-align: center;"),
                       p(style = "margin-top: 5px;", paste0(exploratory_analysis_one))
              )
  ),
  
  br(),
  br(),
 
  #### European performance over time ####
  
  tags$div(ID = "time_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "European performance over time, from 1999-2000 to 2025-26"),
                           plotlyOutput("european_performance_over_time_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="time_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Spanish teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_one)),
                 
                 div(class="time_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" English teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_two)),
                 
                 div(class="time_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" German teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_three)),
                 
                 div(class="time_plot text-article", `data-width`="1",`data-index`="3",
                     p(strong(" Italian teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_four)),
                 
                 div(class="time_plot text-article", `data-width`="1",`data-index`="4",
                     p(strong(" French teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_five)),
                 
                 div(class="time_plot text-article", `data-width`="1",`data-index`="5",
                     p(strong(" Portuguese teams European performance "),
                       br(),
                       europe_s_top_6_leagues_european_performance_since_1999_2000_six))
               ))
  ),
  
  br(),
  br(),
  
  #### Variable selection ####
  tags$header(id = "variable_selection", class="colourheader3",
              tags$div(
                class = "paddeddiv",
                style = "position: relative;",
                tags$h3(
                  "Variables used in analysis of leagues competitiveness",
                  style = "font-weight: bold; text-align: center;"
                ),
                lapply(
                  c(
                    variables_used_in_analysis_of_leagues_competitiveness_one,
                    variables_used_in_analysis_of_leagues_competitiveness_two,
                    variables_used_in_analysis_of_leagues_competitiveness_three,
                    variables_used_in_analysis_of_leagues_competitiveness_four,
                    variables_used_in_analysis_of_leagues_competitiveness_five,
                    variables_used_in_analysis_of_leagues_competitiveness_six,
                    variables_used_in_analysis_of_leagues_competitiveness_seven,
                    variables_used_in_analysis_of_leagues_competitiveness_eight,
                    variables_used_in_analysis_of_leagues_competitiveness_nine,
                    variables_used_in_analysis_of_leagues_competitiveness_ten,
                    variables_used_in_analysis_of_leagues_competitiveness_eleven,
                    variables_used_in_analysis_of_leagues_competitiveness_twelve,
                    variables_used_in_analysis_of_leagues_competitiveness_thirteen,
                    variables_used_in_analysis_of_leagues_competitiveness_fourteen,
                    variables_used_in_analysis_of_leagues_competitiveness_fifteen,
                    variables_used_in_analysis_of_leagues_competitiveness_sixteen
                  ),
                  function(x) p(style = "margin-top: 5px;", HTML(x))
                )
              )
  ),
  
  br(),
  br(),
  
  #### League average characteristics ####
  
  tags$div(ID = "league_averages_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Average characteristics of leagues, from 1999-2000 to 2025-26"),
                           plotlyOutput("league_characteristics_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Spanish teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_one)),
                 
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" English teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_two)),
                 
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" German teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_three)),
                 
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="3",
                     p(strong(" Italian teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_four)),
                 
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="4",
                     p(strong(" French teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_five)),
                 
                 div(class="league_averages_plot text-article", `data-width`="1",`data-index`="5",
                     p(strong(" Portuguese teams European performance "),
                       br(),
                       characteristics_of_leagues_since_1999_2000_six))
               ))
  ),
  
  br(),
  br(),
  
  tags$header(class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       p(style="margin-top: 5px;",paste0(characteristics_of_leagues_extra_one)),
                       p(style="margin-top: 5px;",paste0(characteristics_of_leagues_extra_two))
              )
  ),
  
  br(),
  br(),
  
  #### Basic profiles characteristics ####
  tags$header(id = "basic_profiling", class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       p(style="margin-top: 5px;",paste0(characteristics_of_leagues_grouped_by_performance))
              )
  ),
  
  br(),
  br(),
  
  tags$div(ID = "basic_profiling_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Average characteristics of leagues, grouped by performance"),
                           plotlyOutput("basic_profiles_characteristic_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="basic_profiling_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Characteristics of worst performing European seasons "),
                       br(),
                       characteristics_of_leagues_grouped_by_performance_one)),
                 
                 div(class="basic_profiling_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" Characteristics of best performing European seasons "),
                       br(),
                       characteristics_of_leagues_grouped_by_performance_two)),
                 
                 div(class="basic_profiling_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" Characteristics of middle performing European seasons "),
                       br(),
                       characteristics_of_leagues_grouped_by_performance_three))
               ))
  ),
  
  br(),
  br(),
  
  div(
    class = "bigfixedimage",
    style =  paste0("background-image: url('aston-villa.jpg');min-height: 100vh;")
  ),
  
  br(),
  br(),
  
  #### Modelling ####
  tags$header(id = "modelling", class="colourheader",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Modelling"), style = "font-weight: bold; text-align: center;"),
                       p(style="margin-top: 5px;",paste0(modelling_one)),
                       p(style="margin-top: 5px;",paste0(modelling_two))
              )
  ),
  
  br(),
  br(),
  
  #### Variable creation ####
  tags$header(id = "variable_creation", class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Variable creation"), style = "font-weight: bold; text-align: center;"),
                       tags$h3(paste0(competitiveness_indices), style = "font-weight: bold;"),
                       lapply(
                         c(
                           competitiveness_indices_one,
                           competitiveness_indices_two,
                           competitiveness_indices_three,
                           competitiveness_indices_four,
                           competitiveness_indices_five,
                           competitiveness_indices_six,
                           competitiveness_indices_seven
                         ),
                         function(x) p(style = "margin-top: 5px;", HTML(x))
                       ),
                       br(),
                       tags$h3(paste0(principal_component_analysis_pca), style = "font-weight: bold;"),
                       lapply(
                         c(
                           principal_component_analysis_pca_one,
                           the_five_principal_components_can_be_broadly_interpreted_as,
                           the_five_principal_components_can_be_broadly_interpreted_as_one,
                           the_five_principal_components_can_be_broadly_interpreted_as_two,
                           the_five_principal_components_can_be_broadly_interpreted_as_three,
                           the_five_principal_components_can_be_broadly_interpreted_as_four,
                           the_five_principal_components_can_be_broadly_interpreted_as_five,
                           the_five_principal_components_can_be_broadly_interpreted_as_six
                         ),
                         function(x) p(style = "margin-top: 5px;", HTML(x))
                       )
              )
  ),
  
  br(),
  br(),
  
  #### Regression ####
  tags$header(id = "regression", class="colourheader2",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Regression analysis"), style = "font-weight: bold; text-align: center;"),
                       p(style="margin-top: 5px;",paste0(regression_analysis_one)),
                       p(style="margin-top: 5px;",paste0(regression_analysis_two)),
                       tags$button(
                         class = "btn btn-light mt-3 detail-toggle-btn-black",
                         type = "button",
                         "data-toggle-target" = "#regression-moreContent",
                         "data-show-text" = "Click to view more detailed description of methodology ▼",
                         "data-hide-text" = "Show less ▲",
                         "Click to view more detailed description of methodology ▼"
                       ),
                       tags$div(
                         id = "regression-moreContent",
                         class = "collapse mt-3",
                         p(style = "margin-top: 5px;", paste0(hidden_click_to_view_more_detailed_description_of_methodology_one)),
                         p(style = "margin-top: 5px;", paste0(hidden_click_to_view_more_detailed_description_of_methodology_two)),
                         p(style = "margin-top: 5px;", paste0(hidden_click_to_view_more_detailed_description_of_methodology_three))
                       ),
              )
  ),
  
  br(),
  br(),
  
  #### Regression in one season ####
  tags$header(id = "regression_current_year", class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Regression analysis on league characteristics and same season's European performance"), style = "font-weight: bold; text-align: center;"),
                       p(style = "margin-top: 5px;", paste0(on_league_characteristics_and_same_season_s_european_performance_one))
              )
  ),
  
  br(),
  br(),
  
  tags$div(ID = "regression_current_year_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Coefficient estimates for regression"),
                           plotlyOutput("regression_coefficients_current_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="regression_current_year_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Using all variables (R2 = 0.069) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_two)),
                 
                 div(class="regression_current_year_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" Using principle components (R2 = 0.049) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_three)),
                 
                 div(class="regression_current_year_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" Using competitive indices (R2 = 0.040) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_four))
               ))
  ),
  
  br(),
  br(),
  
  #### Regression in next season ####
  tags$header(id = "regression_next_year", class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Regression analysis on league characteristics and next season's European performance"), style = "font-weight: bold; text-align: center;"),
                       p(style = "margin-top: 5px;", paste0(on_league_characteristics_and_next_season_s_european_performance_one))
              )
  ),
  
  br(),
  br(),
  
  tags$div(ID = "regression_next_year_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Coefficient estimates for regression"),
                           plotlyOutput("regression_coefficients_next_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="regression_next_year_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Using all variables (R2 = 0.128) "),
                       br(),
                       on_league_characteristics_and_next_season_s_european_performance_two)),
                 
                 div(class="regression_next_year_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" Using principle components (R2 = 0.112) "),
                       br(),
                       on_league_characteristics_and_next_season_s_european_performance_three)),
                 
                 div(class="regression_next_year_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" Using competitive indices (R2 = 0.090) "),
                       br(),
                       on_league_characteristics_and_next_season_s_european_performance_four))
               ))
  ),
  
  br(),
  br(),
  
  #### Regression by competition ####
  tags$header(id = "regression_competition", class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Regression analysis on league characteristics and same season's European performance by competition"), style = "font-weight: bold; text-align: center;"),
                       p(style = "margin-top: 5px;", paste0(on_league_characteristics_and_same_season_s_european_performance_by_co_one))
              )
  ),
  
  br(),
  br(),
  
  tags$div(ID = "regression_competition_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Coefficient estimates for regression"),
                           plotlyOutput("regression_coefficients_competition_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="regression_competition_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Using all variables (R2 = 0.099) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_by_co_two)),
                 
                 div(class="regression_competition_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" Using principle components (R2 = 0.049) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_by_co_three)),
                 
                 div(class="regression_competition_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" Using competitive indices (R2 = 0.042) "),
                       br(),
                       on_league_characteristics_and_same_season_s_european_performance_by_co_four))
               ))
  ),
  
  br(),
  br(),
  
  #### Clustering ####
  tags$header(id = "clustering", class="colourheader2",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Clustering to group similar seasons together"), style = "font-weight: bold; text-align: center;"),
                       p(style = "margin-top: 5px;", paste0(clustering_to_group_similar_seasons_together_one)),
                       p(style = "margin-top: 5px;", paste0(clustering_to_group_similar_seasons_together_two)),
                       p(style = "margin-top: 5px;", paste0(clustering_to_group_similar_seasons_together_three))
              )
  ),
  
  br(),
  br(),
  
  tags$div(ID = "clustering_plot",
           div(class="scrolly",
               tags$figure(class="sticky",style=("order: 0; display: flex; flex-direction: column;"),
                           tags$h4(style="text-align: center;", "Average characteristics of clusters"),
                           plotlyOutput("clustering_characteristics_plot", height = "100%")
               ),
               
               tags$article(
                 div(class="clustering_plot text-article", `data-width`="1",`data-index`="0",
                     p(strong(" Elite competition with wider league separation "),
                       br(),
                       radar_plots_for_clusters_one)),
                 
                 div(class="clustering_plot text-article", `data-width`="1",`data-index`="1",
                     p(strong(" Elite dominance across the league "),
                       br(),
                       radar_plots_for_clusters_two)),
                 
                 div(class="clustering_plot text-article", `data-width`="1",`data-index`="2",
                     p(strong(" Most competitive league profile "),
                       br(),
                       radar_plots_for_clusters_three))
               ))
  ),
  
  br(),
  br(),
  
  tags$header(class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       p(style = "margin-top: 5px;", paste0(radar_plots_for_clusters_overall))
              )
  ),
  
  br(),
  br(),
  
  div(
    class = "bigfixedimage",
    style =  paste0("background-image: url('cpfc.jpg');min-height: 100vh;")
  ),
  
  #### Conclusion ####
  tags$header(id = "conclusion", class="colourheader",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Conclusion"), style = "font-weight: bold; text-align: center;"),
                       lapply(
                         c(
                           overall_conclusion_one,
                           overall_conclusion_two,
                           overall_conclusion_three,
                           overall_conclusion_four,
                           overall_conclusion_five,
                           overall_conclusion_six,
                           overall_conclusion_seven
                         ),
                         function(x) {
                           p(
                             style = "margin-top: 5px;",
                             HTML(x)
                           )
                         }
                       )
              )
  ),
  
  br(),
  br(),
  
  #### Limitations ####
  tags$header(class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Limitations"), style = "font-weight: bold; text-align: center;"),
                       lapply(
                         c(
                           limitations_one,
                           limitations_two,
                           limitations_three,
                           limitations_four,
                           limitations_five,
                           limitations_six,
                           limitations_seven
                         ),
                         function(x) {
                           p(
                             style = "margin-top: 5px;",
                             HTML(x)
                           )
                         }
                       )
              )
  ),
  
  br(),
  br(),
  
  #### Footnote ####
  tags$header(class="colourheader3",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h2(paste0("Data collection, sources and analysis process"), style = "font-weight: bold; text-align: center;"),
                       lapply(
                         c(
                           data_sources_and_how_data_was_collected_and_analysis_was_done_one,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_eleven,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_two,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_three,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_four,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_five,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_six,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_seven,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_eight,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_nine,
                           data_sources_and_how_data_was_collected_and_analysis_was_done_ten
                         ),
                         function(x) {
                           p(
                             style = "margin-top: 5px;",
                             HTML(x)
                           )
                         }
                       )
              )
  ),
  
  br(),
  br(),
  
  #### ending section ####
  
  tags$header(class="colourheader",
              style="background:#010056 ; color:white;",
              tags$div(class="paddeddiv",style="position: relative;",
                       tags$h1(paste0(title)),
                       tags$h3(name),
                       tags$h3(date))
              ),
  
  
  #### expandable/collapsable text function ####
  
  tags$script(HTML("
    document.addEventListener('DOMContentLoaded', function() {
      document.querySelectorAll('[data-toggle-target]').forEach(function(button) {
        const targetSelector = button.getAttribute('data-toggle-target');
        const target = document.querySelector(targetSelector);
        if (!target) return;
  
        const showText = (button.getAttribute('data-show-text') || button.textContent || '').trim();
        const hideText = (button.getAttribute('data-hide-text') || 'Show less ▲').trim();
  
        const isVisible = function(el) {
          return window.getComputedStyle(el).display !== 'none' && !el.hidden;
        };
        button.textContent = isVisible(target) ? hideText : showText;
  
        button.addEventListener('click', function() {
          if (isVisible(target)) {
            target.classList.remove('show');
            target.style.display = 'none';
            button.textContent = showText;
          } else {
            target.classList.add('show');
            target.style.display = 'block';
            button.textContent = hideText;
          }
        });
      });
    });
  ")),
  
  #### scrolly javascript ####
  
  HTML("<script src='https://unpkg.com/d3@5.4.0/dist/d3.min.js'></script>"),
  HTML("<script src='https://unpkg.com/enter-view@1.0.0/enter-view.min.js'></script>"),
  HTML("<script src='https://unpkg.com/stickyfilljs@2.0.5/dist/stickyfill.js'></script>"),
  
  HTML(as.character(create_scrolly_side("time_plot")[2])),
  HTML(as.character(create_scrolly_side("league_averages_plot")[2])),
  HTML(as.character(create_scrolly_side("basic_profiling_plot")[2])),
  HTML(as.character(create_scrolly_side("regression_current_year_plot")[2])),
  HTML(as.character(create_scrolly_side("regression_next_year_plot")[2])),
  HTML(as.character(create_scrolly_side("regression_competition_plot")[2])),
  HTML(as.character(create_scrolly_side("clustering_plot")[2]))
)