title: Remove the dark space at the top of the right sidebar in a shinydashboardPlus
body: <p>I have a shinydashboard with a rightsidebar enabled when you press the icon on top right of the app. I would like to remove this darker space above the slider. Is that possible? </p>
  
  <p><a href="https://i.stack.imgur.com/ynflG.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ynflG.png" alt="enter image description here"></a></p>
  
  <pre><code>library(shiny)
  library(shinydashboard)
  shinyApp(
    ui = dashboardPagePlus(
      header = dashboardHeaderPlus(
        enable_rightsidebar = TRUE,
        rightSidebarIcon = "gears"
      ),
      sidebar = dashboardSidebar(),
      body = dashboardBody(),
      rightsidebar = rightSidebar(
        background = "dark",
  
          sliderInput(
            "obs",
            "Number of observations:",
            min = 0, max = 1000, value = 500
          )
  
  
      ),
      title = "Right Sidebar"
    ),
    server = function(input, output) { }
  )
  </code></pre>