How can I change the font color of an accordion menu in a shiny app?

I want to recreate the following accordion menu:

I am using the accordion() function from the shinydashboardPlus package, and got to here so far:

I am trying to change the font color to black to match the first image, but adding the following CSS code is not working:

tags$head(
    tags$style(
      HTML("
        .box-title {
          color: black !important;
        }
      ")
    )
  )

If someone could help me to change the font color, and if possible to add the well (AKA: the white rectangle with circled borders around each item of the accordion menu) it would be great!

Here is te full app code:

library(shiny)
library(shinydashboard)
library(shinydashboardPlus)

ui <- fluidPage(
  tags$head(
    tags$style(
      HTML("
        .box-title {
          color: black !important;
        }
      ")
    )
  ),
  accordion(
    id = "covenants",
    accordionItem(
      title = "Cash on cash",
      status = "danger",
      collapsed = TRUE,
      "This is some text!"
    ),
    accordionItem(
      title = "Net Portfolio Yield Percentage",
      status = "warning",
      collapsed = TRUE,
      "This is some text!"
    ),
    accordionItem(
      title = "Minimum Liquidity Amount",
      status = "warning",
      collapsed = TRUE,
      "This is some text!"
    ),
    accordionItem(
      title = "Maximum Debt to Equity Ratio",
      status = "warning",
      collapsed = TRUE,
      "This is some text!"
    ),
    accordionItem(
      title = "Most Favored Nation",
      status = "warning",
      collapsed = TRUE,
      "This is some text!"
    )
  )
)

server <- function(input, output, session) {}

shinyApp(ui, server)

The .box-title selector targets the title of the accordion, which is usually a hyperlink. By default, hyperlinks have a special style that includes a different color for visited and unvisited links. The color property only applies to unvisited links, whereas the :visited selector can be used to target visited links

Therefore, the correct CSS code is:

.box-title a {
  color: black !important;
}