使导航栏标签在R中垂直居中

<nav>
  <ul>
    <li><a href="#">标签1</a></li>
    <li><a href="#">标签2</a></li>
    <li><a href="#">标签3</a></li>
  </ul>
</nav>

nav ul {
  display: flex;
  list-style-type: none;
  padding: 0;
  margin: 0;
}

nav li {
  margin-right: 10px;
}

nav li a {
  text-decoration: none;
  color: black;
  padding: 5px;
  border: 1px solid black;
  display: flex;
  align-items: center;
}

library(shiny)

ui <- fluidPage(
  tags$head(
    tags$style(HTML("
      nav ul {
        display: flex;
        list-style-type: none;
        padding: 0;
        margin: 0;
      }

      nav li {
        margin-right: 10px;
      }

      nav li a {
        text-decoration: none;
        color: black;
        padding: 5px;
        border: 1px solid black;
        display: flex;
        align-items: center;
      }
    "))
  ),
  nav(
    ul(
      li(a("标签1", href = "#")),
      li(a("标签2", href = "#")),
      li(a("标签3", href = "#"))
    )
  )
)

server <- function(input, output) {
  
}

shinyApp(ui, server)