Clean Up Select Form in Shiny Application with ShinyWidgets and bslib

Question

The following code can be used to reproduce my issue and help illustrate my question. When using the litera theme, box 2 in the UI renders somewhat "ugly" on screen. You can see in this that box 2 has a little bit of white edge on the corner.

I prefer the functionality of box 2 from ShinyWidgets (especially for multiple select), but only if I can get it to look a bit more professional. This seems to be theme-specific. If I change theme to "flatly" both forms look nice.

Also, the browse button with this theme doesn't seem to quite be lined up with its input box.

My two questions then are: 1) Does anyone know how to remove that little bit of color inside box 2 so it is white and renders more like box1? Second, any suggestions on how to clean up the browse so it lines up a bit more and looks cleaner?

library(shiny)
library(bslib)
library(shinyWidgets)

ui <- fluidPage(
    navbarPage(
        theme = bs_theme(bootswatch = "litera"),
        title = 'Methods',
        tabPanel('One'),
    ),  
    sidebarLayout(
        sidebarPanel(
            fileInput('input0', 'Browse'),
            uiOutput("input1"),
            uiOutput("input2")
        ),
        mainPanel(
            h1('Hello World!'),
        ),
    )
)

server <- function(input, output) {
output$input1 <- renderUI({
    selectInput("input1", "Choose:", letters[1:5])
})

output$input2 <- renderUI({
    pickerInput("input2", "Choose:", letters[1:5])
})

}

shinyApp(ui, server)