styles.css

.bslib-sidebar-layout>.sidebar>.sidebar-content {
  padding: 1.5rem;
}

.bslib-sidebar-layout>.main {
  padding: 1.5rem;
}

.shiny-notification-panel {
  position: fixed;
  top: calc(0%);
  left: calc(50% - 100px);
  padding: 10px 10px;
  width: 200px;
  background-color: rgba(182, 186, 191, 1);
}