.appStartup {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: grid;
  place-items: center;
  overflow: auto;
  padding: 24px;
  box-sizing: border-box;
  background: #fff;
  color: #252125;
  font: 16px/1.5 Arial, sans-serif;
  text-align: center;
  letter-spacing: 0;
}
.appStartup[hidden], .appStartup button[hidden] { display: none; }
.appStartup > div { max-width: 400px; }
.appStartup img { display: block; margin: 0 auto 16px; }
.appStartup h1 { margin: 0 0 12px; font-size: 24px; line-height: 1.25; }
.appStartup p { margin: 0 0 20px; }
.appStartup button {
  min-height: 44px;
  padding: 10px 24px;
  border: 1px solid #9a2436;
  border-radius: 6px;
  background: #9a2436;
  color: #fff;
  font: 600 16px/1.5 Arial, sans-serif;
  cursor: pointer;
}
.appStartup button:focus-visible { outline: 3px solid #246d82; outline-offset: 3px; }