:root {
  --background-color: #004389;
  --page-background: #ffffff;
}

* {
  box-sizing: border-box;
}

html {
  width: 100%;
  min-height: 100%;
  margin: 0;
  padding: 0;
  background: var(--background-color);

  /*
   * Auf iPhone und Android muss die vergrößerte Seite
   * verschoben werden können.
   */
  overflow: auto;
  -webkit-text-size-adjust: 100%;
}

body {
  width: 100%;
  min-width: 100%;
  min-height: 100%;
  margin: 0;
  padding: 0;

  display: flex;
  align-items: center;
  justify-content: center;

  background: var(--background-color);
  font-family: Arial, Helvetica, sans-serif;

  /*
   * Nicht hidden verwenden.
   * Sonst wird eine per Pinch-Zoom vergrößerte Seite abgeschnitten.
   */
  overflow: auto;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior: contain;
}

#flipbook-wrapper {
  position: relative;

  display: flex;
  align-items: center;
  justify-content: center;

  width: 100%;
  min-height: 100vh;

  padding:
    max(6px, env(safe-area-inset-top))
    max(6px, env(safe-area-inset-right))
    max(6px, env(safe-area-inset-bottom))
    max(6px, env(safe-area-inset-left));
}

#flipbook {
  position: relative;
  flex: 0 0 auto;
  margin: auto;

  /*
   * Browser-Zoom und Verschieben auf Touch-Geräten erlauben.
   */
  touch-action: pan-x pan-y pinch-zoom;
  -webkit-user-select: none;
  user-select: none;
}

#flipbook .page {
  display: flex;
  align-items: center;
  justify-content: center;

  width: 100%;
  height: 100%;

  overflow: hidden;
  background: var(--page-background);
}

#flipbook canvas {
  display: block;
  max-width: 100%;
  max-height: 100%;
  margin: auto;
  object-fit: contain;
  image-rendering: auto;
}
/* Animierter Ladebildschirm */

.loader-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;

  display: flex;
  align-items: center;
  justify-content: center;

  padding: 20px;
  background: var(--background-color);
}

.loader-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;

  min-width: 190px;
  padding: 28px 34px;

  border-radius: 18px;
  background: rgba(255, 255, 255, 0.96);

  box-shadow:
    0 18px 45px rgba(0, 0, 0, 0.25);
}

.loader-spinner {
  width: 50px;
  height: 50px;

  border: 5px solid #dce8f4;
  border-top-color: #004389;
  border-radius: 50%;

  animation: loader-spin 0.8s linear infinite;
}

.loader-text {
  color: #004389;
  font-size: 17px;
  font-weight: 700;
  text-align: center;
}

@keyframes loader-spin {
  to {
    transform: rotate(360deg);
  }
}

@media (max-width: 768px) {
  #flipbook-wrapper {
    min-height: 100svh;
  }

  .loader-box {
    min-width: 170px;
    padding: 24px 28px;
  }

  .loader-text {
    font-size: 16px;
  }
}