html, body {
  margin: 0;
  height: 100%;
  width: 100%;
  font-family: "EB Garamond", serif;
  background: #2a1a0f url('../bilder/ui/bibliothek.jpg') center/cover no-repeat fixed;
  color: #f4f2e8;
}
header {
  background: rgba(40,20,10,0.95);
  padding: 10px;
  text-align: center;
  border-bottom: 3px solid goldenrod;
}
header button {
  margin: 5px;
  padding: 8px 12px;
  background: goldenrod;
  border: none;
  font-weight: bold;
  cursor: pointer;
}
.library-shelf {
  display: flex;
  justify-content: center;
  gap: 20px;
  padding: 40px;
}
.book-spine {
  width: 70px;
  height: 320px;
  background: #552200;
  border: 2px solid goldenrod;
  display: flex;
  align-items: center;
  justify-content: center;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-weight: bold;
  font-size: 16px;
  color: gold;
  font-family: "Cinzel Decorative", serif;
  box-shadow: 2px 2px 8px rgba(0,0,0,0.6);
  transition: transform 0.3s, background 0.3s;
}
.book-spine:hover { transform: scale(1.1); background: #773300; }
.spine-title { transform: rotate(180deg); }
#flipbook {
  width: 100%;
  height: calc(100% - 150px);
  margin: auto;
}
#flipbook .page {
  background: url('../bilder/ui/pergament.jpg') center/cover no-repeat;
  border: 2px solid #ccc;
  padding: 40px;
  box-sizing: border-box;
  font-size: 20px;
  line-height: 1.6;
}
header .controls button {
  margin: 0 5px;
  padding: 6px 12px;
  background: goldenrod;
  border: none;
  font-weight: bold;
  cursor: pointer;
}