* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body, html {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: sans-serif;
}

#storybook {
  position: relative;
  width: 100vw;
  height: 100vh;
  background: black;
}

#image-container {
  width: 100%;
  height: 100%;
}

#story-image {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.nav-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 3rem;
  background: rgba(0, 0, 0, 0.4);
  color: white;
  border: none;
  padding: 1rem;
  cursor: pointer;
  z-index: 10;
}

#prev { left: 10px; }
#next { right: 10px; }