.page {
  background-image: url("../images/background.png");
  background-color: #fff;
  color: #222;
  font-family: "IBM Plex Sans JP", sans-serif;
}

.page code, .page pre {
  font-family: "IBM Plex Mono", monospace;
}

.page::before {
  content: '';
  position: absolute;
  bottom: 40px;
  left: 0;
  width: 100%;
  height: 120px;
  background-image:
    url("../images/hero.png"),
    url("../images/mage.png"),
    url("../images/priest.png"),
    url("../images/warrior.png");
  background-repeat: no-repeat;
  background-size: auto 100%;
  background-position: 55% bottom, 68% bottom, 81% bottom, 94% bottom;
  image-rendering: pixelated;
  z-index: 105;
}

.page::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 40px;
  background-image: url("../images/h3_pattern.svg");
  background-repeat: repeat-x;
  background-size: auto 100%;
  background-position: bottom left;
}

.page:not(:has(.page-header)) .page-content {
  top: 45%;
}

#cover {
  background-image: url("../images/cover_background.png");
  background-size: auto 100%;
  background-position: center;
  background-repeat: no-repeat;
  color: #fff;
}

#cover::before,
#cover::after {
  content: none;
}

#cover .page-header {
  top: 12%;
}

.slide .page-header {
  margin-top: 0.5em;
  width: 80%;
  left: 0;
  right: 0;
  margin-left: auto;
  margin-right: auto;
}

h2 {
  font-family: "IBM Plex Sans JP", sans-serif;
  color: #000;
  padding: 13px 13px 13px 100px;
  box-sizing: border-box;
  text-align: left;
  position: relative;
  background:
    url("../images/h2_line_top.svg") left top / 100% 18px no-repeat,
    url("../images/h2_line_bottom.svg") left bottom / 100% 18px no-repeat,
    linear-gradient(#000, #000) left top 18px / 6px calc(100% - 36px) no-repeat,
    linear-gradient(#000, #000) right top 18px / 6px calc(100% - 36px) no-repeat,
    #fff;
}

h2 code {
  font-size: 1em;
}

h2::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 8px;
  width: 80px;
  height: 80px;
  background-image: url("../images/ruby.png");
  background-size: contain;
  background-repeat: no-repeat;
  transform: translateY(-50%);
  image-rendering: pixelated;
}

#cover .page-content {
  position: relative;
  margin-top: 3em;
}

#cover .author {
  position: relative;
  float: right;
  margin-top: 3em;
  right: 3em;
}

#cover .icon {
  position: relative;
  top: 10px;
  left: 30em; 
}

#cover .icon img {
  width: 128px;
}

.books img {
  margin: auto;
  display: block;
  width: 80%;
}

.QR img {
  margin: auto;
  display: block;
  width: 35%;
}

.whats_ruby_wasm img {
  margin: auto;
  display: block;
}

.whats_druby img {
  margin: auto;
  display: block;
  width: 80%;
}

.No_need_JSON_API img {
  margin: auto;
  display: block;
  width: 80%;
}

.Share_objects img {
  margin: auto;
  display: block;
  width: 80%;
}

.gibier2 img {
  margin: auto;
  display: block;
  width: 75%;
}

.center {
  text-align: center;
  font-size: 120%;
  margin-top: 2em;
}

a:link {
  color: #48e;
  text-decoration: none;
}

a:visited {
  color: #48e;
  text-decoration: none;
}

a:hover {
  color: #48a;
  text-decoration: underline;
}

a:active {
  color: #48e;
  text-decoration: none;
}

.page td, .page th {
  padding: 10px 30px;
}

.page th {
  color: #fff;
  background: #333;
}

.page table tr:nth-child(odd) {
  background: #eee;
}

.page table tr:nth-child(even) {
  background: #fff;
}

.page pre.highlight {
  font-size: 0.6em;
  padding: 0.5em;
  border-radius: 0 0.3em 0.3em 0.3em;
}

.page p:has(.file-ref) {
  display: inline-block;
  background-color: #282c34;
  color: #abb2bf;
  font-size: 0.5em;
  padding: 0.3em 0.8em;
  margin-bottom: 0;
  border-radius: 0.3em 0.3em 0 0;
}

.page p:has(.file-ref) .file-ref {
  color: #e6c07b;
}

.page p:has(.file-ref) + pre.highlight {
  margin-top: 0;
}

.page ul {
  list-style: none;
  padding-left: 1.5em;
}

.page ul li {
  position: relative;
  padding-left: 0.5em;
}

.page ul li::before {
  content: '';
  position: absolute;
  left: -1.2em;
  top: 0.15em;
  width: 0.9em;
  height: 0.9em;
  background-image: url("../images/key.png");
  background-size: contain;
  background-repeat: no-repeat;
  image-rendering: pixelated;
}

.page ul ul li::before {
  background-image: url("../images/shield.png");
}