:root {
  --tsumego-view-background-color: #e2e2e2;
  --diagram-cover-background-color: rgba(250, 250, 250, 0.7);
  --loading-cover-background-gradient: linear-gradient(0deg, #eee, #ddd);
  --loading-bar-background-color: rgba(0, 0, 0, 0.06);
  --loading-bar-background-gradient: linear-gradient(0deg, #3d83b3, #76a3c1);
  --loading-cover-font-color: #000;
}

html[data-theme="light"] {
  --tsumego-view-background-color: #e2e2e2;
  --diagram-cover-background-color: rgba(250, 250, 250, 0.7);
  --loading-cover-background-gradient: linear-gradient(0deg, #eee, #ddd);
  --loading-bar-background-color: rgba(0, 0, 0, 0.06);
  --loading-bar-background-gradient: linear-gradient(0deg, #3d83b3, #76a3c1);
  --loading-cover-font-color: #000;
}

html[data-theme="dark"] {
  --tsumego-view-background-color: #303030;
  --diagram-cover-background-color: rgba(0, 0, 0, 0.7);
  --loading-cover-background-gradient: linear-gradient(0deg, #111, #222);
  --loading-bar-background-color: rgba(250, 250, 250, 0.1);
  --loading-bar-background-gradient: linear-gradient(0deg, #76a3c1, lightblue);
  --loading-cover-font-color: #eee;
}

html {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
}

body {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  background-color: #383838;
  margin: 0;
  padding: 0;
}

#btp-loading-cover {
  position: fixed;
  z-index: 1000;
  visibility: visible;
  opacity: 1;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  background: var(--loading-cover-background-gradient);
  transition: visibility 0.6s, opacity 0.6s linear;
}

#btp-loading-bar {
  position: relative;
  width: 10em;
  height: 2em;
  border-radius: 0.3em;
  background-color: var(--loading-bar-background-color);
  margin-bottom: 1em;
  transition: visibility 0.5s, opacity 0.5s linear;
}

#btp-loading-bar-progress-indicator {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 1%;
  border-radius: 0.3em;
  background: var(--loading-bar-background-gradient);
  box-shadow: 0 0 1vh rgba(0, 0, 0, 0.15);
}

#btp-loading-text {
  position: relative;
  width: 10em;
  height: 1em;
  text-align: center;
  font-family: "Trebuchet MS", geneva, helvetica, arial, tahoma, verdana, sans-serif;
  font-size: 0.8em;
  line-height: 0.8em;
  color: var(--loading-cover-font-color);
}

#btp-tsumego-view {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  background-color: var(--tsumego-view-background-color);
  overflow-x: hidden;
}

#btp-tsumego-view::-webkit-scrollbar {
  width: 3px;
  height: 4px;
  background-color: #555;
}

#btp-tsumego-view::-webkit-scrollbar-thumb {
  background-color: #444;
}

#btp-tsumego-modal-cover {
  visibility: hidden;
  opacity: 0;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 200;
  background-color: rgba(0, 0, 0, 0.6);
  -webkit-transition: visibility 130ms, opacity 130ms ease-in;
  -moz-transition: visibility 130ms, opacity 130ms ease-in;
  transition: visibility 130ms, opacity 130ms ease-in;
}

.modal-cover-animate-in {
  animation: cover-in 200ms linear forwards;
}

.modal-cover-animate-out {
  animation: cover-out 200ms linear forwards;
}

@keyframes cover-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes cover-out {
  from {
    opacity: 1;
  }
  to {
    opacity: 0;
  }
}

#btp-tsumego-diagram-cover {
  visibility: hidden;
  opacity: 0;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 400;
  background-color: var(--diagram-cover-background-color);
  -webkit-transition: visibility 130ms, opacity 130ms ease-in;
  -moz-transition: visibility 130ms, opacity 130ms ease-in;
  transition: visibility 130ms, opacity 130ms ease-in;
  display: flex;
  align-items: center;
  justify-content: center;
}