html,
body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  margin: 0;
  padding: 0;
}
#renderCanvas {
  width: 100%;
  height: 100%;
  touch-action: none;
}
#renderCanvas.dragging {
  cursor: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='32' height='32' viewBox='0 0 32 32'%3E%3Cellipse cx='16' cy='16' rx='14' ry='8' fill='white' stroke='%23333' stroke-width='1.5'/%3E%3Ccircle cx='16' cy='16' r='5' fill='%23333'/%3E%3Ccircle cx='18' cy='14' r='1.5' fill='white' opacity='0.6'/%3E%3C/svg%3E") 16 16, auto;
}

#dropMessage {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: rgba(0, 0, 0, 0.5);
  color: white;
  padding: 20px;
  border-radius: 10px;
  text-align: center;
  font-size: 1.5em;
  pointer-events: auto;
  cursor: pointer;
  user-select: none;
  border: 2px solid transparent;
  transition: transform 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}
#dropMessage:hover {
  transform: translate(-50%, -50%) scale(1.15);
  border-color: rgba(255, 255, 255, 0.8);
  background-color: rgba(0, 0, 0, 0.65);
}

#fileInput {
  display: none;
}

#smallIcon {
  display: block;
  position: absolute;
  bottom: 10px;
  right: 10px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.4) url('../img/upload_icon.png') center / 60%
    no-repeat;
  cursor: pointer;
  border: 2px solid transparent;
  transition: transform 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}
#smallIcon:hover {
  transform: scale(1.15);
  border-color: rgba(255, 255, 255, 0.8);
  background-color: rgba(0, 0, 0, 0.65);
}

#helpIcon {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.4);
  color: #fff;
  font-size: 28px;
  font-weight: bold;
  line-height: 50px;
  text-align: center;
  cursor: pointer;
  user-select: none;
  z-index: 10;
  border: 2px solid transparent;
  transition: transform 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}
#helpIcon:hover {
  transform: scale(1.15);
  border-color: rgba(255, 255, 255, 0.8);
  background-color: rgba(0, 0, 0, 0.65);
}

#helpPopup {
  display: none;
  position: absolute;
  top: 70px;
  right: 10px;
  background: rgba(0, 0, 0, 0.75);
  color: #fff;
  padding: 16px 20px;
  border-radius: 10px;
  font-size: 14px;
  line-height: 1.8;
  z-index: 20;
  max-width: 280px;
  pointer-events: none;
}

#helpPopup::before {
  content: '';
  position: absolute;
  top: -8px;
  right: 20px;
  width: 0;
  height: 0;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  border-bottom: 8px solid rgba(0, 0, 0, 0.75);
}

@media (max-width: 600px) {
  #dropMessage {
    font-size: 1.1em;
    padding: 16px 24px;
    max-width: 85vw;
  }

  #smallIcon,
  #helpIcon {
    width: 56px;
    height: 56px;
  }

  #smallIcon {
    bottom: 12px;
    right: 12px;
  }

  #helpIcon {
    top: 12px;
    right: 12px;
    font-size: 30px;
    line-height: 56px;
  }

  #helpPopup {
    font-size: 16px;
    max-width: 75vw;
    padding: 14px 18px;
  }
}