.sidebar {
  background: #333;
  bottom: 0;
  max-width: 250px;
  overflow: auto;
  padding: 2em 1em;
  pointer-events: none;
  position: fixed;
  right: 0;
  top: 0;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0, 0, 0.3, 1);
  width: 100%;
  will-change: transform;
  z-index: 100000;
}

.sidebar--open {
  pointer-events: auto;
  transform: none;
  will-change: initial;
}

.sidebar__toggle {
  background: url('../assets/img/close.svg') no-repeat center center / 0.75rem 0.75rem;
  border: 0;
  cursor: pointer;
  font-size: 0;
  height: 2rem;
  opacity: 0.5;
  position: fixed;
  right: 0;
  top: 0;
  transition: opacity 0.3s;
  width: 2rem;

  &:hover {
    opacity: 1;
  }
}

.sidebar {
  background: #333;
  bottom: 0;
  max-width: 250px;
  overflow: auto;
  padding: 2em 1em;
  pointer-events: none;
  position: fixed;
  right: 0;
  top: 0;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0, 0, 0.3, 1);
  width: 100%;
  will-change: transform;
  z-index: 100000;
}

.sidebar--open {
  pointer-events: auto;
  transform: none;
  will-change: initial;
}

.sidebar__toggle {
  background: url('../assets/img/close.svg') no-repeat center center / 0.75rem 0.75rem;
  border: 0;
  cursor: pointer;
  font-size: 0;
  height: 2rem;
  opacity: 0.5;
  position: fixed;
  right: 0;
  top: 0;
  transition: opacity 0.3s;
  width: 2rem;
  z-index: 100;

  &:hover {
    opacity: 1;
  }
}

Fix close button showing underneath colour tiles
Fix close button showing underneath colour tiles
