.chem-kb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  width: 100%;
  margin: 0.45rem 0 0.15rem;
  position: sticky;
  bottom: 0;
  z-index: 4;
  padding: 0.45rem;
  background: var(--paper, #fffaf2);
  border-top: 1px solid var(--line, #ddd4c3);
}

.chem-kb-key {
  min-width: 44px;
  min-height: 44px;
  padding: 0.2rem 0.55rem;
  border: 1px solid var(--line, #ddd4c3);
  border-radius: 0.6rem;
  background: var(--card, #fffaf2);
  color: var(--ink, #1c2430);
  font: inherit;
  font-size: 1rem;
  line-height: 1;
  cursor: pointer;
  touch-action: manipulation;
}

.chem-kb-key:hover,
.chem-kb-key:focus-visible {
  border-color: var(--teal, #0f5c56);
}