PVS-CHAT/components/chat/mode-tab/index.css

.model-tab::before {
  content: '';
  position: absolute;
  left: 0.4rem;
  width: 45%;
  height: 80%;
  background-color: #ffc800;
  border-radius: 2rem;
  transition: all 0.4s;
}
.editor-tab::before {
  left: calc(50%);
}