yckj_framework/d2-admin/src/assets/style/fixed/vue-grid-layout.scss

// vue-splitpane 样式补丁
.vue-grid-item {
  &.vue-grid-placeholder {
    border: 1px solid $color-border-1;
    background-color: rgba(#FFF, .3);
    opacity: 1;
    border-radius: 4px;
  }
}