.periodic-workbench,
.periodic-bottom-grid {
  display: grid;
  grid-template-columns: minmax(320px, .95fr) minmax(0, 1.05fr);
  gap: 16px;
  align-items: stretch;
}
.periodic-bottom-grid,
.periodic-table-panel {
  margin-top: 16px;
}
.periodic-panel {
  min-width: 0;
  background: #fff;
}
.periodic-panel-header {
  gap: 12px;
}
.periodic-panel-header > span:first-child {
  flex: 1;
  min-width: 0;
}
.periodic-panel-header i {
  margin-right: 6px;
}
.periodic-status {
  flex: 0 1 auto;
  min-width: 0;
  color: var(--text-3);
  font-size: 12.5px;
  font-weight: 500;
  text-align: right;
}
.periodic-panel-body {
  gap: 14px;
  background: #fff;
}
.periodic-field {
  display: grid;
  gap: 6px;
  min-width: 0;
  margin: 0;
  color: var(--text-2);
  font-size: 13.5px;
  font-weight: 600;
}
.periodic-field .form-control {
  min-width: 0;
  width: 100%;
}
.periodic-filter-row,
.periodic-state-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.periodic-filter-row .btn,
.periodic-state-row .btn,
.periodic-formula-row .btn {
  justify-content: center;
}
.periodic-filter-row .btn i,
.periodic-state-row .btn i,
.periodic-formula-row .btn i,
.periodic-panel-header .btn i {
  margin-right: 6px;
}
.periodic-stats,
.periodic-detail-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}
.periodic-stats > div,
.periodic-detail-grid > div,
.periodic-guide-grid > div {
  display: grid;
  gap: 4px;
  min-width: 0;
  padding: 11px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-soft);
}
.periodic-stats span,
.periodic-detail-grid span,
.periodic-use-box span,
.periodic-guide-grid span,
.periodic-element small,
.periodic-legend span {
  color: var(--text-3);
  font-size: 12.5px;
  line-height: 1.35;
}
.periodic-stats strong {
  overflow: hidden;
  color: var(--text);
  font-size: 18px;
  line-height: 1.25;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.periodic-detail {
  display: grid;
  grid-template-columns: 86px minmax(0, 1fr);
  gap: 14px;
  align-items: center;
}
.periodic-detail-symbol {
  display: grid;
  place-items: center;
  min-height: 86px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--primary-soft);
  color: var(--primary);
  font-size: 34px;
  font-weight: 800;
  line-height: 1;
}
.periodic-detail h3 {
  margin: 0 0 6px;
  color: var(--text);
  font-size: 20px;
  line-height: 1.25;
}
.periodic-detail p {
  margin: 0;
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.5;
}
.periodic-detail-grid strong {
  color: var(--text);
  font-size: 14px;
  line-height: 1.35;
  overflow-wrap: anywhere;
}
.periodic-use-box,
.periodic-formula-result,
.periodic-config-box {
  display: grid;
  gap: 5px;
  min-width: 0;
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
}
.periodic-config-box > span {
  display: flex;
  align-items: baseline;
  gap: 6px;
  color: var(--text-3);
  font-size: 12.5px;
  line-height: 1.35;
}
.periodic-config-box small {
  color: var(--text-3);
  font-size: 11.5px;
  font-weight: 400;
}
.periodic-config-box code {
  background: transparent;
  border: none;
  padding: 0;
  color: var(--text);
  font-size: 14.5px;
  line-height: 1.5;
  overflow-wrap: anywhere;
}
.periodic-use-box strong,
.periodic-guide-grid strong {
  color: var(--text);
  font-size: 13.5px;
  line-height: 1.35;
}
.periodic-detail-footer {
  display: flex;
  justify-content: flex-end;
}
.periodic-detail-footer a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
}
.periodic-detail-footer a:hover {
  text-decoration: underline;
}
.periodic-message {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-soft);
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.45;
}
.periodic-table-scroll {
  overflow-x: auto;
  padding-bottom: 4px;
}
.periodic-grid {
  display: grid;
  grid-template-columns: repeat(18, minmax(68px, 1fr));
  grid-auto-rows: minmax(78px, auto);
  gap: 6px;
  min-width: 1280px;
}
.periodic-element {
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-width: 0;
  padding: 7px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  color: var(--text);
  text-align: left;
  cursor: pointer;
}
.periodic-element:hover,
.periodic-element:focus,
.periodic-element.is-active {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}
.periodic-element.is-dim {
  opacity: .24;
}
.periodic-number {
  color: var(--text-3);
  font-size: 11px;
  line-height: 1.1;
}
.periodic-symbol {
  align-self: center;
  color: var(--text);
  font-size: 22px;
  font-weight: 800;
  line-height: 1;
}
.periodic-name {
  display: block;
  overflow: hidden;
  color: var(--text-2);
  font-size: 11.5px;
  line-height: 1.2;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.periodic-mass {
  color: var(--text-3);
  font-size: 11px;
  line-height: 1.2;
}
.periodic-category-alkali-metal { background: #fee2e2; }
.periodic-category-alkaline-earth-metal { background: #ffedd5; }
.periodic-category-transition-metal { background: #dbeafe; }
.periodic-category-post-transition-metal { background: #e0f2fe; }
.periodic-category-metalloid { background: #dcfce7; }
.periodic-category-nonmetal { background: #fef9c3; }
.periodic-category-halogen { background: #ede9fe; }
.periodic-category-noble-gas { background: #fce7f3; }
.periodic-category-lanthanide { background: #ccfbf1; }
.periodic-category-actinide { background: #fae8ff; }
.periodic-category-unknown { background: #f1f5f9; }
.periodic-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
}
.periodic-legend span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.periodic-legend i {
  width: 14px;
  height: 14px;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--legend-color);
}
.periodic-formula-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
  align-items: end;
}
.periodic-formula-result {
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.5;
}
.periodic-formula-result strong {
  color: var(--primary);
  font-size: 18px;
}
.periodic-guide-grid {
  display: grid;
  gap: 10px;
}
:root[data-theme="dark"] .periodic-panel,
:root[data-theme="dark"] .periodic-panel-body,
:root[data-theme="dark"] .periodic-use-box,
:root[data-theme="dark"] .periodic-formula-result,
:root[data-theme="dark"] .periodic-config-box {
  background: #161b22;
}
:root[data-theme="dark"] .periodic-element,
:root[data-theme="dark"] .periodic-guide-grid > div,
:root[data-theme="dark"] .periodic-stats > div,
:root[data-theme="dark"] .periodic-detail-grid > div {
  background-color: #1f2937;
}
@media (max-width: 991px) {
  .periodic-workbench,
  .periodic-bottom-grid {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 640px) {
  .periodic-panel .form-control-group-body {
    padding: 14px;
  }
  .periodic-panel-header {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    row-gap: 6px;
  }
  .periodic-status {
    text-align: left;
  }
  .periodic-filter-row,
  .periodic-state-row,
  .periodic-stats,
  .periodic-detail-grid,
  .periodic-formula-row {
    display: grid;
    grid-template-columns: 1fr;
  }
  .periodic-filter-row .btn,
  .periodic-state-row .btn,
  .periodic-formula-row .btn {
    width: 100%;
    min-width: 0;
  }
  .periodic-detail {
    grid-template-columns: 68px minmax(0, 1fr);
  }
  .periodic-detail-symbol {
    min-height: 68px;
    font-size: 28px;
  }
}