.lu-topic .gt-nav,
.lu-topic-layout .gt-nav {
  grid-template-columns: repeat(6, minmax(0, 1fr));
}

.lu-chain {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.lu-chain section {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 10px;
  align-items: center;
  min-height: 118px;
  padding: 16px;
  border: 1px solid rgba(148, 163, 184, 0.34);
  border-radius: 14px;
  background: linear-gradient(135deg, #fff, #f8fbff);
}

.lu-chain strong {
  color: #0f172a;
  font-size: 1.2rem;
  text-align: center;
}

.lu-chain span {
  color: #2563eb;
  font-weight: 950;
}

.lu-chain em {
  grid-column: 1 / -1;
  width: fit-content;
  margin: auto;
  padding: 5px 10px;
  border-radius: 999px;
  color: #0f766e;
  background: rgba(20, 184, 166, 0.12);
  font-style: normal;
  font-weight: 900;
}

.lu-lab {
  grid-template-columns: minmax(280px, 360px) minmax(0, 1fr);
}

.lu-select-label,
.lu-case-controls label {
  display: grid;
  gap: 8px;
  color: #334155;
  font-weight: 900;
}

.lu-select-label select,
.lu-case-controls select,
.control-card select {
  min-height: 40px;
  border: 1px solid rgba(148, 163, 184, 0.42);
  border-radius: 12px;
  padding: 0 10px;
  color: #0f172a;
  font-weight: 900;
  background: #fff;
}

.lu-lab-readout {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.lu-lab-readout span {
  display: grid;
  gap: 4px;
  padding: 12px;
  border: 1px solid rgba(148, 163, 184, 0.28);
  border-radius: 12px;
  color: #64748b;
  font-size: 0.78rem;
  font-weight: 900;
  background: #f8fafc;
}

.lu-lab-readout b {
  color: #0f172a;
  font-size: 1rem;
}

.lu-lab-visual,
.lu-exp-visual {
  min-height: 300px;
  padding: 18px;
  border: 1px solid rgba(190, 202, 222, 0.82);
  border-radius: 16px;
  background:
    linear-gradient(rgba(255, 255, 255, 0.86), rgba(255, 255, 255, 0.86)),
    repeating-linear-gradient(0deg, rgba(37, 99, 235, 0.06) 0 1px, transparent 1px 30px),
    repeating-linear-gradient(90deg, rgba(20, 184, 166, 0.05) 0 1px, transparent 1px 30px);
  overflow: hidden;
}

.lu-measure-tape {
  display: grid;
  gap: 18px;
  align-content: center;
  height: 100%;
}

.lu-tape-track {
  position: relative;
  height: 96px;
  border-bottom: 8px solid #f59e0b;
}

.lu-tape-track i {
  position: absolute;
  bottom: -8px;
  width: 2px;
  height: 54px;
  background: #334155;
  transform: translateX(-1px);
}

.lu-tape-track i:nth-child(odd) {
  height: 34px;
}

.lu-tape-track i b {
  position: absolute;
  top: -24px;
  left: -8px;
  color: #475569;
  font-size: 0.75rem;
}

.lu-tape-track span {
  position: absolute;
  left: 0;
  bottom: 10px;
  height: 24px;
  border-radius: 999px;
  background: linear-gradient(90deg, #2563eb, #14b8a6);
}

.lu-tape-labels {
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.lu-tape-labels strong,
.lu-case-scene b,
.lu-case-scene em {
  width: fit-content;
  padding: 6px 10px;
  border-radius: 999px;
  color: #fff;
  background: #2563eb;
  font-style: normal;
  font-weight: 950;
}

.lu-case-scene em,
.lu-tape-labels strong:last-child {
  background: #0f766e;
}

.lu-case-grid {
  grid-template-columns: repeat(3, minmax(260px, 1fr));
}

.lu-case {
  display: grid;
  gap: 12px;
  min-height: 468px;
  padding: 14px;
  border: 1px solid rgba(190, 202, 222, 0.76);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 10px 24px rgba(30, 41, 59, 0.05);
}

.lu-case-head {
  display: grid;
  gap: 4px;
}

.lu-case-head span {
  color: #2563eb;
  font-size: 0.78rem;
  font-weight: 950;
}

.lu-case-head strong {
  color: #0f172a;
  font-size: 1.18rem;
  line-height: 1.2;
}

.lu-case p {
  margin: 0;
  color: #64748b;
  line-height: 1.55;
}

.lu-case-controls {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(112px, 0.34fr);
  gap: 10px;
  align-items: end;
}

.lu-case-controls output {
  color: #0f172a;
  font-weight: 950;
}

.lu-case-controls input {
  width: 100%;
}

.lu-case-scene {
  position: relative;
  display: grid;
  align-content: center;
  gap: 12px;
  min-height: 180px;
  padding: 16px;
  border-radius: 16px;
  background: linear-gradient(145deg, #f8fafc, #eef6ff);
  overflow: hidden;
}

.lu-case-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.lu-case-metrics span {
  display: grid;
  gap: 3px;
  min-width: 0;
  padding: 10px;
  border-radius: 12px;
  color: #64748b;
  background: #f8fafc;
  font-size: 0.74rem;
  font-weight: 900;
}

.lu-case-metrics b {
  color: #0f172a;
  font-size: 0.92rem;
  overflow-wrap: anywhere;
}

.lu-case-result {
  min-height: 58px;
  padding: 12px;
  border-radius: 14px;
  color: #254155;
  background: rgba(236, 253, 245, 0.85);
  font-weight: 850;
  line-height: 1.45;
}

.lu-ruler,
.lu-exp-ruler {
  position: relative;
  height: 44px;
  border-bottom: 7px solid #fbbf24;
}

.lu-ruler i,
.lu-exp-ruler i {
  position: absolute;
  bottom: -7px;
  width: 2px;
  height: 30px;
  background: #475569;
  color: #64748b;
  font-size: 0.68rem;
}

.lu-ruler span {
  position: absolute;
  left: 0;
  bottom: 8px;
  height: 12px;
  border-radius: 999px;
  background: #2563eb;
}

.lu-pencil,
.lu-exp-pencil-body {
  display: flex;
  align-items: center;
  min-height: 28px;
}

.lu-pencil span,
.lu-exp-pencil-body {
  height: 22px;
  border-radius: 999px 8px 8px 999px;
  background: linear-gradient(90deg, #fbbf24 0 80%, #f97316 80% 92%, #334155 92%);
}

.lu-pencil i,
.lu-exp-pencil-body i {
  width: 18px;
  height: 22px;
  border-radius: 8px 0 0 8px;
  background: #fca5a5;
}

.lu-desk-top {
  height: 48px;
  border-radius: 14px;
  background: linear-gradient(180deg, #d97706, #92400e);
  box-shadow: inset 0 -8px rgba(0, 0, 0, 0.12);
}

.lu-desk-legs {
  display: flex;
  justify-content: space-around;
}

.lu-desk-legs i {
  width: 16px;
  height: 56px;
  border-radius: 0 0 8px 8px;
  background: #64748b;
}

.lu-tape-mini,
.lu-height-mark,
.lu-track-note,
.lu-map-pins,
.lu-growth-mark,
.lu-box-arrow,
.lu-phone-mark {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
}

.lu-door-frame {
  position: relative;
  height: 150px;
  width: 120px;
  margin: auto;
  border: 10px solid #92400e;
  border-bottom: 0;
  border-radius: 12px 12px 0 0;
  background: #eff6ff;
}

.lu-door-frame span {
  position: absolute;
  bottom: 0;
  left: 16px;
  right: 16px;
  border-radius: 9px 9px 0 0;
  background: #60a5fa;
}

.lu-door-frame i {
  position: absolute;
  right: 20px;
  top: 58%;
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: #f59e0b;
}

.lu-book-stack {
  position: relative;
  min-height: 95px;
}

.lu-book-stack i {
  position: absolute;
  left: 24%;
  bottom: 8px;
  width: 135px;
  height: 54px;
  border: 2px solid #cbd5e1;
  border-radius: 10px;
  background: #fff;
  box-shadow: 0 8px 14px rgba(15, 23, 42, 0.08);
}

.lu-caliper {
  position: absolute;
  right: 20px;
  bottom: 36px;
  width: 18px;
  border: 4px solid #334155;
  border-left: 0;
  border-radius: 0 8px 8px 0;
}

.lu-wall-room {
  position: relative;
  min-height: 120px;
  border-radius: 14px;
  background:
    linear-gradient(90deg, rgba(148, 163, 184, 0.22) 1px, transparent 1px),
    #fff7ed;
  background-size: 40px 100%;
}

.lu-wall-room i {
  position: absolute;
  top: 22px;
  width: 42px;
  height: 34px;
  border-radius: 8px;
  background: #bfdbfe;
  border: 4px solid #64748b;
}

.lu-wall-room i:nth-child(1) { left: 12%; }
.lu-wall-room i:nth-child(2) { left: 44%; }
.lu-wall-room i:nth-child(3) { left: 76%; }

.lu-wall-room span {
  position: absolute;
  left: 4%;
  bottom: 22px;
  height: 10px;
  border-radius: 999px;
  background: #14b8a6;
}

.lu-track-ring {
  position: relative;
  width: 190px;
  height: 116px;
  margin: auto;
  border: 16px solid #ef4444;
  border-radius: 999px;
  box-shadow: inset 0 0 0 10px #fff, inset 0 0 0 20px #f97316;
}

.lu-track-ring span {
  position: absolute;
  inset: 22px;
  border: 2px dashed rgba(255, 255, 255, 0.9);
  border-radius: 999px;
}

.lu-track-ring i {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 74px;
  height: 4px;
  transform-origin: left center;
  background: #1d4ed8;
}

.lu-track-ring i::after {
  content: "";
  position: absolute;
  right: -6px;
  top: -6px;
  width: 16px;
  height: 16px;
  border-radius: 999px;
  background: #2563eb;
}

.lu-map-route {
  position: relative;
  min-height: 124px;
  border-radius: 14px;
  background:
    linear-gradient(135deg, transparent 45%, rgba(34, 197, 94, 0.18) 46% 55%, transparent 56%),
    linear-gradient(45deg, transparent 45%, rgba(59, 130, 246, 0.18) 46% 55%, transparent 56%),
    #f8fafc;
}

.lu-map-route i {
  position: absolute;
  width: 20px;
  height: 20px;
  border-radius: 999px;
  background: #ef4444;
}

.lu-map-route i:nth-child(1) { left: 12%; top: 64%; }
.lu-map-route i:nth-child(2) { left: 48%; top: 24%; background: #f59e0b; }
.lu-map-route i:nth-child(3) { right: 10%; top: 54%; background: #2563eb; }

.lu-map-route span {
  position: absolute;
  left: 12%;
  top: 58%;
  height: 8px;
  border-radius: 999px;
  background: #14b8a6;
  transform: rotate(-12deg);
  transform-origin: left center;
}

.lu-ribbon-roll {
  width: 74px;
  height: 74px;
  border: 15px solid #ec4899;
  border-radius: 999px;
  background: #fff;
}

.lu-ribbon-strip {
  height: 38px;
  border-radius: 6px;
  background: repeating-linear-gradient(90deg, #ec4899 0 26px, #f9a8d4 26px 40px);
}

.lu-scissors {
  position: absolute;
  right: 24px;
  top: 62px;
  width: 38px;
  height: 38px;
  border-radius: 999px;
  border: 5px solid #64748b;
}

.lu-scissors::after {
  content: "";
  position: absolute;
  left: -28px;
  top: 16px;
  width: 48px;
  height: 4px;
  background: #64748b;
  transform: rotate(-24deg);
}

.lu-tile-grid {
  display: grid;
  grid-template-columns: repeat(3, 42px);
  gap: 5px;
  justify-content: center;
}

.lu-tile-grid i {
  aspect-ratio: 1;
  border-radius: 6px;
  background: linear-gradient(135deg, #14b8a6, #0f766e);
  box-shadow: inset 0 0 0 4px rgba(255, 255, 255, 0.35);
}

.lu-tile-edge {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin: auto;
  border-top: 6px solid #f59e0b;
}

.lu-plant {
  position: relative;
  height: 138px;
  width: 110px;
  margin: auto;
}

.lu-plant i {
  position: absolute;
  left: 22px;
  bottom: 0;
  width: 66px;
  height: 42px;
  border-radius: 12px 12px 22px 22px;
  background: #d97706;
}

.lu-plant span {
  position: absolute;
  left: 52px;
  bottom: 34px;
  width: 8px;
  border-radius: 999px;
  background: #16a34a;
}

.lu-plant em {
  position: absolute;
  left: 56px;
  top: 38px;
  width: 38px;
  height: 22px;
  border-radius: 999px 999px 999px 0;
  background: #22c55e;
  transform: rotate(-20deg);
}

.lu-box {
  position: relative;
  width: 160px;
  height: 104px;
  margin: auto;
  border-radius: 12px;
  background: linear-gradient(135deg, #f59e0b, #b45309);
  box-shadow: inset -34px 0 rgba(255, 255, 255, 0.22);
}

.lu-box i {
  position: absolute;
  inset: 12px 0 auto;
  height: 5px;
  background: rgba(255, 255, 255, 0.5);
}

.lu-box span {
  position: absolute;
  left: 0;
  bottom: -16px;
  height: 6px;
  border-radius: 999px;
  background: #2563eb;
}

.lu-phone {
  position: relative;
  width: 96px;
  height: 146px;
  margin: auto;
  border: 8px solid #111827;
  border-radius: 22px;
  background: linear-gradient(160deg, #bfdbfe, #dbeafe);
}

.lu-phone span {
  position: absolute;
  top: 7px;
  left: 34px;
  width: 22px;
  height: 4px;
  border-radius: 999px;
  background: #111827;
}

.lu-phone i {
  position: absolute;
  left: 44px;
  bottom: 12px;
  width: 6px;
  border-radius: 999px;
  background: #ef4444;
  transform: rotate(-30deg);
  transform-origin: bottom center;
}

.lu-experiment {
  display: grid;
  gap: 18px;
}

.lu-exp-workbench {
  display: grid;
  grid-template-columns: minmax(280px, 360px) minmax(0, 1fr);
  gap: 18px;
  padding-top: 16px;
  border-top: 1px solid rgba(148, 163, 184, 0.24);
}

.lu-exp-story {
  display: grid;
  gap: 12px;
  align-content: start;
  padding: 18px;
  border: 1px solid rgba(20, 184, 166, 0.24);
  border-radius: 16px;
  background: linear-gradient(145deg, #ffffff, #ecfdf5);
  box-shadow: 0 16px 34px rgba(20, 184, 166, 0.08);
}

.lu-exp-story > span {
  width: fit-content;
  padding: 5px 10px;
  border-radius: 999px;
  color: #0f766e;
  background: rgba(20, 184, 166, 0.12);
  font-size: 0.78rem;
  font-weight: 950;
}

.lu-exp-story > strong {
  color: #102033;
  font-size: 1.08rem;
  line-height: 1.35;
}

.lu-exp-story p {
  margin: 0;
  color: #536171;
  line-height: 1.65;
}

.lu-exp-board {
  display: grid;
  gap: 12px;
}

.lu-exp-pencil,
.lu-exp-door,
.lu-exp-map {
  display: grid;
  gap: 16px;
  align-content: center;
  min-height: 260px;
}

.lu-exp-pencil-body {
  position: relative;
}

.lu-exp-pencil-body span {
  position: absolute;
  right: 0;
  top: 0;
  width: 24px;
  height: 22px;
  border-radius: 0 999px 999px 0;
  background: #334155;
}

.lu-exp-equation,
.lu-exp-meter,
.lu-exp-map b,
.lu-exp-map em {
  width: fit-content;
  padding: 8px 12px;
  border-radius: 999px;
  color: #334155;
  background: #e2e8f0;
  font-style: normal;
  font-weight: 950;
}

.lu-exp-equation.is-on,
.lu-exp-meter.is-on,
.lu-exp-map b.is-on,
.lu-exp-map em.is-on {
  color: #fff;
  background: #2563eb;
}

.lu-exp-door-frame {
  position: relative;
  width: 150px;
  height: 190px;
  margin: auto;
  border: 12px solid #92400e;
  border-bottom: 0;
  border-radius: 14px 14px 0 0;
  background: #eff6ff;
}

.lu-exp-door-frame span {
  position: absolute;
  left: 24px;
  right: 24px;
  bottom: 0;
  border-radius: 10px 10px 0 0;
  background: #60a5fa;
}

.lu-exp-door-frame i {
  position: absolute;
  right: 28px;
  top: 56%;
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: #f59e0b;
}

.lu-exp-map {
  position: relative;
  border-radius: 16px;
  background:
    linear-gradient(120deg, transparent 44%, rgba(34, 197, 94, 0.22) 45% 54%, transparent 55%),
    linear-gradient(35deg, transparent 42%, rgba(59, 130, 246, 0.18) 43% 55%, transparent 56%),
    #f8fafc;
}

.lu-exp-map .pin {
  position: absolute;
  width: 24px;
  height: 24px;
  border-radius: 999px;
  background: #ef4444;
}

.lu-exp-map .start {
  left: 12%;
  top: 70%;
}

.lu-exp-map .end {
  right: 12%;
  top: 24%;
  background: #2563eb;
}

.lu-exp-map span {
  position: absolute;
  left: 15%;
  top: 60%;
  height: 10px;
  border-radius: 999px;
  background: #14b8a6;
  transform: rotate(-19deg);
  transform-origin: left center;
}

.lu-exp-map b {
  position: absolute;
  left: 12%;
  bottom: 16px;
}

.lu-exp-map em {
  position: absolute;
  right: 10%;
  top: 18px;
}

html[lang="en"] .lu-case-head strong,
html[lang="en"] .lu-case-result,
html[lang="en"] .lu-case-metrics b,
html[lang="en"] .lu-exp-story > strong,
html[lang="en"] .lu-exp-story p {
  overflow-wrap: anywhere;
  line-height: 1.25;
}

html[lang="en"] .lu-case-grid {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

html[lang="en"] .lu-case {
  min-height: 500px;
}

html[lang="en"] .lu-case-controls {
  grid-template-columns: minmax(0, 1fr);
}

@media (max-width: 980px) {
  .lu-lab,
  .lu-exp-workbench {
    grid-template-columns: 1fr;
  }

  .lu-chain,
  .lu-case-grid {
    grid-template-columns: 1fr;
  }

  .lu-lab-readout,
  .lu-case-metrics {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  .lu-topic .gt-nav,
  .lu-topic-layout .gt-nav {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .lu-case-controls {
    grid-template-columns: 1fr;
  }
}