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

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

.fa-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);
}

.fa-exp-story {
  display: grid;
  gap: 12px;
  align-content: start;
  padding: 18px;
  border: 1px solid rgba(79, 70, 229, 0.22);
  border-radius: 16px;
  background: linear-gradient(145deg, #ffffff, #eef2ff);
  box-shadow: 0 16px 34px rgba(67, 56, 202, 0.08);
}

.fa-exp-story > span {
  width: fit-content;
  padding: 5px 10px;
  border-radius: 999px;
  color: #4338ca;
  background: rgba(79, 70, 229, 0.12);
  font-size: 0.78rem;
  font-weight: 950;
}

.fa-exp-story > strong {
  color: #102033;
  font-size: 1.08rem;
}

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

.fa-exp-board,
.fa-common-visual,
.fa-line-visual,
.fa-case-visual {
  min-height: 220px;
  border: 1px solid rgba(190, 202, 222, 0.82);
  border-radius: 16px;
  padding: 16px;
  background:
    linear-gradient(rgba(255, 255, 255, 0.86), rgba(255, 255, 255, 0.86)),
    repeating-linear-gradient(0deg, rgba(76, 131, 240, 0.06) 0 1px, transparent 1px 28px),
    repeating-linear-gradient(90deg, rgba(76, 131, 240, 0.06) 0 1px, transparent 1px 28px);
}

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

.fa-exp-panels,
.fa-lab-board {
  display: grid;
  gap: 12px;
}

.fa-exp-panels section,
.fa-lab-board section {
  display: grid;
  gap: 8px;
  padding: 12px;
  border: 1px solid rgba(148, 163, 184, 0.28);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.94);
}

.fa-exp-panels section.is-common,
.fa-lab-board section.is-common {
  border-color: rgba(20, 184, 166, 0.4);
  background: rgba(240, 253, 250, 0.9);
}

.fa-strip,
.fa-common-strip {
  display: grid;
  grid-template-columns: repeat(var(--cols), minmax(0, 1fr));
  gap: 4px;
  min-height: 42px;
}

.fa-strip i,
.fa-common-strip i {
  display: block;
  min-width: 0;
  min-height: 34px;
  border-radius: 8px;
  border: 1px solid rgba(148, 163, 184, 0.32);
  background: #e2e8f0;
}

.fa-strip.left i.is-on,
.fa-common-strip i.is-left,
.fa-common-strip i.is-base {
  background: #60a5fa;
  border-color: rgba(37, 99, 235, 0.35);
}

.fa-strip.right i.is-on,
.fa-common-strip i.is-right {
  background: #f59e0b;
  border-color: rgba(217, 119, 6, 0.35);
}

.fa-common-strip i.is-result {
  background: #22c55e;
  border-color: rgba(22, 163, 74, 0.35);
}

.fa-common-strip i.is-removed {
  background:
    linear-gradient(135deg, transparent 42%, rgba(185, 28, 28, 0.82) 44%, rgba(185, 28, 28, 0.82) 56%, transparent 58%),
    #fecaca;
  border-color: rgba(220, 38, 38, 0.34);
}

.fa-common-strip i.ghost {
  opacity: 0.56;
}

.fa-equation {
  padding: 12px;
  border-radius: 12px;
  color: #172033;
  background: #eef2ff;
  font-weight: 950;
  line-height: 1.55;
}

.fa-number-line {
  display: grid;
  gap: 18px;
  padding: 22px 18px 18px;
}

.fa-line-track {
  position: relative;
  height: 18px;
  border-radius: 999px;
  background: #dbe4f0;
}

.fa-line-track span {
  position: absolute;
  inset-block: 0;
  border-radius: 999px;
}

.fa-line-track .first {
  left: 0;
  background: #60a5fa;
}

.fa-line-track .second {
  background: #f59e0b;
}

.fa-line-track .mark {
  position: absolute;
  top: 26px;
  color: #475569;
  font-size: 0.8rem;
}

.fa-line-track .start {
  left: 0;
}

.fa-line-track .one {
  right: 0;
}

.fa-line-track .point {
  position: absolute;
  top: -38px;
  transform: translateX(-50%);
  padding: 4px 8px;
  border-radius: 999px;
  color: #fff;
  background: #172033;
  font-style: normal;
  font-weight: 950;
  white-space: nowrap;
}

.fa-line-track .point.total {
  background: #0f766e;
}

.fa-line-ticks {
  display: grid;
  grid-template-columns: repeat(var(--cols), minmax(0, 1fr));
  align-items: start;
}

.fa-line-ticks i {
  min-height: 18px;
  border-left: 1px solid rgba(71, 85, 105, 0.3);
  color: #64748b;
  font-style: normal;
  font-size: 0.72rem;
}

.fa-case-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.fa-case {
  display: grid;
  gap: 12px;
  padding: 14px;
  border: 1px solid rgba(190, 202, 222, 0.78);
  border-radius: 16px;
  background: #fff;
}

.fa-case-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 6px 10px;
  align-items: start;
}

.fa-case-head span {
  grid-column: 1 / -1;
  width: fit-content;
  padding: 4px 10px;
  border-radius: 999px;
  color: #4338ca;
  background: rgba(79, 70, 229, 0.11);
  font-size: 0.78rem;
  font-weight: 950;
}

.fa-case-head strong {
  color: #111827;
  font-size: 1.05rem;
}

.fa-case-head em {
  padding: 5px 10px;
  border-radius: 999px;
  color: #fff;
  background: #172033;
  font-style: normal;
  font-size: 0.78rem;
  font-weight: 950;
  white-space: nowrap;
}

.fa-case-controls {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.fa-case-controls label {
  display: grid;
  gap: 6px;
  min-width: 0;
  padding: 10px;
  border: 1px solid rgba(190, 202, 222, 0.78);
  border-radius: 12px;
  color: #475569;
  font-size: 0.82rem;
  font-weight: 900;
  background: #f8fafc;
}

.fa-case-controls output,
.fa-case-controls b {
  color: #0f172a;
  font-size: 1rem;
}

.fa-case-visual {
  min-height: 190px;
  overflow: hidden;
}

.fa-case-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.fa-case-metrics span {
  display: grid;
  gap: 4px;
  padding: 9px 10px;
  border-radius: 12px;
  color: #64748b;
  background: #f1f5f9;
  font-size: 0.78rem;
  font-weight: 900;
}

.fa-case-metrics b {
  color: #111827;
  font-size: 0.92rem;
}

.fa-case-result {
  min-height: 74px;
  padding: 12px;
  border-radius: 12px;
  color: #334155;
  font-weight: 850;
  line-height: 1.58;
  background: #f8fafc;
}

.fa-pizza-scene,
.fa-chocolate-scene,
.fa-juice-scene,
.fa-track-scene,
.fa-clock-scene,
.fa-ribbon-scene,
.fa-garden-scene,
.fa-money-scene,
.fa-music-scene,
.fa-battery-scene,
.fa-recipe-scene,
.fa-book-scene {
  display: grid;
  gap: 10px;
}

.fa-pizza-scene {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: center;
}

.fa-pizza-scene section {
  display: grid;
  gap: 6px;
  padding: 10px;
  border-radius: 14px;
  background: #fff7ed;
}

.fa-pizza-scene strong {
  grid-column: 1 / -1;
  padding: 8px 10px;
  border-radius: 12px;
  color: #7c2d12;
  background: #ffedd5;
  text-align: center;
}

.fa-strip.pizza-a i,
.fa-strip.pizza-b i {
  min-height: 26px;
  border-radius: 999px 999px 7px 7px;
}

.fa-strip.pizza-a i.is-on {
  background: #f97316;
}

.fa-strip.pizza-b i.is-on {
  background: #84cc16;
}

.fa-chocolate-scene .fa-common-strip i {
  min-height: 30px;
  border-radius: 5px;
  background: #d6b692;
}

.fa-chocolate-scene .fa-common-strip i.is-result {
  background: #7c3f18;
}

.fa-chocolate-scene .fa-common-strip i.is-removed {
  background:
    linear-gradient(135deg, transparent 42%, rgba(255, 255, 255, 0.72) 44%, rgba(255, 255, 255, 0.72) 56%, transparent 58%),
    #b45309;
}

.fa-cup,
.fa-measure {
  position: relative;
  width: 92px;
  height: 138px;
  margin: 0 auto;
  border: 4px solid #94a3b8;
  border-radius: 12px 12px 24px 24px;
  overflow: hidden;
  background: #fff;
}

.fa-cup span,
.fa-measure span {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
}

.fa-cup .a {
  background: rgba(249, 115, 22, 0.64);
}

.fa-cup .b,
.fa-measure span {
  background: rgba(59, 130, 246, 0.54);
}

.fa-cup b,
.fa-measure b {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: #0f172a;
  font-weight: 950;
}

.fa-track {
  position: relative;
  min-height: 62px;
  border: 4px solid #475569;
  border-radius: 999px;
  background: #e2e8f0;
}

.fa-track span {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  border-radius: 999px;
  background: linear-gradient(90deg, #22c55e, #14b8a6);
}

.fa-track i {
  position: absolute;
  top: 50%;
  width: 24px;
  height: 24px;
  transform: translate(-50%, -50%);
  border: 4px solid #fff;
  border-radius: 999px;
  background: #ef4444;
  box-shadow: 0 4px 10px rgba(15, 23, 42, 0.2);
}

.fa-clock {
  display: grid;
  place-items: center;
  width: 118px;
  height: 118px;
  margin: 0 auto;
  border: 7px solid #334155;
  border-radius: 999px;
  background: conic-gradient(#60a5fa var(--pct), #f8fafc 0);
}

.fa-clock b {
  display: grid;
  place-items: center;
  width: 68px;
  height: 68px;
  border-radius: 999px;
  background: #fff;
  color: #0f172a;
  font-weight: 950;
}

.fa-clock-scene span {
  text-align: center;
  font-weight: 950;
}

.fa-ribbon-scene .fa-common-strip i {
  min-height: 28px;
  border-radius: 4px 12px 12px 4px;
}

.fa-garden-scene .fa-common-strip {
  padding: 10px;
  border-radius: 14px;
  background: #dcfce7;
}

.fa-garden-scene .fa-common-strip i {
  min-height: 34px;
  border-radius: 6px;
  background: #bbf7d0;
}

.fa-garden-scene .fa-common-strip i.is-left,
.fa-garden-scene .fa-common-strip i.is-right {
  background: #22c55e;
}

.fa-money-scene .fa-common-strip i {
  min-height: 32px;
  border-radius: 999px;
  background: #d1fae5;
}

.fa-money-scene .fa-common-strip i.is-result {
  background: #10b981;
}

.fa-music-scene .fa-common-strip i {
  min-height: 38px;
  border-radius: 8px;
  background: #e9d5ff;
}

.fa-music-scene .fa-common-strip i.is-left,
.fa-music-scene .fa-common-strip i.is-right {
  background: #a855f7;
}

.fa-battery {
  position: relative;
  min-height: 54px;
  border: 4px solid #475569;
  border-radius: 14px;
  background: #fff;
  overflow: hidden;
}

.fa-battery::after {
  content: "";
  position: absolute;
  right: -11px;
  top: 14px;
  width: 8px;
  height: 24px;
  border-radius: 0 6px 6px 0;
  background: #475569;
}

.fa-battery span {
  position: absolute;
  inset-block: 0;
  left: 0;
  background: #22c55e;
}

.fa-battery b {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: #0f172a;
  font-weight: 950;
}

.fa-recipe-scene {
  place-items: center;
}

.fa-book-scene section {
  display: grid;
  gap: 10px;
  padding: 14px;
  border-radius: 16px;
  background:
    linear-gradient(90deg, transparent 49%, rgba(100, 116, 139, 0.3) 50%, transparent 51%),
    #fff7ed;
}

.fa-book-scene .fa-common-strip i {
  min-height: 30px;
  border-radius: 4px;
}

.fa-chocolate-scene strong,
.fa-track-scene strong,
.fa-ribbon-scene strong,
.fa-money-scene strong,
.fa-book-scene strong,
.fa-garden-scene span,
.fa-music-scene span,
.fa-recipe-scene strong {
  padding: 8px 10px;
  border-radius: 12px;
  color: #334155;
  background: rgba(248, 250, 252, 0.94);
  font-weight: 950;
  text-align: center;
}

@media (max-width: 1180px) {
  .fa-case-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 860px) {
  .fa-topic .gt-nav,
  .fa-exp-workbench,
  .fa-case-grid,
  .fa-case-controls,
  .fa-case-metrics,
  .fa-pizza-scene {
    grid-template-columns: 1fr;
  }

  .fa-line-track .point {
    font-size: 0.68rem;
  }
}