.tabs {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
}
.tabs button {
  min-width: 0;
  min-height: 46px;
  padding: 12px 4px;
}
#number-path {
  max-width: 100%;
  width: 260px;
}
.relation-toolbar,
.calculation-toolbar {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
  margin: 0 0 20px;
  font-size: 13px;
  color: #547365;
}
.relation-toolbar label,
.calculation-toolbar label {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.relation-toolbar select,
.calculation-toolbar select,
#number-path,
#division-level {
  font-size: 16px;
  min-height: 44px;
}
.relationship-work {
  max-width: 620px;
  margin: auto;
}
.relationship-work h3 {
  margin: 0 0 12px;
  font-size: 19px;
}
.linked-amounts {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 22px;
  margin: 15px 0;
  font-size: 28px;
  color: #38765e;
  font-variant-numeric: tabular-nums;
}
.linked-amounts > span {
  color: #8a9e94;
  font-size: 21px;
}
.relation-boards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  max-width: 464px;
  margin: auto;
}
.relation-boards > div {
  min-width: 0;
}
.relation-boards .visual-caption {
  flex-direction: column;
  align-items: start;
  gap: 3px;
  min-height: 52px;
  margin: 0 0 8px;
}
.relation-boards .visual-caption strong {
  font-size: 17px;
}
.relation-pieces,
.relation-hundred {
  display: grid;
  width: 100%;
  aspect-ratio: 1;
  background: #c7dcd2;
  padding: 4px;
  gap: 2px;
}
.relation-pieces {
  grid-template-columns: repeat(var(--columns, 2), minmax(0, 1fr));
}
.relation-pieces > *,
.relation-hundred > i {
  background: white;
  border: 0;
  border-radius: 0;
  padding: 0;
  min-width: 0;
  min-height: 0;
  display: block;
}
.relation-pieces > button {
  touch-action: manipulation;
}
.relation-pieces > .selected,
.relation-hundred > .selected {
  background: #3f8c73;
}
.relation-hundred {
  grid-template-columns: repeat(10, minmax(0, 1fr));
}
.relationship-work .range-label,
.relationship-work input[type="range"],
.relation-number-line {
  max-width: 464px;
  margin-left: auto;
  margin-right: auto;
}
.relationship-work input[type="range"] {
  display: block;
}
#relation-equality {
  font-size: 17px;
  text-align: center;
  font-variant-numeric: tabular-nums;
}
.relation-number-line {
  display: flex;
  gap: 12px;
  align-items: center;
  font-size: 13px;
  color: #5e7c6a;
}
.relation-number-line > div {
  position: relative;
  flex: 1;
  height: 3px;
  background: #abc5b6;
}
#relation-marker {
  position: absolute;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: #ad7b36;
  transform: translate(-50%, -4px);
}
.recurring-note {
  border-top: 1px solid #dce7e0;
  margin-top: 20px;
  padding-top: 14px;
  font-size: 13px;
  color: #617b6b;
}
.recurring-note summary,
.custom-division summary {
  cursor: pointer;
  min-height: 40px;
}
.custom-division {
  margin: 0 0 18px;
  color: #617b6b;
  font-size: 13px;
}
.custom-division .custom-problem {
  border-top: 0;
  padding-top: 0;
  align-items: center;
}
.custom-division .custom-problem input {
  width: 100px;
  font-size: 16px;
}
.operation-workspace .visual-caption {
  align-items: start;
  flex-wrap: wrap;
}
.operation-workspace .visual-caption strong {
  font-size: 20px;
  overflow-wrap: anywhere;
}
.operation-fields {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 16px 0;
}
.operation-fields label {
  display: grid;
  gap: 7px;
  flex: 1 1 100px;
  max-width: 160px;
  min-width: 0;
  font-size: 13px;
  color: #5c7c68;
}
.operation-fields input {
  height: 50px;
  width: 100%;
  min-width: 0;
  border: 1px solid #b7d4c2;
  border-radius: 5px;
  background: #f8fcfa;
  color: #39775d;
  font-size: 24px;
  padding: 8px;
}
.operation-workspace h3 {
  font-size: 18px;
  margin: 14px 0;
}
.operation-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.operation-next {
  margin-left: 0;
}
.operation-expression {
  display: block;
  font-size: 23px;
  line-height: 1.6;
  text-align: center;
  color: #3a7764;
  margin: 18px 0;
  font-variant-numeric: tabular-nums;
  overflow-wrap: anywhere;
}
.operation-diagram {
  width: 100%;
  min-width: 0;
}
.quantity-bar {
  margin: 18px 0;
}
.quantity-label {
  font-size: 14px;
  color: #4d786b;
  display: block;
  margin: 0 0 7px;
}
.quantity-track {
  display: grid;
  grid-template-columns: repeat(var(--parts), minmax(0, 1fr));
  gap: 1px;
  border: 1px solid #a6c5c8;
  height: 42px;
  background: #c4d7d8;
  padding: 2px;
}
.quantity-track > i {
  background: white;
}
.quantity-track > i.painted {
  background: #558ba5;
}
.second-quantity > i.painted {
  background: #c09953;
}
.fraction-product-grid {
  display: grid;
  grid-template-columns: repeat(var(--columns), minmax(0, 1fr));
  grid-template-rows: repeat(var(--rows), minmax(0, 1fr));
  aspect-ratio: 1;
  max-width: 280px;
  margin: 16px auto;
  gap: 3px;
  background: #d5e3e0;
  padding: 4px;
}
.fraction-product-grid > i {
  background: white;
}
.fraction-product-grid > .horizontal-paint {
  background: #b5d1e2;
}
.fraction-product-grid > .vertical-paint {
  background: #f1dbaf;
}
.fraction-product-grid > .overlap-paint {
  background: #438a69;
}
.division-work {
  max-width: 360px;
  margin: 18px auto;
  width: 100%;
  font-variant-numeric: tabular-nums;
  font-family: ui-monospace, "Courier New", monospace;
}
.division-row {
  display: grid;
  grid-template-columns: 42px repeat(var(--division-digits), minmax(0, 1fr));
  min-height: 34px;
  align-items: center;
  font-size: 23px;
  line-height: 1.3;
  text-align: center;
}
.division-row > span {
  min-width: 0;
  position: relative;
}
.division-sign {
  text-align: right;
  padding-right: 8px;
  font-size: 18px;
  color: #668879;
}
.division-dividend > span:not(:first-child) {
  border-top: 2px solid #759783;
  padding-top: 5px;
}
.division-dividend > span:nth-child(2) {
  border-left: 2px solid #759783;
  border-top-left-radius: 8px;
}
.division-product > span:not(:first-child) {
  border-bottom: 1px solid #a5bdb0;
  padding-bottom: 4px;
  color: #73998a;
}
.division-remainder {
  color: #5d8775;
}
.division-bring {
  color: #367da5;
}
.division-quotient {
  color: #2c7a60;
}
.division-row > .brought-digit {
  background: #e1eceb;
}
.decimal-break::after {
  content: ".";
  position: absolute;
  right: -4px;
  color: #a5773a;
  font-weight: 700;
}
.decimal-column {
  width: min(330px, 100%);
  margin: 24px auto;
  font-variant-numeric: tabular-nums;
  font-family: ui-monospace, "Courier New", monospace;
}
.decimal-column-row {
  display: grid;
  grid-template-columns: 24px repeat(var(--decimal-columns), minmax(0, 1fr));
  text-align: center;
  min-height: 40px;
  align-items: center;
  font-size: 25px;
  white-space: pre;
}
.decimal-column-row:last-child {
  border-bottom: 2px solid #80a18f;
  padding-bottom: 6px;
}
.decimal-alignment {
  background: #f1e3c6;
  color: #9b7339;
}
.decimal-moves {
  display: grid;
  gap: 14px;
  text-align: center;
  font-size: 21px;
  color: #608a78;
  margin: 24px 0;
}
.scale-arrow {
  display: block;
  text-align: center;
  color: #9b783d;
  font-size: 15px;
}
.scene-operation {
  justify-content: flex-start;
  overflow: auto;
}
.scene-operation .operation-expression {
  font-size: 21px;
}
.scene-operation .fraction-product-grid {
  max-height: 200px;
  max-width: 200px;
}
.scene-operation .division-visual {
  width: 100%;
}
.scene-operation .quantity-track {
  height: 32px;
}
@media (max-width: 760px) {
  .tabs button {
    font-size: 13px;
  }
  .relation-boards {
    gap: 16px;
  }
  .relationship-work h3 {
    font-size: 17px;
  }
  .linked-amounts {
    font-size: 26px;
    margin: 12px 0;
  }
  .operation-workspace .visual-column {
    padding: 16px;
  }
  .division-row {
    font-size: 21px;
  }
  .operation-expression {
    font-size: 21px;
  }
  .decimal-column-row {
    font-size: 23px;
  }
  .number-heading {
    padding-bottom: 14px;
  }
  #number-path {
    width: 100%;
  }
}