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}.learning-shell .p2-fr-picture-row.is-winner .p2-fr-bar{
  outline: 4px solid #f7a84b;
  outline-offset: 2px;
}.learning-shell .p2-fr-working-row{
  margin-top: 8px;
  padding-top: 14px;
  border-top: 1px solid #dbe5f3;
}.learning-shell .p2-fr-visual-note{
  width: max-content;
  max-width: 100%;
  margin: 10px 0 0 !important;
  padding: 7px 11px;
  border-radius: 8px;
  background: #fff3dd;
  color: #6b4214;
  font-size: 14px !important;
  font-weight: 750;
  line-height: 1.45;
}.learning-shell .p2-fr-visual-note:empty{
  display: none;
}@keyframes p2-fr-reveal{
  from {
    opacity: 0.2;
    transform: translateY(7px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}.learning-shell .p2-fr-equation.is-animating,.learning-shell .p2-fr-guidance.is-animating,.learning-shell .p2-fr-whole-bar.is-animating,.learning-shell .p2-fr-comparison.is-animating,.learning-shell .p2-fr-operands.is-animating,.learning-shell .p2-fr-result-row{
  animation: p2-fr-reveal 0.28s ease-out both;
}.learning-shell .p2-fr-bar span.is-removed{
  animation: p2-fr-reveal 0.28s ease-out both;
}@media (prefers-reduced-motion: reduce){.learning-shell .p2-fr-equation.is-animating,.learning-shell .p2-fr-guidance.is-animating,.learning-shell .p2-fr-whole-bar.is-animating,.learning-shell .p2-fr-comparison.is-animating,.learning-shell .p2-fr-operands.is-animating,.learning-shell .p2-fr-result-row,.learning-shell .p2-fr-bar span.is-removed{
    animation: none;
  }
}.learning-shell .p2-fr-intro-figure{
  max-width: 900px;
  margin: 20px 0 0;
  padding: 24px;
  border: 1px solid #dbe5f3;
  border-radius: 16px;
  background: #fff;
}.learning-shell .p2-fr-intro-labels{
  display: flex;
  align-items: center;
  gap: 28px;
}.learning-shell .p2-fr-intro-labels > .p2-fr-notation{
  flex: none;
  min-width: 1.3em;
  font-size: 62px;
  font-weight: 850;
}.learning-shell .p2-fr-intro-terms{
  display: grid;
  gap: 12px;
}.learning-shell .p2-fr-intro-terms p{
  margin: 0;
  color: #344866;
  font-size: 17px;
  line-height: 1.5;
}.learning-shell .p2-fr-intro-terms strong{
  color: #142454;
}.learning-shell .p2-fr-intro-bar{
  max-width: 580px;
  height: 72px;
  margin-top: 22px;
}.learning-shell .p2-fr-intro-figure figcaption{
  margin-top: 12px;
  color: #526080;
  font-size: 15px;
  line-height: 1.5;
}@media (max-width: 620px){.learning-shell .p2-fr-intro-figure{
    padding: 18px;
  }.learning-shell .p2-fr-intro-labels{
    gap: 17px;
  }.learning-shell .p2-fr-intro-labels > .p2-fr-notation{
    font-size: 48px;
  }.learning-shell .p2-fr-intro-terms p{
    font-size: 15px;
  }.learning-shell .p2-fr-intro-bar{
    height: 58px;
  }
}.learning-shell .grade-switch{display:flex;flex-wrap:wrap;gap:10px;margin:0 0 24px}.learning-shell .grade-switch a{display:inline-block;padding:11px 17px;border:2px solid #b7cfde;border-radius:999px;background:#fff;color:#142454;font-size:16px;font-weight:800;text-decoration:none}.learning-shell .grade-switch a[aria-current="page"]{border-color:#168b87;background:#eaf7f6}.learning-shell .grade-switch a:hover,.learning-shell .grade-switch a:focus-visible{border-color:#168b87;outline-offset:3px}.learning-shell .breadcrumb a{color:#3555bd;text-decoration:underline;text-underline-offset:2px}.learning-shell .breadcrumb a[aria-current="page"]{color:#142454;font-weight:700}