.physics-solution {
  border-color: #0284c7;
  box-shadow: 0 8px 20px rgba(3, 105, 161, 0.12);
}

.physics-solution summary {
  gap: 14px;
  background: linear-gradient(135deg, #0369a1, #0284c7);
  color: #fff;
  transition: filter 0.18s ease;
}

.physics-solution summary:hover {
  filter: brightness(1.08);
}

.physics-solution summary:focus-visible {
  outline: 4px solid rgba(14, 165, 233, 0.28);
  outline-offset: 3px;
}

.physics-solution summary::after {
  content: none;
}

.physics-solution-cta {
  display: grid;
  gap: 3px;
}

.physics-solution-cta strong {
  font-size: 1.04rem;
}

.physics-solution summary small {
  margin-left: 0;
  color: rgba(255, 255, 255, 0.88);
}

.physics-solution-toggle {
  display: grid;
  flex: 0 0 34px;
  width: 34px;
  height: 34px;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.55);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  font-size: 1.55rem;
  line-height: 1;
  transition: transform 0.2s ease;
}

.physics-solution-close-label {
  display: none;
}

.physics-solution[open] .physics-solution-open-label {
  display: none;
}

.physics-solution[open] .physics-solution-close-label {
  display: inline;
}

.physics-solution[open] .physics-solution-toggle {
  transform: rotate(45deg);
}

.physics-test-card-official {
  border: 2px solid #22c55e;
  background: linear-gradient(145deg, #064e3b 0%, #047857 55%, #16a34a 100%);
  box-shadow: 0 24px 64px rgba(4, 120, 87, 0.28);
}

.physics-test-card-official h2,
.physics-test-card-official strong {
  color: #fff;
}

.physics-test-card-official p {
  color: rgba(255, 255, 255, 0.92);
}

.physics-test-card-official small {
  color: rgba(255, 255, 255, 0.82);
}

.physics-test-card-official .ona-certificate-badge {
  border-color: rgba(255, 255, 255, 0.55);
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
}

.physics-share-invitation {
  margin-top: 16px;
  padding: 14px 16px;
  border: 1px solid #a7f3d0;
  border-radius: 13px;
  background: linear-gradient(135deg, #ecfdf5, #f0f9ff);
  color: #064e3b;
  text-align: left;
}

.physics-share-invitation strong {
  display: block;
  margin-bottom: 4px;
  color: #047857;
  font-size: 1.02rem;
}

.physics-share-invitation p {
  margin: 0;
  line-height: 1.5;
}

#physics-share-result {
  box-shadow: 0 8px 20px rgba(2, 132, 199, 0.22);
}

@media (max-width: 700px) {
  .physics-solution summary {
    flex-wrap: nowrap;
    align-items: center;
  }

  .physics-solution summary small {
    order: initial;
    width: auto;
  }
}