.problem-page {
  color: var(--slate-700);
  background: #fff;
}

.problem-page *,
.problem-page *::before,
.problem-page *::after {
  box-sizing: border-box;
}

.problem-shell {
  width: min(100% - 40px, 1040px);
  margin-inline: auto;
}

.problem-breadcrumb {
  padding-top: 24px;
  font-size: 14px;
}

.problem-breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.problem-breadcrumb li + li::before {
  margin-right: 8px;
  color: var(--slate-500);
  content: "/";
}

.problem-breadcrumb a,
.problem-text-link {
  color: var(--blue-700);
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.problem-hero {
  max-width: 900px;
  padding: 54px 0 32px;
}

.problem-kicker,
.problem-step-label {
  margin: 0 0 9px;
  color: var(--blue-700);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: .04em;
}

.problem-hero h1 {
  max-width: 850px;
  margin: 0;
  color: var(--navy-950);
  font-size: clamp(2.15rem, 5vw, 3.35rem);
  letter-spacing: -.045em;
  line-height: 1.28;
}

.problem-lead {
  max-width: 780px;
  margin: 22px 0 0;
  color: var(--slate-700);
  font-size: 17px;
  line-height: 1.9;
}

.problem-safety {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 16px;
  margin: 0 0 56px;
  padding: 22px 24px;
  border: 1px solid #e8cda6;
  border-radius: 10px;
  background: #fffaf3;
}

.problem-safety-icon {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border: 2px solid var(--orange-700);
  border-radius: 50%;
  color: var(--orange-700);
  font-weight: 900;
}

.problem-safety h2 {
  margin: 0 0 7px;
  color: #71410f;
  font-size: 19px;
}

.problem-safety p,
.problem-safety small {
  display: block;
  margin: 0;
  color: #684621;
  font-size: 15px;
  line-height: 1.75;
}

.problem-safety.is-danger {
  border-color: #e2aaaa;
  background: #fff7f7;
}

.problem-safety.is-danger .problem-safety-icon {
  border-color: #b42318;
  color: #b42318;
}

.problem-safety.is-danger h2,
.problem-safety.is-danger p,
.problem-safety.is-danger small {
  color: #6f1d1b;
}

.problem-safety-button {
  margin-top: 14px;
}

.problem-fixed-summary {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 12px;
  overflow: hidden;
  border: 1px solid var(--slate-200);
  border-radius: 10px;
  background: var(--slate-200);
}

.problem-fixed-summary > div {
  padding: 18px 20px;
  background: #fff;
}

.problem-fixed-summary dt {
  color: var(--slate-600);
  font-size: 14px;
  font-weight: 800;
}

.problem-fixed-summary dd {
  margin: 5px 0 0;
  color: var(--navy-950);
  font-size: 21px;
  font-weight: 900;
}

.problem-scope-note {
  margin: 0 0 52px;
  color: var(--slate-600);
  line-height: 1.75;
}

.problem-safety small {
  margin-top: 7px;
  font-weight: 700;
}

.problem-section-heading {
  max-width: 760px;
  margin-bottom: 25px;
}

.problem-section-heading h2,
.problem-check-content h2,
.problem-repair-stage h2,
.problem-feedback h2 {
  margin: 0;
  color: var(--navy-950);
  font-size: clamp(1.55rem, 3.2vw, 2rem);
  letter-spacing: -.025em;
  line-height: 1.4;
}

.problem-section-heading > p:last-child {
  margin: 10px 0 0;
  color: var(--slate-600);
  line-height: 1.75;
}

.problem-situation {
  padding-bottom: 60px;
}

.problem-situation-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.problem-choice {
  display: flex;
  min-height: 66px;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 18px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
  color: var(--navy-950);
  background: #fff;
  font-weight: 800;
  text-decoration: none;
  transition: border-color .18s ease, background-color .18s ease;
}

.problem-choice:hover,
.problem-choice:focus-visible,
.problem-choice.is-selected {
  border-color: var(--blue-500);
  background: var(--blue-50);
}

.problem-inline-note {
  margin-top: 18px;
  padding: 18px 20px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
  background: var(--blue-50);
}

.problem-inline-note h3,
.problem-diagnosis-result h3 {
  margin: 0 0 7px;
  color: var(--navy-950);
  font-size: 18px;
}

.problem-inline-note p,
.problem-diagnosis-result p {
  margin: 0 0 10px;
  line-height: 1.75;
}

.problem-diagnosis {
  scroll-margin-top: 24px;
  margin-bottom: 72px;
  padding: 30px;
  border: 1px solid var(--slate-200);
  border-radius: 12px;
  background: var(--blue-50);
}

.problem-diagnosis-form {
  display: grid;
  gap: 20px;
}

.problem-form-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.problem-form-grid.is-single {
  grid-template-columns: minmax(0, 420px);
}

.problem-form-grid label,
.problem-age-form label {
  display: grid;
  gap: 8px;
  color: var(--navy-950);
  font-weight: 800;
}

.problem-form-grid label span small {
  color: var(--slate-600);
  font-size: 13px;
}

.problem-form-grid input,
.problem-form-grid select,
.problem-age-row select {
  width: 100%;
  min-height: 50px;
  padding: 10px 13px;
  border: 1px solid #b8cedb;
  border-radius: 8px;
  color: var(--navy-950);
  background: #fff;
  font: inherit;
}

.problem-form-grid input:focus,
.problem-form-grid select:focus,
.problem-age-row select:focus {
  border-color: var(--blue-700);
  outline: 3px solid rgba(7, 138, 210, .16);
}

.problem-button {
  display: inline-flex;
  min-height: 48px;
  width: fit-content;
  align-items: center;
  justify-content: center;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: 8px;
  font: inherit;
  font-weight: 800;
  line-height: 1.4;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

.problem-button-primary {
  border-color: var(--blue-700);
  color: #fff;
  background: var(--blue-700);
}

.problem-button-secondary {
  border-color: #a9c7d8;
  color: var(--navy-950);
  background: #fff;
}

.problem-button:hover,
.problem-button:focus-visible,
.problem-method-grid button:hover,
.problem-method-grid button:focus-visible {
  filter: brightness(.94);
  outline: 3px solid rgba(7, 138, 210, .18);
  outline-offset: 2px;
}

.problem-diagnosis-result {
  margin-top: 22px;
  padding: 20px;
  border: 1px solid #b7d9ea;
  border-radius: 9px;
  background: #fff;
}

.problem-diagnosis-result .problem-button + p,
.problem-diagnosis-result p + .problem-button + p {
  margin-top: 18px;
}

.problem-causes {
  margin-bottom: 72px;
  padding-top: 4px;
}

.problem-causes ul {
  display: grid;
  gap: 9px;
  margin: 0 0 18px;
  padding-left: 1.35em;
  color: var(--navy-800);
  line-height: 1.7;
}

.problem-causes > p {
  margin: 0;
  color: var(--slate-600);
  line-height: 1.75;
}

.problem-flow-wrap {
  border-block: 1px solid var(--slate-200);
  background: #f8fbfd;
}

.problem-flow {
  padding-block: 72px;
}

.problem-flow-heading {
  margin-bottom: 44px;
}

.problem-check-step {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 24px;
  scroll-margin-top: 24px;
  padding: 0 0 48px;
}

.problem-check-step + .problem-check-step {
  padding-top: 48px;
  border-top: 1px solid var(--slate-200);
}

.problem-check-number {
  display: grid;
  width: 46px;
  height: 46px;
  place-items: center;
  border-radius: 50%;
  color: #fff;
  background: var(--navy-950);
  font-size: 19px;
  font-weight: 900;
}

.problem-check-content > p {
  margin: 10px 0 0;
  line-height: 1.8;
}

.problem-check-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 24px;
  margin: 20px 0;
  padding: 0;
  list-style: none;
}

.problem-check-list li {
  position: relative;
  padding-left: 27px;
  line-height: 1.65;
}

.problem-check-list li::before {
  position: absolute;
  top: .18em;
  left: 0;
  display: grid;
  width: 20px;
  height: 20px;
  place-items: center;
  border: 1px solid #9fc3d6;
  border-radius: 50%;
  color: var(--blue-700);
  content: "✓";
  font-size: 12px;
  font-weight: 900;
}

.problem-step-note {
  padding: 14px 16px;
  border-left: 3px solid var(--blue-700);
  color: var(--navy-800);
  background: #fff;
  font-weight: 700;
}

.problem-found-action {
  margin: 20px 0 12px;
}

.problem-found-action h3 {
  margin: 0 0 6px;
  color: var(--navy-950);
  font-size: 16px;
}

.problem-found-action p {
  margin: 0;
  line-height: 1.75;
}

.problem-repair-stage {
  margin-top: 12px;
  padding: 30px;
  border: 1px solid #e4b7b7;
  border-radius: 10px;
  background: #fffafa;
}

.problem-repair-stage > p:not(.problem-step-label) {
  max-width: 780px;
  margin: 12px 0 22px;
  line-height: 1.8;
}

.problem-lower-content {
  padding-block: 72px;
}

.problem-errors,
.problem-replace,
.problem-feedback {
  padding-bottom: 64px;
}

.problem-related {
  margin-bottom: 64px;
  padding: 24px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
  background: #fff;
}

.problem-related h2 {
  margin: 0;
  color: var(--navy-950);
  font-size: 1.35rem;
}

.problem-related ul {
  display: grid;
  gap: 9px;
  margin: 14px 0 0;
  padding-left: 1.2em;
}

.problem-related a {
  color: var(--blue-700);
  font-weight: 800;
  text-underline-offset: 3px;
}

.problem-error-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.problem-error-grid article {
  padding: 22px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
}

.problem-error-grid article > p:first-child {
  margin: 0;
  color: var(--slate-600);
  font-size: 14px;
  font-weight: 800;
}

.problem-error-grid h3 {
  margin: 5px 0 10px;
  color: var(--navy-950);
  font-size: 26px;
}

.problem-error-grid article > p:not(:first-child) {
  margin: 0;
  line-height: 1.7;
}

.problem-error-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  margin-top: 15px;
}

.problem-replace {
  padding-top: 64px;
  border-top: 1px solid var(--slate-200);
}

.problem-age-form {
  max-width: 760px;
  padding: 24px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
  background: var(--blue-50);
}

.problem-age-row {
  display: grid;
  grid-template-columns: minmax(180px, 240px) auto;
  gap: 12px;
  margin-top: 10px;
}

.problem-feedback {
  padding-top: 48px;
  border-top: 1px solid var(--slate-200);
}

.problem-feedback-actions {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}

.problem-feedback-method {
  margin-top: 24px;
}

.problem-feedback-method > p {
  color: var(--navy-950);
  font-weight: 800;
}

.problem-method-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.problem-method-grid button {
  min-height: 44px;
  padding: 8px 14px;
  border: 1px solid #a9c7d8;
  border-radius: 999px;
  color: var(--navy-950);
  background: #fff;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.problem-method-grid button.is-selected,
.problem-feedback-actions button.is-selected {
  border-color: var(--blue-700);
  color: #fff;
  background: var(--blue-700);
}

.problem-feedback-status {
  min-height: 1.5em;
  margin: 14px 0 0;
  color: var(--green-700);
  font-weight: 700;
}

.problem-sources {
  margin-bottom: 8px;
  padding: 18px 20px;
  border: 1px solid var(--slate-200);
  border-radius: 9px;
  background: #fff;
}

.problem-sources summary {
  color: var(--navy-950);
  font-weight: 800;
  cursor: pointer;
}

.problem-sources p {
  color: var(--slate-600);
  font-size: 14px;
}

.problem-sources ul {
  display: grid;
  gap: 10px;
  margin: 14px 0 0;
  padding-left: 20px;
}

.problem-sources li {
  line-height: 1.65;
}

.problem-sources li span {
  margin-right: 8px;
  color: var(--navy-950);
  font-weight: 800;
}

.problem-sources a {
  color: var(--blue-700);
}

@media (max-width: 760px) {
  .problem-shell {
    width: min(100% - 28px, 1040px);
  }

  .problem-breadcrumb {
    padding-top: 16px;
  }

  .problem-hero {
    padding: 36px 0 24px;
  }

  .problem-hero h1 {
    font-size: clamp(1.85rem, 9vw, 2.45rem);
  }

  .problem-lead {
    margin-top: 16px;
    font-size: 16px;
    line-height: 1.8;
  }

  .problem-safety {
    grid-template-columns: 34px 1fr;
    gap: 12px;
    margin-bottom: 42px;
    padding: 18px 16px;
  }

  .problem-safety-icon {
    width: 30px;
    height: 30px;
  }

  .problem-situation {
    padding-bottom: 44px;
  }

  .problem-situation-grid,
  .problem-form-grid,
  .problem-check-list,
  .problem-error-grid {
    grid-template-columns: 1fr;
  }

  .problem-fixed-summary {
    grid-template-columns: 1fr;
  }

  .problem-choice {
    min-height: 58px;
  }

  .problem-diagnosis {
    margin-bottom: 52px;
    padding: 22px 16px;
  }

  .problem-causes {
    margin-bottom: 52px;
  }

  .problem-diagnosis-form > .problem-button {
    width: 100%;
  }

  .problem-flow {
    padding-block: 52px;
  }

  .problem-flow-heading {
    margin-bottom: 32px;
  }

  .problem-check-step {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 13px;
    padding-bottom: 36px;
  }

  .problem-check-step + .problem-check-step {
    padding-top: 36px;
  }

  .problem-check-number {
    width: 36px;
    height: 36px;
    font-size: 16px;
  }

  .problem-check-content h2 {
    font-size: 1.35rem;
  }

  .problem-check-list {
    gap: 10px;
  }

  .problem-repair-stage {
    padding: 22px 18px;
  }

  .problem-repair-stage .problem-button,
  .problem-age-row .problem-button {
    width: 100%;
  }

  .problem-lower-content {
    padding-block: 52px;
  }

  .problem-errors,
  .problem-replace,
  .problem-feedback {
    padding-bottom: 48px;
  }

  .problem-replace {
    padding-top: 48px;
  }

  .problem-age-form {
    padding: 18px 16px;
  }

  .problem-age-row {
    grid-template-columns: 1fr;
  }

  .problem-feedback-actions .problem-button {
    flex: 1;
  }
}

@media (max-width: 360px) {
  .problem-shell {
    width: min(100% - 22px, 1040px);
  }

  .problem-check-step {
    grid-template-columns: 1fr;
  }

  .problem-check-number {
    margin-bottom: -2px;
  }
}