.useful-page {
  padding: 72px 0;
  background: #f6f6fb;
  font-family: var(--font-main, "Space Grotesk", sans-serif);
}

.useful-page__inner {
  max-width: 1440px;
  margin: 0 auto;
}

.useful-page__head {
  margin-bottom: 28px;
}

.useful-toc {
  margin-bottom: 24px;
  padding: 16px 18px;
  background: #ffffff;
  border: 1px solid rgba(172, 173, 177, 0.18);
  border-radius: 4px;
  box-shadow: 0 12px 24px rgba(45, 47, 51, 0.05);
}

.useful-toc__title {
  margin: 0 0 10px;
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #5a5b60;
}

.useful-toc__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
}

#useful-grade-guide,
#useful-memo-title,
#useful-concrete-care {
  scroll-margin-top: 80px;
}

.useful-toc a {
  color: #bb0100;
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.useful-page h1 {
  margin: 0 0 12px;
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #2d2f33;
  max-width: 980px;
}

.useful-page > .useful-page__inner > p,
.useful-page__head p {
  margin: 0;
  color: #5a5b60;
  max-width: 900px;
  font-size: 1rem;
  line-height: 1.6;
}

.useful-table-wrap {
  background: #ffffff;
  border: 1px solid rgba(172, 173, 177, 0.18);
  box-shadow: 0 20px 40px rgba(45, 47, 51, 0.06);
  border-radius: 4px;
  overflow: hidden;
}

.useful-table {
  width: 100%;
  border-collapse: collapse;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.useful-table thead th {
  text-align: left;
  padding: 14px 16px;
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #ffffff;
  background: #bb0100;
}

.useful-table tbody td {
  padding: 14px 16px;
  border-top: 1px solid rgba(172, 173, 177, 0.2);
  color: #2d2f33;
  font-size: 0.95rem;
  line-height: 1.45;
  vertical-align: top;
}

.useful-table tbody tr:nth-child(even) td {
  background: rgba(240, 240, 246, 0.55);
}

.useful-table tbody td:first-child {
  font-weight: 800;
  color: #bb0100;
}

.useful-table tbody td:nth-child(2) {
  font-weight: 700;
}

.useful-memo {
  margin-top: 28px;
}

.useful-article {
  margin-top: 28px;
  padding: 22px 20px 24px;
  background: #ffffff;
  border: 1px solid rgba(172, 173, 177, 0.18);
  border-left: 4px solid #bb0100;
  border-radius: 4px;
  box-shadow: 0 20px 40px rgba(45, 47, 51, 0.06);
}

.useful-article h2 {
  margin: 0 0 12px;
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  font-weight: 800;
  color: #2d2f33;
}

.useful-article__lead {
  margin: 0 0 20px;
  color: #5a5b60;
  line-height: 1.6;
}

.useful-article__subheading {
  margin: 22px 0 10px;
  font-size: 1.05rem;
  font-weight: 800;
  color: #2d2f33;
}

.useful-article p {
  margin: 0 0 12px;
  color: #5a5b60;
  line-height: 1.6;
}

.useful-article__step {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid rgba(172, 173, 177, 0.22);
}

.useful-article__step h4 {
  margin: 0 0 8px;
  font-size: 0.95rem;
  font-weight: 800;
  text-transform: uppercase;
  color: #2d2f33;
}

.useful-article__list {
  margin: 8px 0 0;
  padding-left: 18px;
  color: #5a5b60;
}

.useful-article__callout {
  margin: 12px 0 0;
  padding: 12px 14px;
  background: rgba(240, 240, 246, 0.85);
  border-radius: 4px;
  border: 1px solid rgba(172, 173, 177, 0.25);
}

.useful-memo h2 {
  margin: 0 0 10px;
  font-size: clamp(1.45rem, 3vw, 2.1rem);
  font-weight: 800;
  color: #2d2f33;
}

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

.useful-card,
.useful-faq {
  background: #ffffff;
  border: 1px solid rgba(172, 173, 177, 0.18);
  border-left: 4px solid #bb0100;
  border-radius: 4px;
  padding: 16px;
  box-shadow: 0 12px 24px rgba(45, 47, 51, 0.05);
}

.useful-card--options,
.useful-faq {
  margin-top: 16px;
}

.useful-card h3,
.useful-faq h3 {
  margin: 0 0 10px;
  font-size: 1rem;
  font-weight: 800;
  text-transform: uppercase;
  color: #2d2f33;
}

.useful-card ul {
  margin: 0;
  padding-left: 18px;
  color: #5a5b60;
}

.useful-faq dt {
  font-weight: 700;
  color: #2d2f33;
}

.useful-faq dd {
  margin: 0 0 12px;
  color: #5a5b60;
}

@media (max-width: 1024px) {
  .useful-page {
    padding: 56px 0;
  }

  .useful-page__inner {
    padding: 0 20px;
  }

  .useful-memo__grid {
    grid-template-columns: 1fr;
  }

  .useful-table {
    min-width: 860px;
  }

  .useful-table-wrap {
    overflow-x: auto;
  }
}

@media (max-width: 768px) {
  .useful-page {
    padding: 44px 0;
  }

  .useful-page__inner {
    padding: 0 14px;
  }

  .useful-page__head,
  .useful-page__head p {
    text-align: center;
  }

  .useful-page__head p {
    margin-inline: auto;
  }

  .useful-toc__list {
    flex-direction: column;
    gap: 8px;
  }

  .useful-table-wrap {
    border: 0;
    box-shadow: none;
    background: transparent;
  }

  .useful-table thead {
    display: none;
  }

  .useful-table tbody,
  .useful-table tr,
  .useful-table td {
    display: block;
    width: 100%;
  }

  .useful-table tr {
    margin-bottom: 12px;
    border: 1px solid rgba(172, 173, 177, 0.2);
    border-left: 4px solid #bb0100;
    border-radius: 4px;
    background: #fff;
    box-shadow: 0 8px 20px rgba(45, 47, 51, 0.06);
  }

  .useful-table td {
    padding: 10px 12px;
    border: 0;
    font-size: 0.9rem;
  }

  .useful-table td::before {
    content: attr(data-label);
    display: block;
    margin-bottom: 4px;
    font-size: 0.62rem;
    font-weight: 800;
    text-transform: uppercase;
    color: #5a5b60;
  }
}