.section--useful {
  position: relative;
  overflow: hidden;
  background: #f7f8f5;
}

.useful-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 2rem;
}

.useful-head .section__header { margin-bottom: 0; }
.useful-head .section__desc { margin-inline: 0; }

.useful-controls {
  display: flex;
  gap: 0.6rem;
  padding-bottom: 0.25rem;
}

.useful-controls button {
  width: 48px;
  height: 48px;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
  font-size: 1rem;
  transition: transform var(--transition), border-color var(--transition);
}

.useful-controls button:hover {
  transform: translateY(-3px);
  border-color: var(--color-accent);
}

.useful-carousel {
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 26px;
  background: var(--color-surface);
  box-shadow: 0 24px 70px rgba(21, 24, 22, 0.07);
  touch-action: pan-y;
}

.useful-track {
  display: flex;
  align-items: stretch;
  transition: transform 0.65s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.useful-post {
  flex: 0 0 100%;
  display: grid;
  grid-template-columns: minmax(280px, 0.85fr) minmax(0, 1.15fr);
  align-items: start;
}

.useful-post__media {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
  background: #eef1ec;
}

.useful-post__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: contain;
}

.useful-post__content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: clamp(1.5rem, 4vw, 3rem);
}

.useful-post__category {
  margin-bottom: 1rem;
  padding: 0.45rem 0.75rem;
  border-radius: 999px;
  background: var(--color-bg-alt);
  color: var(--color-accent);
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.useful-post h3 {
  max-width: 620px;
  margin-bottom: 0.9rem;
  font-size: clamp(1.55rem, 3vw, 2.6rem);
  line-height: 1.12;
}

.useful-post__lead {
  max-width: 650px;
  margin-bottom: 1rem;
  color: var(--color-text);
  font-size: 0.98rem;
  font-weight: 600;
  line-height: 1.7;
}

.useful-post__body {
  position: relative;
  width: 100%;
  max-width: 680px;
  max-height: 8.5rem;
  overflow: hidden;
  transition: max-height 0.35s ease;
}

.useful-post__body::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3.5rem;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0), #fff 85%);
  pointer-events: none;
}

.useful-post.is-expanded .useful-post__body {
  max-height: 2000px;
}

.useful-post.is-expanded .useful-post__body::after {
  display: none;
}

.useful-post__text {
  display: grid;
  gap: 0.85rem;
}

.useful-post__text p,
.useful-post__list li {
  color: var(--color-text-muted);
  font-size: 0.88rem;
  line-height: 1.7;
}

.useful-post__quote {
  margin: 1rem 0 0;
  padding-left: 1rem;
  border-left: 2px solid var(--color-accent-light);
  color: var(--color-text);
  font-size: 0.92rem;
  font-style: italic;
  line-height: 1.6;
}

.useful-post__list {
  display: grid;
  gap: 0.45rem;
  margin: 0 0 1rem;
  padding: 0;
}

.useful-post__list li {
  position: relative;
  padding-left: 1.15rem;
  list-style: none;
}

.useful-post__list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--color-accent);
  font-weight: 700;
}

.useful-post__label {
  margin: 0 0 0.55rem;
  color: var(--color-text);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.useful-post__list--check li::before {
  content: "✓";
  font-size: 0.78rem;
}

.useful-post__toggle {
  margin-top: 1rem;
  padding: 0;
  border: 0;
  background: none;
  color: var(--color-accent);
  font: inherit;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
}

.useful-post__toggle:hover {
  opacity: 0.72;
}