.hb-mertra-guide {
  --ink: #151515;
  --copy: #353535;
  --muted: #707070;
  --line: #dedede;
  --soft: #f6f6f6;
  --white: #ffffff;
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0;
  color: var(--copy);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 17px;
  line-height: 1.78;
  overflow-wrap: break-word;
}

.hb-mertra-guide,
.hb-mertra-guide * {
  box-sizing: border-box;
}

.hb-mertra-guide > * {
  max-width: 100%;
}

.hb-mertra-guide p {
  margin: 0 0 22px;
}

.hb-mertra-guide h2 {
  width: 100%;
  margin: 66px 0 24px;
  padding-top: 19px;
  border-top: 2px solid var(--ink);
  color: var(--ink);
  font-size: clamp(27px, 3vw, 35px);
  font-weight: 750;
  line-height: 1.23;
  letter-spacing: -.025em;
  scroll-margin-top: 28px;
}

.hb-mertra-guide h3 {
  margin: 27px 0 12px;
  color: var(--ink);
  font-size: 21px;
  line-height: 1.35;
}

.hb-mertra-guide a:not(.hb-photo-link):not(.hb-btn) {
  color: var(--ink);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: #888888;
  text-underline-offset: 4px;
}

.hb-mertra-guide a:hover {
  text-decoration-color: var(--ink);
}

.hb-mertra-guide .hb-intro {
  width: 100%;
  margin-bottom: 31px;
  color: #252525;
  font-size: 20px;
  line-height: 1.7;
}

/* TABLE OF CONTENTS */
.hb-mertra-guide .hb-toc {
  display: flex;
  flex-wrap: nowrap;
  gap: 8px;
  width: 100%;
  margin: 31px 0 47px;
  padding: 12px;
  border: 1px solid var(--line);
  background: var(--soft);
}

.hb-mertra-guide .hb-toc a {
  flex: 1 1 0;
  min-width: 0;
  padding: 12px 9px;
  border: 1px solid #d0d0d0;
  background: var(--white);
  color: var(--ink);
  font-size: 13px;
  font-weight: 700;
  line-height: 1.35;
  text-align: center;
  text-decoration: none;
}

.hb-mertra-guide .hb-toc a:hover {
  background: var(--ink);
  color: var(--white);
  border-color: var(--ink);
}

/* EDITORIAL NOTE */
.hb-mertra-guide .hb-note {
  width: 100%;
  margin: 28px 0 34px;
  padding: 21px 25px;
  border-left: 4px solid var(--ink);
  background: var(--soft);
}

.hb-mertra-guide .hb-note strong {
  display: block;
  margin-bottom: 7px;
  color: var(--ink);
}

.hb-mertra-guide .hb-note p {
  margin: 0;
}

/* COMPARISON */
.hb-mertra-guide .hb-contrast {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  width: 100%;
  margin: 29px 0 34px;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--line);
}

.hb-mertra-guide .hb-contrast > div {
  min-width: 0;
  padding: 23px 25px;
}

.hb-mertra-guide .hb-contrast > div + div {
  border-left: 1px solid var(--line);
}

.hb-mertra-guide .hb-contrast strong {
  display: block;
  margin-bottom: 9px;
  color: var(--ink);
}

.hb-mertra-guide .hb-contrast p {
  margin: 0;
  color: #555555;
  font-size: 15px;
  line-height: 1.7;
}

/* ALL ARTICLE IMAGES — UNIFIED WIDTH */
.hb-mertra-guide .hb-photo {
  display: block;
  width: 100%;
  max-width: 100%;
  margin: 32px 0 37px;
  padding: 0;
}

.hb-mertra-guide .hb-photo-link {
  display: block;
  width: 100%;
  max-width: 100%;
  overflow: hidden;
  background: #f2f2f2;
  text-decoration: none;
}

.hb-mertra-guide .hb-photo-link img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  margin: 0;
  padding: 0;
  object-fit: contain;
}

.hb-mertra-guide figcaption {
  width: 100%;
  max-width: 100%;
  margin: 0;
  padding: 14px 18px;
  border: 1px solid var(--line);
  border-top: 0;
  background: #fafafa;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
  text-align: left;
}

/* INTEGRATED PRODUCT SECTION */
.hb-mertra-guide .hb-product {
  display: block;
  width: 100%;
  max-width: 100%;
  margin: 34px 0 38px;
  border: 1px solid var(--line);
  background: var(--white);
}

.hb-mertra-guide .hb-product-photo {
  display: block;
  width: 100%;
  max-width: 100%;
  padding: 0;
  background: #f4f4f4;
}

.hb-mertra-guide .hb-product-photo img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  margin: 0;
  padding: 0;
  object-fit: contain;
}

.hb-mertra-guide .hb-product-content {
  width: 100%;
  max-width: 100%;
  padding: 28px 31px 32px;
}

.hb-mertra-guide .hb-product-label {
  margin-bottom: 9px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .09em;
  text-transform: uppercase;
}

.hb-mertra-guide .hb-product-content h3 {
  margin: 0 0 15px;
  font-size: 25px;
}

.hb-mertra-guide .hb-product-content p {
  max-width: 100%;
  font-size: 16px;
}

.hb-mertra-guide .hb-btn {
  display: inline-block;
  max-width: 100%;
  padding: 13px 23px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--white);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.45;
  text-align: center;
  text-decoration: none;
}

.hb-mertra-guide .hb-btn:hover {
  background: var(--white);
  color: var(--ink);
}

/* FABRIC OBSERVATIONS */
.hb-mertra-guide .hb-read {
  width: 100%;
  margin: 29px 0 35px;
  border-top: 1px solid var(--line);
}

.hb-mertra-guide .hb-read-row {
  display: grid;
  grid-template-columns: 160px minmax(0, 1fr);
  gap: 26px;
  padding: 21px 0;
  border-bottom: 1px solid var(--line);
}

.hb-mertra-guide .hb-read-row strong {
  color: var(--ink);
}

.hb-mertra-guide .hb-read-row p {
  margin: 0;
  font-size: 16px;
}

/* FAQ */
.hb-mertra-guide .hb-faq {
  width: 100%;
  max-width: 100%;
}

.hb-mertra-guide .hb-faq details {
  width: 100%;
  margin-bottom: 11px;
  border: 1px solid var(--line);
  background: var(--white);
}

.hb-mertra-guide .hb-faq summary {
  padding: 19px 22px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  cursor: pointer;
}

.hb-mertra-guide .hb-faq details[open] summary {
  border-bottom: 1px solid var(--line);
}

.hb-mertra-guide .hb-answer {
  padding: 19px 22px 23px;
}

.hb-mertra-guide .hb-answer p {
  margin: 0;
  font-size: 16px;
}

/* FINAL CTA */
.hb-mertra-guide .hb-closing {
  width: 100%;
  max-width: 100%;
  margin: 63px 0 0;
  padding: clamp(28px, 4vw, 46px);
  border: 2px solid var(--ink);
  background: var(--soft);
}

.hb-mertra-guide .hb-closing-title {
  margin-bottom: 17px;
  color: var(--ink);
  font-size: clamp(25px, 3vw, 32px);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -.02em;
}

.hb-mertra-guide .hb-closing p {
  max-width: 100%;
}

.hb-mertra-guide .hb-closing .hb-btn {
  margin-top: 8px;
}

/* RESPONSIVE */
@media (max-width: 760px) {
  .hb-mertra-guide {
    font-size: 16px;
    line-height: 1.72;
  }

  .hb-mertra-guide .hb-intro {
    font-size: 18px;
  }

  .hb-mertra-guide h2 {
    margin-top: 52px;
    font-size: 27px;
  }

  .hb-mertra-guide .hb-contrast {
    grid-template-columns: 1fr;
  }

  .hb-mertra-guide .hb-contrast > div + div {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .hb-mertra-guide .hb-read-row {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .hb-mertra-guide .hb-product-content {
    padding: 23px 21px 28px;
  }

  .hb-mertra-guide .hb-photo,
  .hb-mertra-guide .hb-product,
  .hb-mertra-guide .hb-photo-link {
    width: 100%;
    max-width: 100%;
  }

  .hb-mertra-guide .hb-product-photo {
    padding: 0;
  }
}

@media (max-width: 480px) {
  .hb-mertra-guide .hb-toc {
    overflow-x: auto;
  }

  .hb-mertra-guide .hb-toc a {
    flex: 0 0 auto;
    font-size: 12px;
  }

  .hb-mertra-guide .hb-btn {
    display: block;
    width: 100%;
  }

  .hb-mertra-guide .hb-note {
    padding: 19px;
  }

  .hb-mertra-guide figcaption {
    padding: 12px 14px;
    font-size: 13px;
  }
}