:root {
  /* Brand colors */
  --color-navy-900: #001442;   /* topbar background */
  --color-navy-950: #001442;   /* footer background */
  --color-navy-800: #001442;   /* active language pill */
  --color-red-600:  #e20209;    /* primary accent / CTA */
  --color-red-700:  #e20209;    /* CTA hover */
  --color-red-500:  #e20209;    /* active nav link / hover link */
  --color-red-400:  #df7d8d;    /* footer link hover */

  --color-text-body:       oklch(25% 0.02 260);
  --color-text-nav:        oklch(30% 0.03 260);
  --color-text-topbar:     oklch(85% 0.02 260);
  --color-text-footer:     oklch(80% 0.02 260);
  --color-text-footer-mut: oklch(72% 0.02 260);
  --color-text-footer-sub: oklch(65% 0.02 260);

  --color-border-header: oklch(90% 0.01 260);
  --color-border-footer: oklch(100% 0 0 / 0.13);
  --color-white: #ffffff;

  --font-base: 'Roboto', -apple-system, BlinkMacSystemFont, Arial, sans-serif;

  --container-max: 1400px;
  --radius-sm: 7px;
  --radius-md: 8px;
  --radius-lg: 11px;

  --transition-fast: 0.18s ease;

  
    --paper: #f6f5f2;
    --line: oklch(88% 0.01 260);

}

.text-red{
    color: #e20209;
}


  /* ================= blog-HERO BANNER ================= */
  .blog-hero {
    position: relative;
    background: var(--color-navy-900);
    overflow: hidden;
    padding: 0;
  }
  .blog-hero-grid {
    max-width: var(--container-max);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    align-items: stretch;
    min-height: 100%;
  }
  .blog-hero-copy {
    padding: 96px 56px 88px 56px;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }
  .blog-hero-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--color-red-400);
    font-size: 13.5px;
    letter-spacing: 0.02em;
    margin-bottom: 22px;
    font-weight: 500;
  }
  .blog-hero-eyebrow::before {
    content: "";
    width: 26px;
    height: 1.5px;
    background: var(--color-red-600);
    display: inline-block;
  }
  .blog-hero-copy h1 {
    color: var(--color-white);
    font-size: clamp(32px, 3.6vw, 48px);
    line-height: 1.12;
    font-weight: 600;
    margin: 0 0 22px 0;
    letter-spacing: -0.01em;
  }
  .blog-hero-copy p {
    color: var(--color-text-topbar);
    font-size: 17px;
    line-height: 1.6;
    margin: 0 0 30px 0;
  }
  .blog-hero-meta {
    display: flex;
    align-items: center;
    gap: 22px;
    color: var(--color-text-footer-sub);
    font-size: 13.5px;
  }
  .blog-hero-meta span:not(:last-child) {
    position: relative;
    padding-right: 22px;
  }
  .blog-hero-meta span:not(:last-child)::after {
    content: "";
    position: absolute;
    right: 0; top: 50%;
    transform: translateY(-50%);
    width: 3px; height: 3px;
    border-radius: 50%;
    background: var(--color-text-footer-sub);
  }
  .blog-hero-visual {
    position: relative;
    background:
      radial-gradient(circle at 30% 20%, rgba(226,2,9,0.16), transparent 55%),
      linear-gradient(160deg, #001a56 0%, #000d33 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    border-left: 1px solid rgba(255,255,255,0.08);
  }
  .size-diagram {
    width: 100%;
    height: 100%;
    padding: 56px 48px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 14px;
  }
  .size-bar-row {
    display: grid;
    grid-template-columns: 78px 1fr;
    align-items: center;
    gap: 14px;
  }
  .size-bar-label {
    color: rgba(255,255,255,0.65);
    font-size: 12.5px;
    text-align: right;
    letter-spacing: 0.01em;
  }
  .size-bar-track {
    height: 9px;
    background: rgba(255,255,255,0.08);
    border-radius: 5px;
    overflow: hidden;
  }
  .size-bar-fill {
    height: 100%;
    border-radius: 5px;
    background: linear-gradient(90deg, var(--color-red-600), #ff5b5f);
  }

  /* ================= LAYOUT ================= */
  .content-section {
    background: var(--color-white);
    padding: 40px 0 40px 0;
  }

  .wrap{
    max-width: 1100px;
    margin:  0 auto;
  }
  
  .layout {
    display: grid;
    grid-template-columns: auto;
    gap: 72px;
    align-items: start;
  }
  .toc {
    position: sticky;
    top: 132px;
    border-left: 2px solid var(--line);
    padding-left: 22px;
  }
  .toc-title {
    font-size: 12.5px;
    font-weight: 600;
    color: var(--color-navy-900);
    margin: 0 0 16px 0;
    letter-spacing: 0.01em;
  }
  .toc ol {
    list-style: none;
    margin: 0; padding: 0;
    counter-reset: toc;
  }
  .toc li {
    counter-increment: toc;
    margin-bottom: 13px;
    font-size: 14px;
    line-height: 1.4;
  }
  .toc li a {
    color: var(--color-text-nav);
    transition: color var(--transition-fast);
  }
  .toc li a:hover { color: var(--color-red-600); }
  .toc li::before {
    content: counter(toc, decimal-leading-zero);
    color: var(--color-red-600);
    font-weight: 600;
    font-size: 12.5px;
    margin-right: 9px;
  }

  article { max-width: 1-20px;margin: 0 auto; }
  article img{ margin: 0 auto 20px; }
  article > p.lede {
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text-nav);
    margin: 0 0 40px 0;
  }
  article h1 {
    margin-bottom: 20px;
  }
  article h2 {
    font-size: 25px;
    font-weight: 600;
    color: var(--color-navy-900);
    margin: 46px 0 18px 0;
    line-height: 1.3;
    scroll-margin-top: 32px;
  }
  article h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-navy-900);
    margin: 30px 0 12px 0;
  }
  article p {
    font-size: 16px;
    line-height: 1.75;
    color: var(--color-text-body);
    margin: 0 0 18px 0;
  }
  article ul, article ol.plain {
    margin: 0 0 20px 0;
    padding-left: 20px;
  }
  article ul li, article ol.plain li {
    font-size: 16px;
    line-height: 1.7;
    margin-bottom: 8px;
    list-style: auto;
  }
  .callout {
    border-left: 3px solid var(--color-red-600);
    background: var(--paper);
    padding: 18px 22px;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    margin: 26px 0;
    font-size: 15px;
    line-height: 1.65;
    color: var(--color-text-nav);
  }
  .callout strong { color: var(--color-navy-900); }

  /* size cards */
  .size-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    margin: 22px 0 30px 0;
  }
  .size-card {
    border: 1px solid var(--color-border-header);
    border-radius: var(--radius-md);
    padding: 18px 16px;
    background: var(--color-white);
  }
  .size-card.active {
    border-color: var(--color-navy-900);
    background: var(--color-navy-900);
  }
  .size-card-name {
    font-size: 13.5px;
    font-weight: 600;
    color: var(--color-navy-900);
    margin-bottom: 10px;
  }
  .size-card.active .size-card-name { color: var(--color-white); }
  .size-card-row {
    display: flex;
    justify-content: space-between;
    font-size: 12.5px;
    color: var(--color-text-nav);
    padding: 6px 0;
    border-top: 1px solid var(--line);
  }
  .size-card-row:first-of-type { border-top: none; }
  .size-card.active .size-card-row {
    color: var(--color-text-topbar);
    border-top-color: rgba(255,255,255,0.12);
  }
  .size-card-row span:last-child { font-weight: 600; color: var(--color-text-body); text-align: right; }
  .size-card.active .size-card-row span:last-child { color: var(--color-white); }

  /* responsive table */
  .table-wrap {
    overflow-x: auto;
    margin: 22px 0 30px 0;
    border: 1px solid var(--color-border-header);
    border-radius: var(--radius-md);
  }
  table.classify {
    width: 100%;
    border-collapse: collapse;
    font-size: 14.5px;
    min-width: 560px;
  }
  table.classify thead th {
    background: var(--color-navy-900);
    color: var(--color-white);
    text-align: left;
    padding: 14px 18px;
    font-weight: 600;
  }
  table.classify tbody td {
    padding: 13px 18px;
    border-top: 1px solid var(--line);
    color: var(--color-text-body);
  }
  table.classify tbody tr:nth-child(odd) { background: var(--paper); }
  table.classify tbody td:first-child { font-weight: 600; color: var(--color-navy-900); }

  /* numbered process (mistakes) */
  .mistake-list {
    counter-reset: mistake;
    display: flex;
    flex-direction: column;
    gap: 0;
    margin: 22px 0 30px 0;
  }
  .mistake {
    counter-increment: mistake;
    padding: 20px 0;
    border-top: 1px solid var(--line);
  }
  .mistake:last-child { border-bottom: 1px solid var(--line); }
  .mistake::before {
    content: counter(mistake, decimal-leading-zero);
    font-size: 15px;
    font-weight: 700;
    color: var(--color-red-600);
  }
  .mistake h4 {
    margin: 0 0 6px 0;
    font-size: 16px;
    font-weight: 600;
    color: var(--color-navy-900);
  }
  .mistake p { margin: 0; font-size: 15px; line-height: 1.65; color: var(--color-text-nav); }

  /* FAQ */
  .faq { margin-top: 8px; }
  .faq-item {
    border-bottom: 1px solid var(--line);
  }
  .faq-item summary {
    list-style: none;
    cursor: pointer;
    padding: 20px 0;
    font-size: 16px;
    font-weight: 600;
    color: var(--color-navy-900);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
  }
  .faq-item summary::-webkit-details-marker { display: none; }
  .faq-item summary::after {
    content: "+";
    flex: none;
    font-size: 20px;
    font-weight: 400;
    color: var(--color-red-600);
    transition: transform var(--transition-fast);
  }
  .faq-item[open] summary::after { transform: rotate(45deg); }
  .faq-item p {
    margin: 0 0 22px 0;
    font-size: 15px;
    line-height: 1.7;
    color: var(--color-text-nav);
    max-width: 62ch;
  }

  /* CTA band */
  .cta-band {
    margin-top: 24px;
    background: var(--color-navy-900);
    border-radius: var(--radius-lg);
    padding: 44px 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    flex-wrap: wrap;
  }
  .cta-band h3 {
    color: var(--color-white);
    font-size: 21px;
    margin: 0 0 8px 0;
  }
  .cta-band p {
    color: var(--color-text-topbar);
    margin: 0;
    font-size: 15px;
    /* max-width: 44ch; */
  }
  .cta-btn {
    background: var(--color-red-600);
    color: var(--color-white);
    padding: 13px 26px;
    border-radius: var(--radius-sm);
    font-size: 14.5px;
    font-weight: 600;
    white-space: nowrap;
    transition: background var(--transition-fast);
  }
  .cta-btn:hover { background: var(--color-red-700); }


  @media (max-width: 980px) {
    .blog-hero-grid { grid-template-columns: 1fr; }
    .blog-hero-visual { min-height: 260px; }
    .blog-hero-copy { padding: 64px 32px 48px 32px; }
    .layout { grid-template-columns: 100%; gap:20px}
    .toc { position: static; border-left: none; padding-left: 0; border-top: 2px solid var(--line); padding-top: 18px; }
    .wrap { padding: 0 24px; }
    .size-cards { grid-template-columns: repeat(2, 1fr); }
    .cta-band { flex-direction: column; align-items: flex-start; }
    article h2{
        margin: 26px 0 12px 0;
    }
  }