:root {
    --sun: #FFB800;
    --green: #1DB954;
    --sky: #0A1628;
    --sky-mid: #112240;
    --sky-light: #1A3458;
    --white: #F5F9FF;
    --muted: #8BA3C4;
    --accent: #00D4FF;
    --card-bg: rgba(17,34,64,0.85);
    --radius: 16px;
  }

  :root {
    --sun: #FFB800;
    --green: #1DB954;
    --sky: #0A1628;
    --sky-mid: #112240;
    --sky-light: #1A3458;
    --white: #F5F9FF;
    --muted: #8BA3C4;
    --accent: #00D4FF;
    --card-bg: rgba(17,34,64,0.85);
    --radius: 16px;
  }

  * { margin: 0; padding: 0; box-sizing: border-box; }

  body {
    font-family: 'DM Sans', sans-serif;
    background: var(--sky);
    color: var(--white);
    overflow-x: hidden;
    line-height: 1.75;
  }

  .nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    display: flex; align-items: center; justify-content: space-between;
    padding: 16px 32px;
    background: rgba(10,22,40,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255,184,0,0.15);
  }

  .nav-logo {
    font-family: 'Syne', sans-serif; font-weight: 800; font-size: 1.3rem;
    color: var(--sun); display: flex; align-items: center; gap: 8px;
    text-decoration: none;
  }

  .nav-logo span { color: var(--white); }

  .nav-home {
    font-size: 0.85rem; color: var(--muted); text-decoration: none;
    border: 1px solid rgba(255,255,255,0.15); padding: 6px 16px;
    border-radius: 20px; transition: all 0.2s;
  }

  .nav-home:hover { color: var(--white); border-color: var(--sun); }

  .nav-left { display: flex; align-items: center; gap: 16px; position: relative; }

  .nav-burger {
    display: flex; flex-direction: column; justify-content: center; gap: 5px;
    width: 38px; height: 38px; background: none; border: 1px solid rgba(255,255,255,0.15);
    border-radius: 10px; cursor: pointer; padding: 0; transition: all 0.2s;
  }

  .nav-burger:hover, .nav-burger.active { border-color: var(--sun); }

  .burger-line {
    display: block; width: 18px; height: 2px; background: var(--white);
    margin: 0 auto; border-radius: 2px; transition: all 0.25s;
  }

  .nav-burger.active .burger-line:nth-child(1) { transform: translateY(7px) rotate(45deg); }

  .nav-burger.active .burger-line:nth-child(2) { opacity: 0; }

  .nav-burger.active .burger-line:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  .nav-guides-panel {
    display: none;
    position: absolute; top: calc(100% + 12px); left: 0;
    background: var(--sky-mid); border: 1px solid rgba(255,184,0,0.2);
    border-radius: 14px; padding: 22px; box-shadow: 0 20px 50px rgba(0,0,0,0.4);
    gap: 28px; width: max-content; max-width: 90vw;
  }

  .nav-guides-panel.open { display: flex; }

  .nav-guides-col { min-width: 190px; }

  .nav-guides-heading {
    font-family: 'Syne', sans-serif; font-weight: 700; font-size: 0.78rem;
    color: var(--sun); text-transform: uppercase; letter-spacing: 0.04em;
    margin-bottom: 10px;
  }

  .nav-guides-col a {
    display: block; color: var(--muted); text-decoration: none; font-size: 0.88rem;
    padding: 7px 0; transition: color 0.15s;
  }

  .nav-guides-col a:hover { color: var(--white); }

  .article-hero {
    padding: 120px 24px 56px;
    background:
      radial-gradient(ellipse 70% 50% at 50% 0%, rgba(255,184,0,0.12) 0%, transparent 60%),
      linear-gradient(180deg, #0D1F3C 0%, #0A1628 100%);
    text-align: center;
  }

  .breadcrumb {
    font-size: 0.8rem; color: var(--muted); margin-bottom: 16px;
    display: flex; align-items: center; justify-content: center; gap: 8px;
  }

  .breadcrumb a { color: var(--muted); text-decoration: none; transition: color 0.2s; }

  .breadcrumb a:hover { color: var(--sun); }

  .breadcrumb span { font-size: 0.7rem; opacity: 0.6; }

  .article-tag {
    display: inline-block; background: rgba(0,212,255,0.1);
    color: var(--accent); font-size: 0.8rem; font-weight: 600;
    padding: 6px 16px; border-radius: 20px; margin-bottom: 20px;
    border: 1px solid rgba(0,212,255,0.2);
    letter-spacing: 0.05em; text-transform: uppercase;
  }

  .article-hero h1 {
    font-family: 'Syne', sans-serif; font-weight: 800; font-size: 2.8rem;
    line-height: 1.15; max-width: 800px; margin: 0 auto 24px;
    letter-spacing: -0.02em;
  }

  .article-hero h1 em { font-style: normal; color: var(--sun); }

  .article-meta {
    display: flex; align-items: center; justify-content: center; gap: 24px;
    color: var(--muted); font-size: 0.88rem; margin-bottom: 24px;
  }

  .meta-item { display: flex; align-items: center; gap: 6px; }

  .update-badge {
    display: inline-flex; align-items: center; gap: 8px;
    background: rgba(29,185,84,0.1);
    border: 1px solid rgba(29,185,84,0.3);
    color: var(--green);
    font-size: 0.82rem; font-weight: 500;
    padding: 8px 18px; border-radius: 10px;
    margin-top: 8px;
  }

  .article-wrap {
    max-width: 1100px; margin: 0 auto;
    padding: 56px 24px 80px;
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 48px;
    align-items: start;
  }

  .article-body h2 {
    font-family: 'Syne', sans-serif;
    font-size: 1.6rem; font-weight: 800;
    margin: 48px 0 18px;
    padding-top: 48px;
    border-top: 1px solid rgba(255,255,255,0.07);
    line-height: 1.3;
  }

  .article-body h2:first-of-type { border-top: none; margin-top: 0; padding-top: 0; }

  .article-body h3 {
    font-family: 'Syne', sans-serif;
    font-size: 1.25rem; font-weight: 700;
    margin: 28px 0 12px; color: var(--sun);
  }

  .article-body p {
    font-size: 1.05rem; color: #B8CFEA; margin-bottom: 20px;
    line-height: 1.8; font-weight: 300;
  }

  .article-body strong { color: var(--white); font-weight: 500; }

  .article-body a { color: var(--accent); text-decoration: none; }

  .article-body a:hover { text-decoration: underline; }

  .article-body ul, .article-body ol {
    margin-bottom: 24px; padding-left: 24px;
    color: #B8CFEA;
  }

  .callout {
    display: flex; gap: 16px; padding: 20px;
    border-radius: var(--radius); margin: 32px 0;
  }

  .callout-icon { font-size: 1.4rem; line-height: 1; }

  .callout-body { flex: 1; }

  .callout-title { font-family: 'Syne', sans-serif; font-weight: 700; font-size: 0.95rem; margin-bottom: 6px; }

  .callout-text { font-size: 0.88rem; color: var(--muted); margin-bottom: 0 !important; line-height: 1.5 !important; }

  .callout-news {
    background: rgba(0,212,255,0.06);
    border: 1px solid rgba(0,212,255,0.2);
  }

  .callout-news .callout-title { color: var(--accent); }

  .callout-warning { background: rgba(255,184,0,0.08); border: 1px solid rgba(255,184,0,0.25); }

  .callout-warning .callout-title { color: var(--sun); }

  .callout-success {
    background: rgba(29,185,84,0.06);
    border: 1px solid rgba(29,185,84,0.2);
  }

  .callout-success .callout-title { color: var(--green); }

  .step-list { margin: 28px 0; position: relative; padding-left: 28px; }

  .step-list::before {
    content: '';
    position: absolute; left: 8px; top: 8px; bottom: 8px;
    width: 2px; background: rgba(255,184,0,0.2);
  }

  .step-item { position: relative; margin-bottom: 28px; }

  .step-item::before {
    content: attr(data-step);
    position: absolute; left: -34px; top: -2px;
    width: 24px; height: 24px; border-radius: 50%;
    background: var(--sun); color: var(--sky);
    font-family: 'Syne', sans-serif; font-weight: 800; font-size: 0.78rem;
    display: flex; align-items: center; justify-content: center;
    box-shadow: 0 0 0 4px var(--sky);
  }

  .step-title { font-weight: 700; font-size: 1.05rem; margin-bottom: 6px; font-family: 'Syne', sans-serif; }

  .step-desc { font-size: 0.95rem; color: #B8CFEA; line-height: 1.7; }

  .compare-table-outer { margin: 32px 0; border-radius: var(--radius); overflow: hidden; border: 1px solid rgba(255,255,255,0.08); }

  .compare-table { width: 100%; border-collapse: collapse; text-align: left; background: var(--card-bg); font-size: 0.9rem; }

  .compare-table th { background: rgba(255,255,255,0.03); padding: 14px 18px; font-weight: 600; color: var(--sun); font-family: 'Syne', sans-serif; text-transform: uppercase; font-size: 0.75rem; letter-spacing: 0.05em; border-bottom: 2px solid rgba(255,184,0,0.15); }

  .compare-table td { padding: 14px 18px; border-bottom: 1px solid rgba(255,255,255,0.05); color: #B8CFEA; }

  .compare-table tr:hover td { background: rgba(255,255,255,0.03); }

  .compare-table tr:last-child td { border-bottom: none; }

  .td-green { color: var(--green); font-weight: 500; }

  .td-amber { color: var(--sun); font-weight: 500; }

  .product-cta {
    background: var(--card-bg);
    border: 1px solid rgba(255,184,0,0.25);
    border-radius: var(--radius); padding: 24px;
    margin: 36px 0;
  }

  .product-cta-label {
    font-size: 0.72rem; font-weight: 600; letter-spacing: 0.1em;
    text-transform: uppercase; color: var(--sun); margin-bottom: 10px;
  }

  .product-cta h3 {
    font-family: 'Syne', sans-serif; font-weight: 700;
    font-size: 1.1rem; margin-bottom: 8px; margin-top: 0;
  }

  .product-cta p {
    font-size: 0.88rem; color: var(--muted);
    margin-bottom: 14px; line-height: 1.6;
  }

  a.btn-amazon, .article-body a.btn-amazon, .btn-amazon {
    display: inline-flex; align-items: center; gap: 10px;
    background: linear-gradient(135deg, #FF9900, #FFB800);
    color: #0A1628 !important;
    border: none;
    font-family: 'DM Sans', sans-serif; font-weight: 700;
    font-size: 1rem; padding: 14px 28px; border-radius: 50px;
    text-decoration: none !important; transition: all 0.25s;
    box-shadow: 0 4px 20px rgba(255,153,0,0.35);
    cursor: pointer;
  }

  a.btn-amazon:hover, .article-body a.btn-amazon:hover, .btn-amazon:hover {
    background: linear-gradient(135deg, #FFB800, #FFCC33);
    transform: translateY(-2px);
    text-decoration: none !important;
    box-shadow: 0 8px 30px rgba(255,153,0,0.45);
    color: #0A1628 !important;
  }

  .amazon-logo { font-weight: 800; font-style: italic; color: #0A1628 !important; }

  .product-cta-price { font-size: 1.3rem; font-weight: 800; color: var(--green); margin-bottom: 10px; font-family: 'Syne', sans-serif; }

  .product-cta-savings { display: inline-block; background: rgba(29,185,84,0.15); color: var(--green); font-size: 0.78rem; font-weight: 600; padding: 4px 12px; border-radius: 20px; margin-bottom: 12px; }

  .sidebar { position: sticky; top: 90px; }

  .sidebar-card {
    background: var(--card-bg);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius); padding: 24px;
    margin-bottom: 20px;
  }

  .sidebar-title {
    font-family: 'Syne', sans-serif; font-size: 0.9rem;
    font-weight: 700; margin-bottom: 16px;
    padding-bottom: 12px; border-bottom: 1px solid rgba(255,255,255,0.07);
    color: var(--sun);
  }

  .toc-list { list-style: none; }

  .toc-list li { margin-bottom: 8px; }

  .toc-list a {
    font-size: 0.87rem; color: var(--muted); text-decoration: none;
    display: flex; align-items: flex-start; gap: 8px;
    line-height: 1.4; transition: color 0.2s;
  }

  .toc-list a:hover { color: var(--white); }

  .toc-num { color: var(--sun); font-size: 0.75rem; font-weight: 600; flex-shrink: 0; margin-top: 2px; }

  .sidebar-product {
    display: flex; gap: 12px; align-items: flex-start;
    padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,0.05);
  }

  .sidebar-product:last-of-type { border-bottom: none; }

  .sidebar-product-icon {
    width: 44px; height: 44px; border-radius: 10px;
    background: rgba(255,184,0,0.1); display: flex;
    align-items: center; justify-content: center;
    font-size: 1.2rem; flex-shrink: 0;
  }

  .sidebar-product-name { font-size: 0.85rem; font-weight: 600; margin-bottom: 3px; }

  .sidebar-product-desc { font-size: 0.78rem; color: var(--muted); line-height: 1.4; }

  .sidebar-product a {
    font-size: 0.78rem; color: var(--accent);
    text-decoration: none; font-weight: 500;
  }

  .sidebar-product a:hover { text-decoration: underline; }

  .status-pill {
    display: inline-flex; align-items: center; gap: 6px;
    font-size: 0.8rem; font-weight: 600;
    padding: 5px 12px; border-radius: 20px; margin-bottom: 8px;
  }

  .status-amber { background: rgba(255,184,0,0.15); color: var(--sun); border: 1px solid rgba(255,184,0,0.3); }

  .status-green { background: rgba(29,185,84,0.15); color: var(--green); border: 1px solid rgba(29,185,84,0.3); }

  .status-dot { width: 7px; height: 7px; border-radius: 50%; background: currentColor; animation: blink 1.5s ease-in-out infinite; }

  @keyframes blink { 0%,100% { opacity: 1; }

  50% { opacity: 0.3; }

  }

  .sidebar-stat { display: flex; justify-content: space-between; align-items: center; padding: 8px 0; border-bottom: 1px solid rgba(255,255,255,0.05); font-size: 0.85rem; }

  .sidebar-stat:last-child { border-bottom: none; }

  .sidebar-stat-label { color: var(--muted); }

  .sidebar-stat-val { font-weight: 600; color: var(--white); }

  .disclaimer {
    background: rgba(255,255,255,0.03);
    border-top: 1px solid rgba(255,255,255,0.07);
    padding: 28px 24px; text-align: center;
    font-size: 0.8rem; color: var(--muted); line-height: 1.7;
    max-width: 900px; margin: 0 auto;
  }

  .disclaimer strong { color: rgba(255,255,255,0.4); }

  footer {
    background: #060F1E; padding: 36px 24px;
    text-align: center; border-top: 1px solid rgba(255,255,255,0.06);
  }

  footer .logo {
    font-family: 'Syne', sans-serif; font-size: 1.3rem;
    font-weight: 800; color: var(--sun); display: block; margin-bottom: 10px;
  }

  footer p { color: var(--muted); font-size: 0.85rem; }

  footer a { color: var(--accent); text-decoration: none; }

  footer a:hover { text-decoration: underline; }

  .article-date {
    text-align: center; color: var(--muted); font-size: 0.85rem; margin: 0 0 12px;
  }

  .last-updated {
    text-align: left; color: var(--muted); font-size: 0.85rem; margin: 32px 0 0;
    font-style: italic;
  }

  .article-body li { margin-bottom: 10px; font-size: 1.02rem; line-height: 1.7; }

  .callout-warn {
    background: rgba(255,184,0,0.06);
    border: 1px solid rgba(255,184,0,0.25);
  }

  .td-red { color: #FF6B6B; font-weight: 500; }

  .status-blue  { background: rgba(0,212,255,0.12);  color: var(--accent); border: 1px solid rgba(0,212,255,0.3); }

  .timeline { margin: 28px 0; position: relative; padding-left: 28px; }

  .timeline::before {
    content: '';
    position: absolute; left: 8px; top: 8px; bottom: 8px;
    width: 2px; background: rgba(255,184,0,0.2);
  }

  .timeline-item { position: relative; margin-bottom: 28px; }

  .timeline-item::before {
    content: '';
    position: absolute; left: -24px; top: 6px;
    width: 10px; height: 10px; border-radius: 50%;
    background: var(--sun); border: 2px solid var(--sky);
    box-shadow: 0 0 0 3px rgba(255,184,0,0.2);
  }

  .timeline-item.future::before { background: var(--sky-light); border-color: var(--muted); box-shadow: none; }

  .timeline-date {
    font-size: 0.78rem; font-weight: 600; letter-spacing: 0.08em;
    text-transform: uppercase; color: var(--sun); margin-bottom: 5px;
  }

  .timeline-item.future .timeline-date { color: var(--muted); }

  .timeline-title { font-weight: 600; font-size: 1rem; margin-bottom: 5px; }

  .timeline-desc { font-size: 0.9rem; color: var(--muted); line-height: 1.6; }

  .month-chart { margin: 28px 0; }

  .month-row {
    display: grid; grid-template-columns: 52px 1fr 80px;
    align-items: center; gap: 12px; margin-bottom: 10px;
    font-size: 0.88rem;
  }

  .month-label { color: var(--muted); font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; font-size: 0.78rem; }

  .month-bar-outer {
    height: 22px; background: rgba(255,255,255,0.05);
    border-radius: 6px; overflow: hidden; position: relative;
  }

  .month-bar-inner {
    height: 100%; border-radius: 6px;
    background: linear-gradient(90deg, var(--accent), var(--sun));
    transition: width 0.6s ease;
  }

  .month-bar-inner.winter { background: linear-gradient(90deg, #3a6d9c, var(--accent)); }

  .month-value { color: var(--white); font-weight: 600; text-align: right; font-variant-numeric: tabular-nums; }

  .month-value small { color: var(--muted); font-weight: 400; font-size: 0.78rem; }

  .related-link {
    display: block; padding: 10px 0;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    color: var(--muted); text-decoration: none;
    font-size: 0.86rem; transition: color 0.2s;
  }

  .related-link:last-child { border-bottom: none; }

  .related-link:hover { color: var(--accent); }

  .related-link strong { color: var(--white); display: block; margin-bottom: 2px; font-size: 0.9rem; font-weight: 600; }

  .versus-grid {
    display: grid; grid-template-columns: 1fr 1fr; gap: 18px;
    margin: 28px 0;
  }

  .versus-card {
    background: var(--card-bg);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius); padding: 22px;
  }

  .versus-card.plugin { border-color: rgba(0,212,255,0.3); }

  .versus-card.rooftop { border-color: rgba(255,184,0,0.3); }

  .versus-label {
    font-size: 0.72rem; font-weight: 600; letter-spacing: 0.1em;
    text-transform: uppercase; margin-bottom: 8px;
  }

  .versus-card.plugin .versus-label { color: var(--accent); }

  .versus-card.rooftop .versus-label { color: var(--sun); }

  .versus-card h4 {
    font-family: 'Syne', sans-serif; font-size: 1.05rem;
    font-weight: 700; margin-bottom: 14px;
  }

  .versus-list { list-style: none; }

  .versus-list li {
    font-size: 0.9rem; color: #B8CFEA;
    padding: 7px 0 7px 22px; position: relative;
    border-bottom: 1px solid rgba(255,255,255,0.04);
  }

  .versus-list li:last-child { border-bottom: none; }

  .versus-list li::before {
    content: '✓'; position: absolute; left: 0; top: 7px;
    color: var(--green); font-weight: 700;
  }

  .versus-list li.con::before { content: '✕'; color: #FF6B6B; }

  .cost-vis { margin: 28px 0; }

  .cost-row {
    display: grid; grid-template-columns: 130px 1fr 100px;
    gap: 14px; align-items: center; margin-bottom: 14px;
    font-size: 0.9rem;
  }

  .cost-row-label { color: var(--muted); }

  .cost-bar {
    height: 22px; border-radius: 6px;
    background: linear-gradient(90deg, var(--sun), #FFD566);
    box-shadow: 0 2px 8px rgba(255,184,0,0.15);
  }

  .cost-bar.plugin { background: linear-gradient(90deg, var(--accent), #66E6FF); }

  .cost-row-val { font-weight: 600; color: var(--white); text-align: right; }

  .decision-box {
    background: rgba(255,184,0,0.06);
    border: 1px solid rgba(255,184,0,0.2);
    border-radius: var(--radius); padding: 22px;
    margin: 24px 0;
  }

  .decision-box h4 {
    font-family: 'Syne', sans-serif; font-size: 1rem;
    font-weight: 700; margin-bottom: 10px; color: var(--sun);
  }

  .decision-box p { font-size: 0.93rem; color: #B8CFEA; margin: 0; }

  .sidebar-stat { display: flex; justify-content: space-between; align-items: center; padding: 8px 0; border-bottom: 1px solid rgba(255,255,255,0.05); font-size: 0.85rem; }

  .mono { font-family: 'IBM Plex Mono', monospace; }

  .diagram-panel {
    background: var(--card-bg); border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius); padding: 24px; margin: 24px 0;
  }

  .schematic { width: 100%; height: auto; overflow: visible; }

  .flow-line { stroke: rgba(255,184,0,0.35); stroke-width: 2; fill: none; }

  .node-box {
    fill: var(--sky-mid); stroke: rgba(255,255,255,0.15); stroke-width: 1.5;
    cursor: pointer; transition: all 0.2s;
  }

  .node-box:hover { stroke: var(--sun); }

  .node-box.active { fill: rgba(255,184,0,0.15); stroke: var(--sun); stroke-width: 2; }

  .node-label { fill: var(--white); font-family: 'DM Sans', sans-serif; font-size: 13px; font-weight: 600; pointer-events: none; }

  [data-node] { outline: none; }

  [data-node]:focus-visible .node-box { stroke: var(--accent); stroke-width: 2.5; }

  .diagram-hint { text-align: center; font-size: 0.82rem; color: var(--muted); margin-top: 14px; }

  .node-detail { display: none; margin-top: 20px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,0.08); }

  .node-detail.visible { display: block; }

  .node-detail h3 { color: var(--sun); margin-top: 0; }

  .node-detail p { color: #B8CFEA; margin-bottom: 0; font-size: 0.95rem; }

  .calc-box {
    background: var(--card-bg); border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius); padding: 24px; margin: 24px 0;
  }

  .calc-row {
    display: flex; align-items: center; justify-content: space-between;
    padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,0.05);
    gap: 12px; flex-wrap: wrap;
  }

  .calc-row:last-of-type { border-bottom: none; }

  .calc-row label { display: flex; align-items: center; gap: 10px; font-size: 0.95rem; color: var(--white); cursor: pointer; }

  .calc-row input[type="checkbox"] { width: 18px; height: 18px; accent-color: var(--sun); cursor: pointer; }

  .calc-row .wh { font-family: 'IBM Plex Mono', monospace; font-size: 0.82rem; color: var(--muted); white-space: nowrap; }

  .calc-result {
    margin-top: 18px; padding-top: 20px; border-top: 1px solid rgba(255,184,0,0.2);
    text-align: center;
  }

  .calc-result .total { font-family: 'Syne', sans-serif; font-size: 2.2rem; font-weight: 800; color: var(--sun); }

  .calc-result .tier { font-size: 0.95rem; color: #B8CFEA; margin-top: 8px; }

  .calc-result .tier strong { color: var(--white); }

  .tier-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin: 24px 0; }

  .tier-card {
    background: var(--card-bg); border: 1px solid rgba(255,255,255,0.08);
    border-radius: 12px; padding: 20px;
  }

  .tier-card .num {
    font-family: 'IBM Plex Mono', monospace; font-size: 0.72rem; letter-spacing: 0.1em;
    color: var(--sun); text-transform: uppercase; display: block; margin-bottom: 10px;
  }

  .tier-card h3 { font-family: 'Syne', sans-serif; font-size: 1.05rem; margin: 0 0 8px; color: var(--white); }

  .tier-card p { color: #B8CFEA; font-size: 0.9rem; margin-bottom: 0; }

  @media (max-width: 900px) {
  .nav-guides-panel {
      position: fixed; left: 16px; right: 16px; top: 92px;
      width: auto; max-width: none;
      flex-direction: column; gap: 18px;
    }
  .article-wrap { grid-template-columns: 1fr; gap: 32px; padding: 40px 20px 60px; }
  .sidebar { position: static; order: 2; }
  .sidebar-card:first-child { display: none; }
  }

  @media (max-width: 600px) {
  .nav { padding: 12px 16px; flex-wrap: wrap; row-gap: 10px; }
  .nav-logo { font-size: 1.1rem; }
  .nav-home { font-size: 0.78rem; padding: 5px 12px; }
  .nav-left { gap: 10px; }
  .nav-burger { width: 34px; height: 34px; }
  .nav-guides-panel { max-height: 70vh; overflow-y: auto; }
  .article-hero { padding: 90px 16px 36px; }
  .article-hero h1 { font-size: 1.85rem; line-height: 1.2; }
  .update-badge { font-size: 0.78rem; padding: 7px 14px; }
  .article-meta { gap: 10px; font-size: 0.78rem; }
  .breadcrumb { font-size: 0.74rem; }
  .article-wrap { padding: 28px 16px 48px; gap: 24px; }
  .article-body h2 { font-size: 1.25rem; margin: 32px 0 12px; padding-top: 32px; }
  .article-body h3 { font-size: 1rem; }
  .article-body p { font-size: 0.96rem; }
  .callout { padding: 14px; gap: 10px; flex-direction: row; }
  .callout-icon { font-size: 1rem; }
  .callout-title { font-size: 0.86rem; }
  .callout-text { font-size: 0.83rem; }
  .step-list { padding-left: 18px; }
  .step-item::before { left: -26px; width: 20px; height: 20px; font-size: 0.7rem; }
  .compare-table { min-width: 500px; font-size: 0.8rem; }
  .compare-table th, .compare-table td { padding: 9px 10px; }
  .product-cta { padding: 16px; margin: 20px 0; }
  .btn-amazon { width: 100%; justify-content: center; font-size: 0.9rem; padding: 13px 16px; }
  .sidebar-card { padding: 16px; margin-bottom: 12px; }
  footer { padding: 24px 16px; }
  .disclaimer { padding: 20px 16px; font-size: 0.77rem; }
  .compare-table-outer { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 16px -16px; padding: 0 16px 8px; }
  .product-cta h3 { font-size: 0.98rem; }
  .product-cta p { font-size: 0.85rem; }
  .sidebar-title { font-size: 0.84rem; margin-bottom: 10px; }
  .toc-list a { font-size: 0.82rem; }
  .sidebar-stat { font-size: 0.81rem; padding: 7px 0; }
  .sidebar-product-icon { width: 38px; height: 38px; font-size: 1rem; }
  .sidebar-product-name { font-size: 0.81rem; }
  .sidebar-product-desc { font-size: 0.74rem; }
  .article-body ul { padding-left: 18px; }
  .article-body ul li { font-size: 0.94rem; line-height: 1.9; }
  .timeline { padding-left: 18px; }
  .timeline-item::before { left: -15px; width: 8px; height: 8px; }
  .timeline-date { font-size: 0.72rem; }
  .timeline-title { font-size: 0.9rem; }
  .timeline-desc { font-size: 0.83rem; }
  .month-row { grid-template-columns: 44px 1fr 68px; gap: 10px; }
  .month-label { font-size: 0.72rem; }
  .month-value { font-size: 0.82rem; }
  .versus-card { padding: 16px; }
  .versus-card h4 { font-size: 0.96rem; }
  .versus-list li { font-size: 0.84rem; }
  .cost-row { grid-template-columns: 95px 1fr 75px; gap: 8px; font-size: 0.78rem; }
  .cost-bar { height: 18px; }
  .calc-row { padding: 10px 0; }
  }

  @media (max-width: 700px) {
  .versus-grid { grid-template-columns: 1fr; }
  }