/* ── RESET & BASE ── */
  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }

  body {
    font-family: var(--font-sans);
    font-size: calc(var(--body-sm-font-size) * 1px);
    line-height: calc(var(--body-sm-line-height) * 1px);
    color: var(--color-gray-900);
    background: var(--surface-page-light);
    -webkit-font-smoothing: antialiased;
  }

  /* ── SITE HEADER ── */
  .site-header {
    background: var(--color-gray-950);
    position: sticky;
    top: 0;
    z-index: 100;
    height: 56px;
    padding: 0 40px;
  }
  .header-inner {
    max-width: 1200px;
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    gap: 32px;
  }
  .site-header .logo {
    text-decoration: none;
    display: flex;
    align-items: center;
    flex-shrink: 0;
  }
  .site-header .logo img {
    height: 44px;
    width: auto;
    display: block;
  }
  .header-nav {
    display: flex;
    gap: 24px;
    align-items: center;
    margin-left: auto;
  }
  .header-nav a {
    font-size: 13px;
    color: var(--color-gray-400);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.15s;
  }
  .header-nav a:hover { color: #fff; }
  .header-nav a.nav-active { color: #fff; font-weight: 600; }
  .header-hotline {
    display: flex;
    align-items: center;
    gap: 7px;
    font-size: 13px;
    font-weight: var(--fw-semibold);
    color: var(--color-gray-300);
    white-space: nowrap;
    letter-spacing: 0.01em;
    margin-left: auto;
  }
  .header-hotline svg { flex-shrink: 0; }
  a.header-hotline { text-decoration: none; transition: color 0.15s; }
  a.header-hotline:hover { color: #fff; }
  a.header-hotline:hover svg { stroke: #fff; }

  /* ── LANGUAGE SWITCHER ── */
  .lang-switcher {
    position: relative;
  }
  .lang-btn {
    display: flex;
    align-items: center;
    gap: 5px;
    background: none;
    border: 1px solid var(--color-gray-700);
    border-radius: calc(var(--radius-sm) * 1px);
    color: var(--color-gray-300);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.06em;
    padding: 5px 10px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s;
    white-space: nowrap;
  }
  .lang-btn:hover { border-color: var(--color-gray-500); color: #fff; }
  .lang-btn svg { transition: transform 0.2s; }
  .lang-switcher.open .lang-btn svg { transform: rotate(180deg); }
  .lang-btn.active { border-color: var(--color-gray-500); color: #fff; }

  .lang-dropdown {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--color-gray-900);
    border: 1px solid var(--color-gray-750);
    border-radius: calc(var(--radius-md) * 1px);
    min-width: 140px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.4);
    overflow: hidden;
    z-index: 200;
  }
  .lang-switcher.open .lang-dropdown { display: block; }
  .lang-option {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 11px 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-gray-300);
    text-decoration: none;
    transition: background 0.12s, color 0.12s;
    border-bottom: 1px solid var(--color-gray-800);
  }
  .lang-option:last-child { border-bottom: none; }
  .lang-option:hover { background: var(--color-gray-800); color: #fff; }
  .lang-option.current { color: #fff; font-weight: 600; }
  .lang-option .lang-code {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--color-gray-600);
    margin-left: 12px;
  }
  .lang-option.current .lang-code { color: var(--color-yellow-500); }

  /* ── HERO ── */
  .page-hero {
    background: var(--color-gray-950);
    color: #fff;
    padding: 48px 40px;
  }
  .hero-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: end;
    gap: 32px;
  }
  .hero-eyebrow {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--color-yellow-500);
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
  }
  .hero-eyebrow::before {
    content: '';
    display: block;
    width: 20px;
    height: 2px;
    background: var(--color-yellow-500);
    border-radius: 2px;
    flex-shrink: 0;
  }
  .page-hero h1 {
    font-size: 36px;
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.01em;
    color: #fff;
    margin-bottom: 14px;
  }
  .page-hero p {
    font-size: 15px;
    line-height: 1.6;
    color: var(--color-gray-400);
    max-width: 540px;
  }
  .hero-meta {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 8px;
  }
  .hero-badge {
    background: var(--color-gray-850);
    border: 1px solid var(--color-gray-700);
    border-radius: calc(var(--radius-full) * 1px);
    padding: 6px 14px;
    font-size: 12px;
    font-weight: 500;
    color: var(--color-gray-400);
    white-space: nowrap;
  }
  .hero-badge strong { color: #fff; font-weight: 600; }

  /* ── MOBILE PILL NAV (shown when sidebar hides) ── */
  .mobile-nav {
    display: none;
    position: sticky;
    top: 56px;
    z-index: 90;
    background: #fff;
    border-bottom: 1px solid var(--color-gray-200);
    padding: 0 24px;
    gap: 0;
    overflow-x: auto;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
  }
  .mobile-nav::-webkit-scrollbar { display: none; }
  .mobile-nav-pill {
    flex-shrink: 0;
    padding: 12px 14px 11px;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-gray-600);
    text-decoration: none;
    border-bottom: 2px solid transparent;
    transition: color 0.12s, border-color 0.12s;
    white-space: nowrap;
  }
  .mobile-nav-pill:hover { color: var(--color-gray-900); }
  .mobile-nav-pill.active {
    color: var(--color-gray-900);
    font-weight: 600;
    border-bottom-color: var(--color-yellow-500);
  }

  /* ── LAYOUT ── */
  .page-layout {
    max-width: 1200px;
    margin: 0 auto;
    padding: 48px 40px 80px;
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 48px;
    align-items: start;
  }

  /* ── SIDEBAR ── */
  .sidebar {
    position: sticky;
    top: 72px;
  }
  .toc-label {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--color-gray-500);
    margin-bottom: 12px;
  }
  .toc {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 2px;
  }
  .toc a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 7px 10px;
    font-size: 13px;
    color: var(--color-gray-700);
    text-decoration: none;
    border-radius: calc(var(--radius-sm) * 1px);
    font-weight: 500;
    transition: color 0.12s, background 0.12s;
  }
  .toc a:hover {
    color: var(--color-gray-900);
    background: var(--color-gray-200);
  }
  .toc a.active {
    color: var(--color-gray-900);
    background: var(--color-yellow-100);
    font-weight: 600;
  }
  .toc a.active::before {
    content: '';
    display: block;
    width: 3px;
    height: 14px;
    background: var(--color-yellow-500);
    border-radius: 2px;
    flex-shrink: 0;
  }
  .toc-divider {
    height: 1px;
    background: var(--color-gray-200);
    margin: 10px 10px;
  }
  .toc-support {
    margin-top: 20px;
    background: var(--color-gray-150);
    border-radius: calc(var(--radius-lg) * 1px);
    padding: 16px;
  }
  .toc-support-label {
    font-size: 11px;
    font-weight: 600;
    color: var(--color-gray-700);
    margin-bottom: 6px;
  }
  .toc-support p {
    font-size: 12px;
    color: var(--color-gray-700);
    line-height: 1.5;
    margin-bottom: 10px;
  }
  .toc-support a {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-yellow-deep-500);
    text-decoration: none;
  }
  .toc-support a:hover { text-decoration: underline; }

  /* ── MAIN CONTENT ── */
  .main-content {
    display: flex;
    flex-direction: column;
    gap: 64px;
    min-width: 0;
  }

  /* ── SECTION HEADER ── */
  .section-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--color-gray-200);
  }
  .section-icon {
    width: 38px; height: 38px;
    background: var(--color-yellow-500);
    border-radius: calc(var(--radius-md) * 1px);
    display: flex; align-items: center; justify-content: center;
    font-size: 13px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-gray-900);
    flex-shrink: 0;
    font-family: var(--font-sans);
  }
  .section-title {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-gray-900);
    letter-spacing: -0.01em;
  }
  .section-subtitle {
    font-size: 13px;
    color: var(--color-gray-700);
    font-weight: 400;
    margin-top: 2px;
  }

  /* ── INTRO SECTION ── */
  .intro-text {
    font-size: 15px;
    line-height: 1.7;
    color: var(--color-gray-700);
    margin-bottom: 24px;
    text-wrap: pretty;
    max-width: 640px;
  }
  .intro-text p + p { margin-top: 12px; }

  /* ── STEPS ── */
  .steps-list {
    display: flex;
    flex-direction: column;
    gap: 0;
  }
  .step {
    display: grid;
    grid-template-columns: 48px 1fr;
    gap: 0 18px;
    position: relative;
  }
  .step + .step { margin-top: 20px; }

  .step-num-col {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0;
  }
  .step-num {
    width: 38px; height: 38px;
    background: var(--color-yellow-500);
    color: var(--color-gray-900);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 15px;
    font-weight: 700;
    flex-shrink: 0;
    letter-spacing: 0;
    box-shadow: 0 0 0 4px var(--color-yellow-100);
  }
  .step-connector {
    width: 2px;
    flex: 1;
    background: var(--color-gray-200);
    margin: 4px 0;
    min-height: 12px;
  }
  .step:last-child .step-connector { display: none; }

  .step-card {
    background: #fff;
    border: 1px solid var(--color-gray-200);
    border-radius: calc(var(--radius-lg) * 1px);
    padding: 20px;
    margin-bottom: 20px;
    transition: border-color 0.15s;
  }
  .step-card:hover { border-color: var(--color-gray-300); }

  .step-card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 0;
  }
  .step-card-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--color-gray-900);
    line-height: 1.4;
  }

  .step-card-body {
    font-size: 14px;
    color: var(--color-gray-700);
    line-height: 1.65;
    margin-top: 8px;
    text-wrap: pretty;
  }

  /* Sub-steps */
  .sub-steps {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-top: 12px;
  }
  .sub-steps li {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 14px;
    background: var(--color-gray-100);
    border-radius: calc(var(--radius-md) * 1px);
    font-size: 13.5px;
    color: var(--color-gray-800);
    line-height: 1.5;
    border-left: 3px solid var(--color-yellow-400);
  }
  .sub-label {
    font-weight: 600;
    color: var(--color-gray-900);
    white-space: nowrap;
  }
  /* Diagram sub-steps */
  .diagram-steps li {
    flex-direction: column;
    gap: 0;
    padding: 0;
    overflow: hidden;
    border: 1px solid var(--color-gray-200);
    border-left: 1px solid var(--color-gray-200);
    border-radius: calc(var(--radius-md) * 1px);
    cursor: zoom-in;
    -webkit-tap-highlight-color: transparent;
    transition: background 0.12s, border-color 0.15s;
  }
  .diagram-steps li:hover { border-color: var(--color-gray-300); background: var(--color-gray-50); }
  .diagram-steps li:active { background: var(--color-gray-100); }
  .sub-step-content {
    display: flex;
    flex-direction: column;
    width: 100%;
  }
  .sub-step-content > div {
    padding: 10px 14px 8px;
  }
  .hook-diagram {
    width: 100%;
    height: auto;
    display: block;
    border-top: 1px solid var(--color-gray-200);
    background: #fff;
  }
  /* Diagram tap/click affordance */
  .hook-diagram-wrap { position: relative; line-height: 0; }
  .hook-diagram-expand-hint {
    position: absolute;
    bottom: 8px; right: 8px;
    width: 28px; height: 28px;
    background: rgba(0,0,0,0.45);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    border-radius: 6px;
    display: flex; align-items: center; justify-content: center;
    pointer-events: none;
  }
  /* Placeholder shown when a diagram image is not yet present */
  .hook-diagram-placeholder {
    width: 100%;
    aspect-ratio: 3 / 1;
    border-top: 1px solid var(--color-gray-200);
    background:
      repeating-linear-gradient(45deg,
        var(--color-gray-100), var(--color-gray-100) 14px,
        var(--color-gray-150) 14px, var(--color-gray-150) 28px);
    display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    gap: 4px; padding: 16px; text-align: center;
  }
  .hook-diagram-placeholder strong {
    font-size: 13px; font-weight: 700; color: var(--color-gray-600);
  }
  .hook-diagram-placeholder span {
    font-size: 11px; font-weight: 500; color: var(--color-gray-450);
  }

  .step-note {
    display: flex;
    gap: 10px;
    margin-top: 12px;
    padding: 10px 14px;
    background: var(--color-gray-100);
    border-radius: calc(var(--radius-md) * 1px);
    font-size: 12.5px;
    color: var(--color-gray-700);
    line-height: 1.5;
    border-left: 3px solid var(--color-gray-350);
  }
  .step-note strong { color: var(--color-gray-900); font-weight: 600; }
  .step-note-icon { flex-shrink: 0; margin-top: 2px; line-height: 0; display: flex; }

  /* ── WARNING ── */
  .warning-block {
    background: var(--color-orange-50);
    border: 1.5px solid var(--color-orange-300);
    border-radius: calc(var(--radius-lg) * 1px);
    padding: 24px 32px;
  }
  .warning-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 14px;
  }
  .warning-icon {
    width: 34px; height: 34px;
    background: var(--color-orange-500);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: #fff;
    font-size: 15px;
    flex-shrink: 0;
  }
  .warning-title {
    font-size: 15px;
    font-weight: 700;
    color: var(--color-orange-700);
    letter-spacing: 0.02em;
    text-transform: uppercase;
  }
  .warning-text {
    font-size: 13.5px;
    color: var(--color-orange-700);
    line-height: 1.65;
  }
  .warning-text p + p { margin-top: 10px; }
  .warning-text strong { font-weight: 700; color: var(--color-orange-800); }

  /* ── MAINTENANCE COLS ── */
  .maint-cols {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    margin-bottom: 24px;
    background: #fff;
    border: 1px solid var(--color-gray-200);
    border-radius: calc(var(--radius-lg) * 1px);
    overflow: hidden;
  }
  .maint-col {
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    border-right: 1px solid var(--color-gray-150);
  }
  .maint-col:last-child { border-right: none; }
  .maint-col-tag {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-gray-650);
  }
  .maint-col-title {
    font-size: 15px;
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: 4px;
  }
  .maint-col-text {
    font-size: 13px;
    color: var(--color-gray-700);
    line-height: 1.6;
  }

  .rules-list {
    list-style: none;
    background: #fff;
    border: 1px solid var(--color-gray-200);
    border-radius: calc(var(--radius-lg) * 1px);
    overflow: hidden;
  }
  .rules-list li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 18px;
    font-size: 13px;
    color: var(--color-gray-700);
    line-height: 1.5;
    border-bottom: 1px solid var(--color-gray-100);
  }
  .rules-list li:last-child { border-bottom: none; }
  .rule-icon {
    font-size: 13px;
    font-weight: 700;
    flex-shrink: 0;
    width: 18px;
    margin-top: 1px;
  }
  .rule-icon.no { color: var(--color-red-500); }
  .rule-icon.yes { color: var(--color-green-500); }

  .material-note {
    margin-top: 20px;
    background: var(--color-gray-100);
    border-radius: calc(var(--radius-lg) * 1px);
    padding: 16px 20px;
    font-size: 13px;
    color: var(--color-gray-600);
    line-height: 1.6;
  }
  .material-note strong { color: var(--color-gray-800); font-weight: 600; }

  /* ── DRIVER WARNING ── */
  .driver-warning {
    display: flex;
    gap: 14px;
    padding: 16px 20px;
    background: var(--color-orange-50);
    border: 1.5px solid var(--color-orange-300);
    border-radius: calc(var(--radius-lg) * 1px);
    margin-top: 12px;
  }
  .driver-warning-icon {
    width: 32px; height: 32px;
    background: var(--color-orange-100);
    border-radius: calc(var(--radius-sm) * 1px);
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0; margin-top: 1px;
  }
  .driver-warning-title {
    font-size: 14px; font-weight: 700;
    color: var(--color-orange-800);
    margin-bottom: 4px;
  }
  .driver-warning-text {
    font-size: 13px;
    color: var(--color-orange-700);
    line-height: 1.6;
  }
  .driver-warning-link {
    display: inline-block; margin-top: 8px;
    font-size: 13px; font-weight: 600;
    color: var(--color-orange-700);
    text-decoration: underline; text-underline-offset: 2px;
  }

  /* ── SUPPORT CONTACT ── */
  .support-contact {
    background: var(--color-gray-950);
    border-radius: calc(var(--radius-xl) * 1px);
    padding: 40px 48px;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 48px;
    align-items: center;
  }
  .support-contact h3 {
    font-size: 20px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 8px;
  }
  .support-contact p {
    font-size: 14px;
    color: var(--color-gray-400);
    line-height: 1.6;
    max-width: 380px;
  }
  .support-channels { display: flex; flex-direction: column; gap: 10px; }
  .support-channel {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 20px;
    background: var(--color-gray-850);
    border-radius: calc(var(--radius-md) * 1px);
    text-decoration: none;
    min-width: 296px;
    transition: background 0.15s;
    border: 1px solid var(--color-gray-800);
  }
  .support-channel:hover { background: var(--color-gray-800); }
  .support-channel-icon {
    width: 36px; height: 36px;
    background: rgba(255,255,255,0.08);
    border-radius: calc(var(--radius-sm) * 1px);
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
  }
  .support-channel-label {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-gray-400);
  }
  .support-channel-value {
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    margin-top: 1px;
  }

  /* ── SITE FOOTER ── */
  .site-footer {
    background: var(--color-gray-150);
    border-top: 1px solid var(--color-gray-200);
    padding: 20px 40px;
  }
  .footer-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
  }
  .footer-left {
    display: flex;
    align-items: center;
    gap: 16px;
  }
  .footer-copyright {
    font-size: 12px;
    color: var(--color-gray-500);
    white-space: nowrap;
  }
  .footer-links {
    display: flex;
    align-items: center;
    gap: 24px;
  }
  .footer-links a {
    font-size: 12px;
    color: var(--color-gray-600);
    text-decoration: none;
    transition: color 0.12s;
  }
  .footer-links a:hover { color: var(--color-gray-900); }

  /* ── LIGHTBOX (diagram viewer) ── */
  .lb-overlay {
    position: fixed;
    inset: 0;
    z-index: 600;
    background: #000;
    display: flex;
    flex-direction: column;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.22s ease;
    touch-action: none;
    user-select: none;
    -webkit-user-select: none;
  }
  .lb-overlay.lb-open { opacity: 1; pointer-events: all; }
  .lb-header {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 16px;
    padding-top: max(14px, calc(env(safe-area-inset-top) + 10px));
  }
  .lb-counter {
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: rgba(255,255,255,0.35);
  }
  .lb-close {
    width: 36px; height: 36px;
    background: rgba(255,255,255,0.1);
    border: none;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
    flex-shrink: 0;
  }
  .lb-close:hover { background: rgba(255,255,255,0.2); }
  .lb-close:active { background: rgba(255,255,255,0.22); }
  .lb-stage { flex: 1; overflow: hidden; position: relative; }
  .lb-track {
    display: flex;
    align-items: center;
    height: 100%;
    will-change: transform;
  }
  .lb-slide {
    flex-shrink: 0;
    width: 100vw;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 24px;
  }
  .lb-slide img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 10px;
    pointer-events: none;
    -webkit-user-drag: none;
    display: block;
  }
  .lb-footer {
    flex-shrink: 0;
    padding: 16px 20px;
    padding-bottom: max(18px, calc(env(safe-area-inset-bottom) + 14px));
  }
  .lb-cap-label {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-yellow-500);
    margin-bottom: 5px;
  }
  .lb-cap-text {
    font-size: 13px;
    line-height: 1.55;
    color: rgba(255,255,255,0.62);
    text-wrap: pretty;
    max-width: 640px;
  }
  .lb-dots {
    display: flex;
    gap: 7px;
    justify-content: center;
    margin-top: 16px;
  }
  .lb-dot {
    width: 7px; height: 7px;
    border-radius: 50%;
    border: none;
    padding: 0;
    background: rgba(255,255,255,0.2);
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
    transition: background 0.15s, transform 0.15s;
  }
  .lb-dot.lb-dot-on { background: var(--color-yellow-500); transform: scale(1.35); }
  .lb-pull-bar {
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 32px; height: 3px;
    background: rgba(255,255,255,0.18);
    border-radius: 2px;
  }

  /* ── RESPONSIVE: tablet / collapse sidebar ── */
  @media (max-width: 900px) {
    .page-layout { grid-template-columns: 1fr; padding: 32px 24px 64px; }
    .sidebar { position: static; display: none; }
    .mobile-nav { display: flex; }
    .hero-inner { grid-template-columns: 1fr; }
    .hero-meta { align-items: flex-start; flex-direction: row; flex-wrap: wrap; }
    .page-hero { padding: 40px 24px 36px; }
    .maint-cols { grid-template-columns: 1fr; }
    .maint-col { border-right: none; border-bottom: 1px solid var(--color-gray-150); }
    .maint-col:last-child { border-bottom: none; }
    .driver-warning { margin-top: 10px; }
    .support-contact { grid-template-columns: 1fr; gap: 24px; padding: 28px; }
    .support-channel { min-width: 0; width: 100%; }
    .site-footer { padding: 16px 24px; }
    .footer-inner { flex-direction: column; align-items: flex-start; gap: 12px; }
    .site-header { padding: 0 24px; }
    .header-nav { display: none; }
    .header-hotline { display: none; }
    .lang-switcher { display: flex; }
    .lang-dropdown { right: -8px; }
  }

  /* ── RESPONSIVE: phone (match mobile comp) ── */
  @media (max-width: 600px) {
    body { font-size: 15px; line-height: 22px; }
    .site-header { height: 52px; padding: 0 20px; }
    .header-inner { gap: 12px; }
    .site-header .logo img { height: 32px; }
    .mobile-nav { top: 52px; padding: 0 20px; }

    .page-hero { padding: 28px 20px 24px; }
    .hero-eyebrow { font-size: 10px; letter-spacing: 0.16em; margin-bottom: 10px; }
    .hero-eyebrow::before { width: 16px; }
    .page-hero h1 { font-size: 28px; margin-bottom: 10px; }
    .page-hero p { font-size: 14px; margin-bottom: 0; }
    .hero-inner { gap: 16px; }
    .hero-meta { gap: 8px; margin-top: 2px; }
    .hero-badge { padding: 5px 12px; font-size: 11px; }

    .page-layout { padding: 32px 20px 64px; }
    .main-content { gap: 48px; }

    .section-header { gap: 14px; margin-bottom: 20px; padding-bottom: 14px; }
    .section-icon { width: 36px; height: 36px; font-size: 12px; }
    .section-title { font-size: 20px; }
    .section-subtitle { font-size: 12px; margin-top: 2px; }

    .intro-text { font-size: 14px; margin-bottom: 0; }

    .step { grid-template-columns: 40px 1fr; gap: 0 14px; }
    .step + .step { margin-top: 16px; }
    .step-num { width: 34px; height: 34px; font-size: 14px; box-shadow: 0 0 0 3px var(--color-yellow-100); }
    .step-card { padding: 16px; margin-bottom: 16px; }
    .step-card-title { font-size: 14px; }
    .step-card-body { font-size: 13px; line-height: 1.6; margin-top: 7px; }
    .sub-steps { gap: 8px; }
    .sub-steps li { font-size: 13px; }
    .step-note { font-size: 12px; }

    .warning-block { padding: 20px; }
    .warning-title { font-size: 13px; }
    .warning-text { font-size: 13px; }

    .maint-col { padding: 16px 20px; }
    .maint-col-title { font-size: 14px; }

    .driver-warning { padding: 14px 16px; }
    .driver-warning-title { font-size: 13px; }
    .driver-warning-text { font-size: 12px; }

    .support-contact { padding: 24px 20px; border-radius: calc(var(--radius-xl) * 1px); }
    .support-contact h3 { font-size: 18px; }
    .support-contact p { font-size: 13px; }
    .support-channel { padding: 12px 16px; }
  }