:root{
    --color-primary:#344F90;
    --color-secondary:#0055A7;
    --color-secondary-hover:#00468C;
    --color-muted:#9EABCA;
    --color-bg:#F5F7FA;
    --color-surface:#FFFFFF;
    --color-text:#1A2333;
    --color-text-muted:#5B667A;
    --color-border:#D9DFEA;
    --color-success:#2E9E5B;
    --color-warning:#C98A1F;
    --color-error:#C0392B;
    --radius-sm:6px;
    --radius-md:10px;
    --radius-lg:16px;
    --container:1240px;
    --font: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  }

  *{box-sizing:border-box; margin:0; padding:0;}
  html{scroll-behavior:smooth;}
  body{
    font-family:var(--font);
    color:var(--color-text);
    background:var(--color-bg);
    line-height:1.55;
    -webkit-font-smoothing:antialiased;
  }
  img{display:block; max-width:100%; height:auto;}
  a{color:inherit; text-decoration:none;}
  ul{list-style:none;}
  button, input, select{font-family:inherit; font-size:inherit;}

  .wrap{max-width:var(--container); margin:0 auto; padding:0 24px;}
  section{padding:72px 0;}
  @media (max-width:640px){ section{padding:48px 0;} }

  h1,h2,h3,h4{font-weight:700; line-height:1.15; color:var(--color-text);}
  h1{font-size:clamp(32px,4vw,46px); font-weight:800;}
  h2{font-size:clamp(26px,3vw,32px);}
  h3{font-size:20px;}
  p{color:var(--color-text-muted);}
  .eyebrow{
    display:inline-block; font-size:13px; font-weight:600; letter-spacing:.06em;
    text-transform:uppercase; color:var(--color-secondary); margin-bottom:10px;
  }
  .section-head{max-width:640px; margin-bottom:40px;}
  .section-head p{margin-top:12px; font-size:16px;}

  /* ---------- Buttons ---------- */
  .btn{
    display:inline-flex; align-items:center; justify-content:center; gap:8px;
    padding:14px 26px; border-radius:var(--radius-sm); font-weight:600; font-size:15px;
    border:1px solid transparent; cursor:pointer; transition:background .15s ease, border-color .15s ease, color .15s ease;
    white-space:nowrap;
  }
  .btn-primary{background:var(--color-secondary); color:#fff;}
  .btn-primary:hover{background:var(--color-secondary-hover);}
  .btn-outline{background:transparent; border-color:var(--color-muted); color:var(--color-text);}
  .btn-outline:hover{border-color:var(--color-secondary); color:var(--color-secondary);}
  .btn-outline-on-dark{background:transparent; border-color:rgba(255,255,255,.5); color:#fff;}
  .btn-outline-on-dark:hover{border-color:#fff; background:rgba(255,255,255,.08);}
  .btn-white{background:#fff; color:var(--color-primary);}
  .btn-white:hover{background:#EDF1F8;}
  .btn-block{width:100%;}
  .btn:focus-visible{outline:3px solid rgba(0,85,167,.4); outline-offset:2px;}

  /* ---------- Image placeholder containers ----------
     These are the containers you asked for: fixed-ratio divs with an <img> inside,
     sized explicitly. To drop in a real photo, just replace src="PLACEHOLDER"
     with your image URL — the JS at the bottom only touches images still marked PLACEHOLDER. */
  .img-box{
    position:relative; width:100%; overflow:hidden; border-radius:var(--radius-md);
    background:var(--color-border);
  }
  .img-box img{width:100%; height:100%; object-fit:cover; display:block;}
  .ratio-16-9{aspect-ratio:16/9;}
  .ratio-4-3{aspect-ratio:4/3;}
  .ratio-1-1{aspect-ratio:1/1;}
  .ratio-3-2{aspect-ratio:3/2;}

  /* ---------- Header ---------- */
  header{
    position:sticky; top:0; z-index:50; background:#fff; border-bottom:1px solid var(--color-border);
  }
  .header-inner{display:flex; align-items:center; justify-content:space-between; gap:24px; height:76px; position:relative;}
  .logo{display:flex; align-items:center; gap:10px; font-weight:800; font-size:19px; color:var(--color-primary);}
  .logo .logo-mark{width:34px; height:34px; border-radius:8px; background:var(--color-secondary); flex-shrink:0;}
  .nav-actions-wrap{display:flex; align-items:center; gap:32px;}
  nav.primary-nav{display:flex; align-items:center; gap:32px;}
  nav.primary-nav a{font-weight:500; font-size:15px; color:var(--color-text);}
  nav.primary-nav a:hover{color:var(--color-secondary);}
  nav.primary-nav a.active{color:var(--color-secondary); font-weight:700;}
  .header-actions{display:flex; align-items:center; gap:12px;}
  .mobile-toggle{display:none; background:none; border:none; cursor:pointer; padding:8px; z-index:70;}
  .mobile-toggle span{display:block; width:22px; height:2px; background:var(--color-text); margin:5px 0; transition:transform .2s ease, opacity .2s ease;}

  @media (max-width:960px){
    .nav-actions-wrap{display:none;}
    .mobile-toggle{display:block;}

    header.nav-open .nav-actions-wrap{
      display:flex; flex-direction:column; align-items:stretch; gap:0;
      position:absolute; top:76px; left:0; right:0; background:#fff;
      border-bottom:1px solid var(--color-border); padding:8px 24px 22px; z-index:60;
      box-shadow:0 12px 24px rgba(26,35,51,.08);
    }
    header.nav-open .nav-actions-wrap .primary-nav{
      flex-direction:column; align-items:stretch; gap:0;
    }
    header.nav-open .nav-actions-wrap .primary-nav a{
      padding:14px 2px; border-bottom:1px solid var(--color-border);
    }
    header.nav-open .nav-actions-wrap .header-actions{
      flex-direction:column; align-items:stretch; gap:10px; padding-top:16px;
    }
    header.nav-open .nav-actions-wrap .header-actions .btn{width:100%;}

    header.nav-open .mobile-toggle span:nth-child(1){transform:translateY(7px) rotate(45deg);}
    header.nav-open .mobile-toggle span:nth-child(2){opacity:0;}
    header.nav-open .mobile-toggle span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}
  }

  /* ---------- Hero Banner (full-bleed slider / video background) ---------- */
  .hero-banner{
    position:relative;
    min-height:640px;
    display:flex;
    align-items:center;
    overflow:hidden;
    color:#fff;
    isolation:isolate; /* keeps overlay/content stacking self-contained */
  }
  .hero-media{position:absolute; inset:0; z-index:0;}

  /* Slider mode (default): cross-fading full-bleed images */
  .hero-slide{position:absolute; inset:0; opacity:0; transition:opacity 1.4s ease;}
  .hero-slide.active{opacity:1;}
  .hero-slide img{width:100%; height:100%; object-fit:cover; border-radius:0;}

  /* Video mode: add class "video-mode" to .hero-banner to use this instead of the slider — see HTML comment */
  .hero-video{position:absolute; inset:0; width:100%; height:100%; object-fit:cover; display:none;}
  .hero-banner.video-mode .hero-video{display:block;}
  .hero-banner.video-mode .hero-slide{display:none;}

  .hero-overlay{
    position:absolute; inset:0; z-index:1;
    background:linear-gradient(100deg, rgba(19,27,46,.86) 0%, rgba(19,27,46,.62) 46%, rgba(19,27,46,.28) 78%, rgba(19,27,46,.12) 100%);
  }
  .hero-content{position:relative; z-index:2; padding:110px 0 150px; width:100%;}
  .hero-content .eyebrow{color:#BFD0F0;}
  .hero-content h1{color:#fff;}
  .hero-content p.lead{font-size:18px; margin-top:16px; max-width:540px; color:#DCE3F1;}
  .hero-ctas{display:flex; gap:14px; margin-top:32px; flex-wrap:wrap;}
  .hero-note{margin-top:20px; font-size:13px; color:#BFD0F0; display:flex; align-items:center; gap:8px;}

  .hero-dots{
    position:absolute; z-index:2; bottom:28px; left:50%; transform:translateX(-50%);
    display:flex; gap:10px;
  }
  .hero-banner.video-mode .hero-dots{display:none;}
  .hero-dots button{
    width:9px; height:9px; border-radius:50%; border:none; background:rgba(255,255,255,.4); cursor:pointer; padding:0;
  }
  .hero-dots button.active{background:#fff; width:22px; border-radius:5px;}

  @media (max-width:900px){
    .hero-banner{min-height:560px;}
    .hero-content{padding:80px 0 130px;}
  }
  @media (max-width:560px){
    .hero-banner{min-height:520px;}
  }

  /* ---------- Spec Finder ---------- */
  .spec-finder-wrap{margin-top:-90px; position:relative; z-index:3;}
  @media (max-width:900px){ .spec-finder-wrap{margin-top:-60px;} }
  .spec-finder{
    background:var(--color-primary); border-radius:var(--radius-lg);
    padding:36px; color:#fff; box-shadow:0 24px 48px rgba(19,27,46,.28);
  }
  .spec-finder h3{color:#fff; font-size:18px; margin-bottom:4px;}
  .spec-finder .sub{color:#C9D3EA; font-size:14px; margin-bottom:22px;}
  .finder-grid{display:grid; grid-template-columns:repeat(5,1fr) auto; gap:14px; align-items:end;}
  .field label{display:block; font-size:12px; font-weight:600; letter-spacing:.03em; text-transform:uppercase; color:#C9D3EA; margin-bottom:6px;}
  .field select{
    width:100%; padding:12px 14px; border-radius:var(--radius-sm); border:1px solid rgba(255,255,255,.25);
    background:rgba(255,255,255,.08); color:#fff; appearance:none;
  }
  .field select option{color:#1A2333;}
  .finder-divider{grid-column:1/-1; display:flex; align-items:center; gap:14px; margin:22px 0 18px; color:#9FB0D6; font-size:13px;}
  .finder-divider::before, .finder-divider::after{content:""; flex:1; height:1px; background:rgba(255,255,255,.18);}
  .part-search{display:flex; gap:12px;}
  .part-search input{
    flex:1; padding:12px 14px; border-radius:var(--radius-sm); border:1px solid rgba(255,255,255,.25);
    background:rgba(255,255,255,.08); color:#fff;
  }
  .part-search input::placeholder{color:#9FB0D6;}
  @media (max-width:900px){
    .finder-grid{grid-template-columns:1fr 1fr;}
    .part-search{flex-direction:column;}
  }

  /* ---------- Category cards ---------- */
  .card-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:24px;}
  @media (max-width:960px){ .card-grid{grid-template-columns:repeat(2,1fr);} }
  @media (max-width:560px){ .card-grid{grid-template-columns:1fr;} }
  .cat-card{
    background:var(--color-surface); border:1px solid var(--color-border); border-radius:var(--radius-md);
    overflow:hidden; transition:box-shadow .15s ease, transform .15s ease;
  }
  .cat-card:hover{box-shadow:0 12px 28px rgba(26,35,51,.08); transform:translateY(-2px);}
  .cat-card .body{padding:20px;}
  .cat-card h3{margin-bottom:6px; font-size:17px;}
  .cat-card p{font-size:14px; margin-bottom:14px;}
  .cat-card .spec-tag{
    display:inline-block; font-size:12px; font-weight:600; color:var(--color-primary);
    background:rgba(158,171,202,.25); border:1px solid rgba(158,171,202,.5);
    padding:4px 10px; border-radius:20px; margin-bottom:14px;
  }
  .cat-card .cta-link{font-size:14px; font-weight:600; color:var(--color-secondary); display:inline-flex; align-items:center; gap:6px;}

  /* ---------- Why choose us ---------- */
  .feature-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:28px;}
  @media (max-width:960px){ .feature-grid{grid-template-columns:repeat(2,1fr);} }
  @media (max-width:560px){ .feature-grid{grid-template-columns:1fr;} }
  .feature{padding:4px;}
  .feature .icon{
    width:48px; height:48px; border-radius:12px; background:rgba(158,171,202,.28); color:var(--color-secondary);
    display:flex; align-items:center; justify-content:center; font-weight:800; font-size:18px; margin-bottom:16px;
    border:1px solid rgba(158,171,202,.4);
  }
  .feature h3{font-size:16px; margin-bottom:6px;}
  .feature p{font-size:14px;}

  /* ---------- Featured products ---------- */
  .product-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:24px;}
  @media (max-width:900px){ .product-grid{grid-template-columns:repeat(2,1fr);} }
  @media (max-width:560px){ .product-grid{grid-template-columns:1fr;} }
  .product-card{background:#fff; border:1px solid var(--color-border); border-radius:var(--radius-md); overflow:hidden;}
  .product-card .body{padding:20px;}
  .product-card .model{font-size:12px; font-weight:700; color:var(--color-muted); letter-spacing:.04em; text-transform:uppercase;}
  .product-card h3{margin:4px 0 12px;}
  .spec-list{display:grid; grid-template-columns:1fr 1fr; gap:8px 12px; margin-bottom:16px; border-top:1px solid var(--color-border); padding-top:14px;}
  .spec-list div{font-size:13px;}
  .spec-list dt{color:var(--color-muted); font-size:11px; text-transform:uppercase; letter-spacing:.03em; font-weight:600;}
  .spec-list dd{font-weight:600; color:var(--color-text);}
  .product-card .actions{display:flex; gap:10px;}
  .product-card .actions .btn{flex:1; padding:11px 14px; font-size:14px;}

  /* ---------- Trust ---------- */
  .trust-section{background:var(--color-surface); border-top:1px solid var(--color-border); border-bottom:1px solid var(--color-border);}
  .trust-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:32px; align-items:start;}
  @media (max-width:900px){ .trust-grid{grid-template-columns:repeat(2,1fr);} }
  .trust-item h3{font-size:15px; margin-bottom:6px;}
  .trust-item p{font-size:13px;}
  .badge-row{display:flex; gap:14px; flex-wrap:wrap; margin-top:20px;}
  .badge-box{width:84px; height:56px; border:1px solid var(--color-muted); background:#fff;}

  /* ---------- How it works ---------- */
  .steps{display:grid; grid-template-columns:repeat(5,1fr); gap:20px; counter-reset:step;}
  @media (max-width:900px){ .steps{grid-template-columns:repeat(2,1fr);} }
  @media (max-width:560px){ .steps{grid-template-columns:1fr;} }
  .step{position:relative; padding:24px 20px; background:#fff; border:1px solid var(--color-border); border-radius:var(--radius-md);}
  .step .num{
    width:32px; height:32px; border-radius:50%; background:var(--color-secondary); color:#fff;
    display:flex; align-items:center; justify-content:center; font-weight:700; font-size:14px; margin-bottom:14px;
  }
  .step h3{font-size:15px; margin-bottom:6px;}
  .step p{font-size:13px;}

  /* ---------- FAQ ---------- */
  .faq-list{max-width:820px;}
  .faq-item{border-bottom:1px solid var(--color-border);}
  .faq-item summary{
    cursor:pointer; padding:20px 4px; font-weight:600; font-size:16px; list-style:none;
    display:flex; justify-content:space-between; align-items:center; gap:16px;
  }
  .faq-item summary::-webkit-details-marker{display:none;}
  .faq-item summary::after{content:"+"; font-size:22px; color:var(--color-secondary); flex-shrink:0; transition:transform .15s ease;}
  .faq-item[open] summary::after{transform:rotate(45deg);}
  .faq-item .a{padding:0 4px 20px; font-size:14px; max-width:680px;}

  /* ---------- Final CTA ---------- */
  .final-cta{
    background:var(--color-primary); border-radius:var(--radius-lg); padding:56px; text-align:center; color:#fff;
  }
  .final-cta h2{color:#fff;}
  .final-cta p{color:#C9D3EA; max-width:520px; margin:14px auto 28px; font-size:16px;}

  /* ---------- Footer ---------- */
  footer{background:#131B2E; color:#B9C3D6; padding:64px 0 28px;}
  .footer-grid{display:grid; grid-template-columns:2fr 1fr 1fr 1fr; gap:40px; margin-bottom:48px;}
  @media (max-width:900px){ .footer-grid{grid-template-columns:1fr 1fr; row-gap:32px;} }
  footer h4{color:#fff; font-size:14px; margin-bottom:16px; letter-spacing:.02em;}
  footer ul li{margin-bottom:10px; font-size:14px;}
  footer ul li a:hover{color:#fff;}
  footer .logo{color:#fff; margin-bottom:14px;}
  footer .foot-desc{font-size:14px; max-width:280px; margin-bottom:16px;}
  .footer-bottom{
    border-top:1px solid rgba(255,255,255,.08); padding-top:24px; display:flex; justify-content:space-between;
    flex-wrap:wrap; gap:12px; font-size:13px;
  }

  @media (prefers-reduced-motion: reduce){
    *{animation:none !important; transition:none !important;}
  }

  /* ---------- Small layout utilities (replacing inline styles) ---------- */
  .section-alt{background:var(--color-surface); border-top:1px solid var(--color-border); border-bottom:1px solid var(--color-border);}
  .section-alt-top{background:var(--color-surface); border-top:1px solid var(--color-border);}
  .pt-lg{padding-top:120px;}
  .footer-brand{display:flex; align-items:center; gap:10px; font-weight:800; font-size:18px; color:#fff; margin-bottom:14px;}
  .footer-brand .logo-mark{width:30px; height:30px; border-radius:8px; background:var(--color-secondary);}
  .footer-contact{font-size:14px;}