:root{
    --bg:#0b0d12; --bg2:#0f131b; --paper:#ffffff; --ink:#14181f; --sub:#3d4756; --mut:#6b7686;
    --line:#e6e9ef; --line2:#eef1f5; --brand:#ff2d55; --brand2:#6366f1;
    --ok:#10b981; --warn:#ff2d55; --chip:#f2f3f8; --amber:#b7791f;
    --grad:linear-gradient(120deg,#ff2d55 0%,#ff5e3a 45%,#f7b500 100%);
    --grad2:linear-gradient(135deg,#6366f1,#8b5cf6);
    --glass:rgba(255,255,255,.06);
    --shadow:0 18px 50px -20px rgba(16,20,40,.28);
  }
  *{box-sizing:border-box;margin:0;padding:0}
  html{scroll-behavior:smooth}

  /* accessibility: skip link */
  .skip{position:absolute;left:-9999px;top:0;z-index:100;background:#fff;color:var(--ink);
    padding:12px 18px;border-radius:0 0 10px 0;font-weight:700;box-shadow:var(--shadow)}
  .skip:focus{left:0}
  :focus-visible{outline:3px solid var(--brand2);outline-offset:2px;border-radius:4px}

  /* accessibility: respect reduced-motion preference */
  @media(prefers-reduced-motion:reduce){
    html{scroll-behavior:auto}
    *,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;
      transition-duration:.001ms!important;scroll-behavior:auto!important}
  }
  body{font-family:'Pretendard','Apple SD Gothic Neo',system-ui,sans-serif;background:#f6f7fb;
    color:var(--ink);line-height:1.78;-webkit-font-smoothing:antialiased;font-size:16.5px}
  a{color:var(--brand2)}
  .wrap{max-width:1120px;margin:0 auto;padding:0 22px}

  /* top utility bar */
  .util{background:#07090d;color:#aeb6c6;font-size:12.5px;letter-spacing:.2px}
  .util .wrap{display:flex;justify-content:space-between;align-items:center;height:36px;flex-wrap:wrap}
  .util a{color:#fff;font-weight:600}
  .util .l{color:#7c8496}
  .util .dot{display:inline-block;width:7px;height:7px;border-radius:50%;background:var(--ok);
    margin-right:6px;box-shadow:0 0 0 0 rgba(16,185,129,.6);animation:pulse 2s infinite}
  @keyframes pulse{0%{box-shadow:0 0 0 0 rgba(16,185,129,.5)}70%{box-shadow:0 0 0 8px rgba(16,185,129,0)}100%{box-shadow:0 0 0 0 rgba(16,185,129,0)}}

  header{background:rgba(9,11,16,.72);backdrop-filter:saturate(180%) blur(16px);
    border-bottom:1px solid rgba(255,255,255,.08);position:sticky;top:0;z-index:30}
  .nav{display:flex;align-items:center;justify-content:space-between;height:66px}
  .logo{display:flex;align-items:center;gap:11px;font-weight:800;font-size:19px;color:#fff;text-decoration:none;letter-spacing:-.4px}
  .logo .b{width:36px;height:36px;border-radius:11px;background:var(--grad);color:#fff;display:grid;place-items:center;font-weight:900;font-size:14px;box-shadow:0 6px 18px -6px rgba(255,45,85,.7)}
  .logo small{color:#8b93a6;font-weight:600;font-size:12px}
  .nav nav{display:flex;gap:26px;font-size:14.5px;font-weight:600}
  .nav nav a{color:#c3cad6;text-decoration:none;transition:color .2s}
  .nav nav a:hover{color:#fff}
  .cta-top{background:var(--grad);color:#fff!important;padding:10px 20px;border-radius:999px;font-weight:700;font-size:14px;text-decoration:none;box-shadow:0 8px 22px -8px rgba(255,45,85,.7);transition:transform .2s}
  .cta-top:hover{transform:translateY(-1px)}
  @media(max-width:860px){.nav nav{display:none}}

  /* hero (trendy dark gradient) */
  .hero{position:relative;background:radial-gradient(1200px 600px at 15% -10%,rgba(99,102,241,.35),transparent 55%),
    radial-gradient(900px 500px at 100% 0%,rgba(255,45,85,.28),transparent 50%),
    linear-gradient(180deg,#0b0d12,#11151f);
    color:#e8ecf4;padding:64px 0 120px;overflow:hidden}
  .hero::after{content:"";position:absolute;inset:0;background-image:radial-gradient(rgba(255,255,255,.05) 1px,transparent 1px);background-size:22px 22px;opacity:.5;pointer-events:none}
  .hero .wrap{position:relative;z-index:2}
  .crumb{font-size:13px;color:#8b93a6;margin-bottom:18px}
  .crumb a{color:#8b93a6;text-decoration:none}
  .pill{display:inline-flex;align-items:center;gap:8px;background:var(--glass);border:1px solid rgba(255,255,255,.14);
    color:#dfe4ee;font-size:13px;font-weight:600;padding:7px 15px;border-radius:999px;margin-bottom:20px;backdrop-filter:blur(8px)}
  .pill .dot{width:7px;height:7px;border-radius:50%;background:var(--ok);animation:pulse 2s infinite}
  .hero h1{font-size:clamp(30px,5vw,52px);font-weight:900;letter-spacing:-1.4px;line-height:1.2;color:#fff}
  .hero h1 em{font-style:normal;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
  .hero .dek{color:#aab2c2;font-size:clamp(15px,2vw,18px);margin-top:20px;max-width:720px}
  .hero .btns{margin-top:30px;display:flex;gap:12px;flex-wrap:wrap}
  .btn{display:inline-flex;align-items:center;gap:8px;padding:14px 26px;border-radius:999px;font-weight:700;font-size:15px;text-decoration:none;border:1px solid transparent;transition:transform .2s,box-shadow .2s}
  .btn-p{background:var(--grad);color:#fff;box-shadow:0 12px 30px -10px rgba(255,45,85,.7)}
  .btn-p:hover{transform:translateY(-2px)}
  .btn-o{border-color:rgba(255,255,255,.22);color:#e8ecf4;background:rgba(255,255,255,.04)}
  .btn-o:hover{border-color:#fff;background:rgba(255,255,255,.1)}

  /* floating stat cards over hero */
  .stats{position:relative;z-index:5;margin-top:-84px}
  .stats .wrap{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
  @media(max-width:760px){.stats .wrap{grid-template-columns:repeat(2,1fr)}}
  .stat{background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px 20px;box-shadow:var(--shadow)}
  .stat .n{font-size:clamp(24px,3vw,32px);font-weight:900;letter-spacing:-1px;
    background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
  .stat .t{color:var(--mut);font-size:13px;font-weight:600;margin-top:4px}

  /* layout: content + toc */
  .layout{display:grid;grid-template-columns:1fr 260px;gap:44px;padding:56px 0}
  @media(max-width:900px){.layout{grid-template-columns:1fr}}
  .toc{position:sticky;top:90px;align-self:start;font-size:14px;background:#fff;border:1px solid var(--line);
    border-radius:18px;padding:22px 20px;box-shadow:var(--shadow)}
  .toc h4{font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--mut);margin-bottom:14px;font-weight:700}
  .toc a{display:block;color:var(--sub);text-decoration:none;padding:7px 0 7px 14px;border-left:2px solid var(--line);transition:.2s}
  .toc a:hover{color:var(--brand);border-color:var(--brand);transform:translateX(2px)}
  @media(max-width:900px){.toc{display:none}}

  article h2{font-size:clamp(23px,3vw,31px);font-weight:900;letter-spacing:-.7px;margin:0 0 8px;
    padding-top:14px;scroll-margin-top:88px}
  article .lead2{color:var(--mut);margin-bottom:20px;font-size:15px}
  article h3{font-size:19px;font-weight:800;margin:28px 0 8px;letter-spacing:-.3px}
  article p{margin:0 0 15px;color:var(--sub)}
  article section{margin-bottom:56px}
  article strong{color:var(--ink)}
  article ul{margin:0 0 16px;padding-left:2px;list-style:none}
  article ul li{position:relative;padding:11px 0 11px 34px;border-bottom:1px solid var(--line2);color:var(--sub)}
  article ul li::before{content:"✓";position:absolute;left:2px;top:11px;width:20px;height:20px;border-radius:6px;
    background:rgba(16,185,129,.12);color:var(--ok);font-weight:800;font-size:12px;display:grid;place-items:center}
  article ul.warn li::before{content:"!";background:rgba(255,45,85,.12);color:var(--brand)}

  .card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:24px 26px;margin-bottom:16px;
    box-shadow:0 8px 24px -18px rgba(16,20,40,.3);transition:transform .2s,box-shadow .2s}
  .card:hover{transform:translateY(-3px);box-shadow:var(--shadow)}
  .card h3{margin-top:0;display:flex;align-items:center;gap:12px}
  .card h3 .step{flex:none;width:32px;height:32px;border-radius:10px;background:var(--grad2);color:#fff;
    display:grid;place-items:center;font-size:13px;font-weight:800}
  .callout{background:linear-gradient(135deg,#fff5f7,#fff);border:1px solid #ffd7de;border-left:4px solid var(--brand);border-radius:14px;
    padding:18px 22px;margin:0 0 20px;font-size:15px;color:var(--sub)}
  .callout b{color:var(--brand)}

  table{width:100%;border-collapse:separate;border-spacing:0;font-size:14.5px;margin:6px 0 20px;background:#fff;
    border:1px solid var(--line);border-radius:16px;overflow:hidden;box-shadow:0 8px 24px -18px rgba(16,20,40,.3)}
  th,td{text-align:left;padding:14px 18px;border-bottom:1px solid var(--line2)}
  th{background:#f5f6fb;font-weight:800;color:var(--ink);font-size:13.5px}
  tr:last-child td{border-bottom:none}
  td b{color:var(--ink)}

  /* keyword chips (region long-tail) */
  .chips{display:flex;flex-wrap:wrap;gap:9px;margin:4px 0 8px}
  .chips a{background:var(--chip);color:var(--sub);text-decoration:none;font-size:13.5px;font-weight:600;
    padding:8px 15px;border-radius:999px;border:1px solid var(--line);transition:.2s}
  .chips a:hover{background:var(--grad);color:#fff;border-color:transparent;transform:translateY(-1px)}

  details{border:1px solid var(--line);border-radius:14px;padding:16px 20px;margin-bottom:10px;background:#fff;transition:.2s}
  details[open]{box-shadow:var(--shadow)}
  summary{cursor:pointer;font-weight:700;font-size:16px;list-style:none;display:flex;justify-content:space-between;gap:12px;color:var(--ink)}
  summary::-webkit-details-marker{display:none}
  summary::after{content:'+';color:var(--brand);font-size:22px;font-weight:400;line-height:1}
  details[open] summary::after{content:'−'}
  details .a{color:var(--sub);margin-top:12px;font-size:15px}

  .band{position:relative;background:linear-gradient(135deg,#11151f,#1a1030);color:#fff;border-radius:24px;
    padding:52px 34px;text-align:center;margin:10px 0 0;overflow:hidden;box-shadow:var(--shadow)}
  .band::before{content:"";position:absolute;inset:0;background:radial-gradient(600px 300px at 50% -20%,rgba(255,45,85,.4),transparent 60%)}
  .band h2,.band p,.band a{position:relative;z-index:2}
  .band h2{color:#fff;font-size:clamp(23px,3vw,32px);font-weight:900;padding:0}
  .band p{color:#c1c8d6;max-width:560px;margin:14px auto 24px}

  footer{background:#0b0d12;border-top:1px solid rgba(255,255,255,.06);margin-top:64px;padding:52px 0 32px;font-size:14px;color:#8b93a6}
  .fgrid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:30px;margin-bottom:28px}
  @media(max-width:700px){.fgrid{grid-template-columns:1fr}}
  footer .logo{color:#fff}
  footer h4{color:#e8ecf4;font-size:14px;margin-bottom:12px}
  footer a{display:block;color:#8b93a6;text-decoration:none;padding:4px 0;transition:.2s}
  footer a:hover{color:var(--brand)}
  .fbot{border-top:1px solid rgba(255,255,255,.06);padding-top:20px;text-align:center;color:#6a7284;font-size:13px}
  .kw{color:#5a6274;font-size:12.5px;line-height:1.9;margin-top:8px}