:root{
      --bg:#f5f7fb;
      --surface:#ffffff;
      --text:#142033;
      --muted:#5b6b82;
      --border:#d9e3ef;
      --primary:#0f766e;
      --primary-dark:#115e59;
      --accent:#1d4ed8;
      --shadow-sm:0 8px 22px rgba(15,23,42,.06);
      --shadow-md:0 14px 36px rgba(15,23,42,.10);
      --radius:20px;
      --radius-lg:28px;
      --max:1180px;
      --grad-1:linear-gradient(135deg,#0f766e 0%,#14b8a6 100%);
    }

    *{
      box-sizing:border-box;
    }

    html{
      scroll-behavior:smooth;
    }

    body{
      margin:0;
      font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
      line-height:1.72;
      color:var(--text);
      background:
        radial-gradient(circle at top center,rgba(29,78,216,.05),transparent 28%),
        linear-gradient(180deg,#f7f9fc 0%,#f5f7fb 100%);
      overflow-x:hidden;
    }

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

    a:hover{
      text-decoration:underline;
    }

    .skip-link{
      position:absolute;
      left:-9999px;
      top:auto;
      width:1px;
      height:1px;
      overflow:hidden;
    }

    .skip-link:focus{
      left:12px;
      top:12px;
      width:auto;
      height:auto;
      padding:10px 12px;
      z-index:10000;
      background:#fff;
      color:#000;
      border-radius:10px;
      box-shadow:var(--shadow-md);
    }

    .header-container,
    .section-container{
      width:min(100% - 32px,var(--max));
      margin-inline:auto;
    }

    header{
      position:sticky;
      top:0;
      z-index:999;
      background:rgba(255,255,255,.92);
      backdrop-filter:blur(12px) saturate(1.15);
      border-bottom:1px solid rgba(217,227,239,.88);
      box-shadow:0 6px 18px rgba(15,23,42,.04);
    }

    .header-container{
      display:flex;
      align-items:center;
      justify-content:space-between;
      gap:18px;
      padding:14px 0;
    }

    .logo-area{
      display:flex;
      align-items:center;
      gap:14px;
      color:var(--text);
      text-decoration:none;
    }

    .logo-title{
      display:block;
      margin:0;
      font-size:1.08rem;
      font-weight:850;
      line-height:1.2;
      color:var(--text);
    }

    .logo-text p{
      margin:3px 0 0;
      color:var(--muted);
      font-size:.94rem;
      line-height:1.25;
    }

    nav{
      display:flex;
      flex-wrap:wrap;
      gap:8px;
      justify-content:flex-end;
    }

    nav a{
      color:var(--text);
      font-weight:650;
      font-size:.94rem;
      white-space:nowrap;
      padding:8px 10px;
      border-radius:10px;
    }

    nav a:hover{
      background:#eef5fb;
      color:var(--primary);
      text-decoration:none;
    }

    .section-hero,
    .section-block{
      padding:58px 0;
    }

    .hero-card,
    .content-card{
      background:linear-gradient(180deg,#ffffff 0%,#fbfdff 100%);
      border:1px solid rgba(217,227,239,.95);
      border-radius:var(--radius-lg);
      box-shadow:var(--shadow-md);
      padding:32px;
    }

    .hero-line{
      width:92px;
      height:7px;
      border-radius:999px;
      background:linear-gradient(90deg,var(--primary),var(--accent));
      margin-bottom:18px;
    }

    h1{
      margin:0 0 14px;
      font-size:clamp(2rem,4.6vw,3.35rem);
      line-height:1.08;
      letter-spacing:-.035em;
      color:#0b1324;
    }

    h2{
      margin:34px 0 12px;
      font-size:clamp(1.35rem,2.4vw,2rem);
      line-height:1.18;
      color:#0b1324;
      letter-spacing:-.02em;
    }

    h3{
      margin:24px 0 10px;
      font-size:1.18rem;
      color:#0b1324;
    }

    p{
      color:var(--muted);
      margin:0 0 14px;
    }

    ul{
      color:var(--muted);
      margin:0 0 16px;
      padding-left:22px;
    }

    li{
      margin-bottom:8px;
    }

    .lead{
      font-size:1.08rem;
      max-width:980px;
    }

    .notice{
      margin:22px 0;
      padding:18px;
      border-radius:18px;
      background:#fff7ed;
      border:1px solid #fed7aa;
      color:#7c2d12;
      box-shadow:var(--shadow-sm);
    }

    .notice p,
    .notice strong{
      color:#7c2d12;
    }

    .important{
      margin:22px 0;
      padding:18px;
      border-radius:18px;
      background:#fef2f2;
      border:1px solid #fecaca;
      color:#7f1d1d;
    }

    .important p,
    .important strong{
      color:#7f1d1d;
    }

    .toc{
      margin:24px 0;
      padding:18px;
      border:1px solid var(--border);
      border-radius:var(--radius);
      background:#f8fbff;
    }

    .toc strong{
      display:block;
      margin-bottom:8px;
      color:#0b1324;
    }

    .toc ul{
      margin:0;
      columns:2;
    }

    .meta-box{
      margin-top:18px;
      padding:16px;
      border-radius:18px;
      background:#f8fbff;
      border:1px solid var(--border);
    }

    .cta-row{
      display:flex;
      flex-wrap:wrap;
      gap:10px;
      margin-top:24px;
    }

    .cta-button{
      display:inline-flex;
      align-items:center;
      justify-content:center;
      min-height:50px;
      padding:0 20px;
      border-radius:16px;
      background:var(--grad-1);
      color:#fff;
      font-weight:850;
      text-decoration:none;
      box-shadow:0 16px 28px rgba(15,118,110,.22);
    }

    .cta-button:hover{
      color:#fff;
      text-decoration:none;
      transform:translateY(-2px);
    }

    footer{
      padding:40px 16px 44px;
      background:linear-gradient(180deg,#eef4f8 0%,#eaf1f6 100%);
      border-top:1px solid var(--border);
      text-align:center;
      color:var(--muted);
    }

    footer p{
      max-width:980px;
      margin:0 auto;
    }

    @media(max-width:760px){
      .header-container{
        align-items:flex-start;
        flex-direction:column;
      }

      nav{
        justify-content:flex-start;
      }

      .hero-card,
      .content-card{
        padding:22px;
      }

      .toc ul{
        columns:1;
      }

      .cta-button{
        width:100%;
      }
    }