:root{
  --ink:#0f1729; --body:#3c4658; --muted:#6b7384;
  --line:#e6e9ef; --bg:#ffffff; --bg-soft:#f6f8fb;
  --accent:#2f5bea; --accent-dark:#1e40c4; --accent-soft:#eaf0ff;
  --radius:14px; --shadow:0 1px 2px rgba(16,23,41,.05),0 8px 24px rgba(16,23,41,.06);
  --maxw:1120px;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  color:var(--body);background:var(--bg);line-height:1.65;font-size:17px;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4{color:var(--ink);line-height:1.2;font-weight:700;margin:0 0 .5em}
h1{font-size:clamp(2rem,4.5vw,3.1rem);letter-spacing:-.02em}
h2{font-size:clamp(1.5rem,3vw,2.1rem);letter-spacing:-.01em}
h3{font-size:1.2rem}
p{margin:0 0 1rem}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.skip-link{position:absolute;left:-9999px}
.skip-link:focus{left:8px;top:8px;background:#fff;padding:8px;z-index:100;border-radius:8px}

/* Buttons */
.btn{display:inline-block;padding:.8rem 1.5rem;border-radius:10px;font-weight:600;
  font-size:1rem;cursor:pointer;border:1px solid transparent;transition:.15s;text-decoration:none}
.btn-primary{background:var(--accent);color:#fff}
.btn-primary:hover{background:var(--accent-dark);text-decoration:none}
.btn-ghost{background:#fff;color:var(--ink);border-color:var(--line)}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent);text-decoration:none}

/* Header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.9);
  backdrop-filter:saturate(180%) blur(10px);border-bottom:1px solid var(--line)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo{font-weight:700;font-size:1.2rem;color:var(--ink);text-decoration:none;letter-spacing:-.02em}
.logo-dot{color:var(--accent)}
.site-nav ul{display:flex;gap:4px;list-style:none;margin:0;padding:0}
.site-nav a{color:var(--body);font-weight:500;font-size:.97rem;padding:.5rem .8rem;border-radius:8px;text-decoration:none}
.site-nav a:hover{background:var(--bg-soft);color:var(--ink)}
.site-nav a[aria-current=page]{color:var(--accent);background:var(--accent-soft)}
.nav-toggle{display:none;background:none;border:0;font-size:1.5rem;cursor:pointer;color:var(--ink)}

/* Hero */
.hero{padding:5rem 0 4rem;background:linear-gradient(180deg,var(--accent-soft),#fff)}
.hero .eyebrow{color:var(--accent);font-weight:600;text-transform:uppercase;letter-spacing:.08em;font-size:.85rem}
.hero p.lead{font-size:1.2rem;max-width:620px;margin:1rem 0 2rem}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap}

/* Sections */
.section{padding:4rem 0}
.section.soft{background:var(--bg-soft)}
.section-head{max-width:680px;margin-bottom:2.5rem}
.section-head p{color:var(--muted);font-size:1.1rem}
.lead{font-size:1.15rem}

/* Grid cards */
.grid{display:grid;gap:1.5rem}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.6rem;transition:.15s}
.card:hover{box-shadow:var(--shadow);border-color:#d6dbe6;transform:translateY(-2px)}
.card h3{margin-bottom:.4rem}
.card p{color:var(--muted);font-size:.97rem;margin-bottom:0}
.card .card-link{display:inline-block;margin-top:1rem;font-weight:600}
.card-icon{width:44px;height:44px;border-radius:10px;background:var(--accent-soft);
  display:flex;align-items:center;justify-content:center;font-size:1.3rem;margin-bottom:1rem}

/* Article content */
.prose{max-width:760px}
.prose h2{margin-top:2.2rem}
.prose h3{margin-top:1.6rem}
.prose img{border-radius:10px;margin:1.5rem 0}
.prose ul,.prose ol{padding-left:1.3rem}
.prose blockquote{border-left:3px solid var(--accent);padding-left:1.2rem;color:var(--muted);font-style:italic;margin:1.5rem 0}

/* Article list */
.post-list{display:grid;gap:1.3rem;grid-template-columns:repeat(3,1fr)}
.post-card{display:flex;flex-direction:column;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:#fff;transition:.15s}
.post-card:hover{box-shadow:var(--shadow);transform:translateY(-2px)}
.post-card .thumb{aspect-ratio:16/9;background:var(--bg-soft);object-fit:cover;width:100%}
.post-card .pc-body{padding:1.2rem}
.post-card h3{font-size:1.05rem;margin-bottom:.3rem}
.post-card .meta{color:var(--muted);font-size:.82rem}

/* Meta / breadcrumb */
.breadcrumb{font-size:.85rem;color:var(--muted);padding:1.2rem 0}
.breadcrumb a{color:var(--muted)}
.article-meta{color:var(--muted);font-size:.9rem;margin-bottom:1.5rem}

/* CTA band */
.cta-band{background:var(--ink);color:#fff;border-radius:var(--radius);padding:3rem;text-align:center;margin:3rem 0}
.cta-band h2{color:#fff}
.cta-band p{color:#c3cadb;max-width:560px;margin:0 auto 1.5rem}

/* Footer */
.site-footer{background:var(--bg-soft);border-top:1px solid var(--line);margin-top:4rem;padding:3rem 0 1.5rem}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:2rem}
.footer-brand p{color:var(--muted);font-size:.92rem;max-width:320px;margin-top:.6rem}
.footer-col h2{font-size:.8rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin-bottom:.8rem}
.footer-col ul{list-style:none;margin:0;padding:0;display:grid;gap:.5rem}
.footer-col a{color:var(--body);font-size:.94rem}
.footer-bottom{border-top:1px solid var(--line);margin-top:2rem;padding-top:1.2rem;color:var(--muted);font-size:.85rem}

/* Tools */
.tool-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1.3rem}
.tool-box{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.8rem;box-shadow:var(--shadow)}
.field{margin-bottom:1.1rem}
.field label{display:block;font-weight:600;color:var(--ink);margin-bottom:.4rem;font-size:.92rem}
.field input,.field textarea,.field select{width:100%;padding:.7rem .9rem;border:1px solid var(--line);
  border-radius:9px;font:inherit;font-size:.97rem;background:#fff}
.field input:focus,.field textarea:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}
.result-box{background:var(--bg-soft);border:1px solid var(--line);border-radius:9px;padding:1rem;font-family:ui-monospace,Menlo,Consolas,monospace;font-size:.88rem;white-space:pre-wrap;word-break:break-word}

/* SERP preview */
.serp{border:1px solid var(--line);border-radius:9px;padding:1rem 1.2rem;max-width:600px;background:#fff}
.serp .s-url{color:#202124;font-size:.82rem}
.serp .s-title{color:#1a0dab;font-size:1.25rem;margin:.1rem 0;line-height:1.3}
.serp .s-desc{color:#4d5156;font-size:.88rem}

.counter{font-size:.82rem;color:var(--muted)}
.counter.over{color:#c0392b;font-weight:600}
.counter.ok{color:#1a7f37}

/* Responsive */
@media(max-width:860px){
  .grid-3,.tool-grid,.post-list{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:640px){
  .nav-toggle{display:block}
  .site-nav{position:absolute;top:68px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);display:none}
  .site-nav.open{display:block}
  .site-nav ul{flex-direction:column;padding:12px}
  .grid-3,.grid-2,.tool-grid,.post-list,.footer-grid{grid-template-columns:1fr}
  .cta-band{padding:2rem 1.2rem}
}