:root{
  --bg:#f4f8fa; --card:#ffffff; --ink:#15303a; --muted:#5d7682;
  --brand:#0e7c86; --brand2:#16a3b0; --accent:#f0a500; --line:#e1edf1;
  --tip:#0e7c86; --warn:#c77700; --info:#2563a8; --danger:#c0392b;
  --shadow:0 6px 22px rgba(16,60,72,.10);
  --radius:14px;
}
*{box-sizing:border-box}
body{margin:0;font:16px/1.7 -apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}
.muted{color:var(--muted)}

/* ---------- header ---------- */
.site-head{background:linear-gradient(120deg,var(--brand),var(--brand2));color:#fff;
  position:sticky;top:0;z-index:20;box-shadow:0 2px 10px rgba(0,0,0,.08)}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;padding:13px 20px}
.brand{font-weight:800;font-size:21px;color:#fff;letter-spacing:.3px}
.brand:hover{text-decoration:none}
.topnav a{color:#eaffff;margin-left:18px;font-size:14px;font-weight:600;opacity:.92}
.topnav a:hover{opacity:1;text-decoration:none}
.crumb{padding:14px 20px;color:var(--muted);font-size:13px}
.crumb a{color:var(--muted)}
.crumb a:hover{color:var(--brand)}

/* ---------- article ---------- */
.article{max-width:820px;padding-top:8px;padding-bottom:48px}
.article-head{margin:10px 0 4px}
.article-head h1{font-size:34px;line-height:1.18;margin:0 0 6px;letter-spacing:-.2px}
.byline{color:var(--muted);font-size:14px;margin:0}
.share{display:flex;align-items:center;gap:8px;margin:12px 0 2px;flex-wrap:wrap}
.share-label{font-size:13px;font-weight:700;color:var(--muted);margin-right:2px}
.share-btn{display:inline-flex;align-items:center;justify-content:center;width:34px;height:34px;border-radius:50%;
  background:#fff;border:1px solid var(--line);color:var(--muted);transition:.15s;padding:0;cursor:pointer}
.share-btn:hover{text-decoration:none;transform:translateY(-1px);box-shadow:var(--shadow);color:#fff}
.share-btn svg{width:17px;height:17px;fill:currentColor}
.share-btn.x:hover{background:#000;border-color:#000}
.share-btn.fb:hover{background:#1877f2;border-color:#1877f2}
.share-btn.pin:hover{background:#bd081c;border-color:#bd081c}
.share-btn.rd:hover{background:#ff4500;border-color:#ff4500}
.share-btn.copy:hover{background:var(--brand);border-color:var(--brand);color:#fff}
.share-btn.copied{background:var(--brand);border-color:var(--brand);color:#fff}
.share-btn.copied svg{fill:#fff}
.hero-fig{margin:18px 0 6px;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.hero-fig img{width:100%;height:auto;aspect-ratio:16/9;object-fit:cover;max-height:440px}
.answer-nugget{background:linear-gradient(180deg,#e7f7f9,#e0f3f6);border-left:4px solid var(--brand2);
  padding:14px 18px;border-radius:0 12px 12px 0;margin:20px 0;font-size:15.5px}
.answer-nugget .an-label{display:inline-block;font-size:11px;font-weight:800;letter-spacing:.08em;
  text-transform:uppercase;color:var(--brand);background:#fff;padding:2px 8px;border-radius:20px;margin-right:8px}
.article-body{margin-top:8px}
.article-body h2{font-size:23px;margin:34px 0 8px;color:var(--brand);
  padding-bottom:7px;border-bottom:2px solid var(--line)}
.article-body p{margin:12px 0}
.article-body ul,.article-body ol{margin:12px 0;padding-left:22px}
.article-body li{margin:6px 0}
.article-body figure{margin:22px 0}
.article-body figure img{border-radius:12px;box-shadow:var(--shadow);width:100%}
.article-body figcaption{font-size:13px;color:var(--muted);margin-top:8px;text-align:center}
.data-table{width:100%;border-collapse:collapse;margin:20px 0;background:var(--card);
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.data-table th,.data-table td{border-top:1px solid var(--line);padding:10px 14px;font-size:14px;text-align:left;vertical-align:top}
.data-table thead th{background:#eaf6f8;color:var(--brand);font-weight:800}

/* care glance */
.care-glance{width:100%;border-collapse:collapse;margin:20px 0;background:var(--card);
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.care-glance caption{font-weight:800;padding:11px 16px;background:#eaf6f8;text-align:left;color:var(--brand)}
.care-glance th,.care-glance td{text-align:left;padding:9px 16px;border-top:1px solid var(--line);font-size:14.5px}
.care-glance th{width:36%;color:var(--muted);font-weight:600;background:#fafdfe}

/* callouts */
.callout{border-radius:12px;padding:6px 16px 12px;margin:18px 0;border-left:5px solid var(--tip);
  background:#eef9fb}
.callout .callout-h{font-weight:800;margin:10px 0 2px;color:var(--tip);font-size:14px;
  text-transform:uppercase;letter-spacing:.04em}
.callout p{margin:4px 0}
.callout.warning{border-color:var(--warn);background:#fdf4e6}
.callout.warning .callout-h{color:var(--warn)}
.callout.info{border-color:var(--info);background:#eaf2fb}
.callout.info .callout-h{color:var(--info)}
.callout.danger{border-color:var(--danger);background:#fdecea}
.callout.danger .callout-h{color:var(--danger)}

/* TOC */
.toc{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:14px 20px;margin:22px 0;box-shadow:var(--shadow)}
.toc-h{font-weight:800;color:var(--brand);margin:0 0 6px;font-size:14px;text-transform:uppercase;letter-spacing:.05em}
.toc ol{margin:0;padding-left:20px}
.toc li{margin:5px 0}
.toc a{color:var(--ink)}

/* sources */
.cites{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:8px 20px 14px;margin:30px 0;box-shadow:var(--shadow)}
.cites h2{margin-top:14px;color:var(--brand)}
.cites ul{margin:6px 0 8px;padding-left:20px}
.cites a{font-weight:600}

/* FAQ */
.faq{margin:30px 0}
.faq h2{color:var(--brand);font-size:23px;margin:0 0 10px}
.faq-item{background:var(--card);border:1px solid var(--line);border-radius:12px;margin:10px 0;
  overflow:hidden;box-shadow:var(--shadow)}
.faq-item summary{cursor:pointer;padding:14px 18px;font-weight:700;list-style:none;
  display:flex;justify-content:space-between;align-items:center;gap:10px}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";font-size:20px;color:var(--brand);font-weight:800}
.faq-item[open] summary::after{content:"\2013"}
.faq-a{padding:0 18px 16px;color:var(--ink)}

/* related */
.related{margin:32px 0}
.related h2{font-size:22px;color:var(--brand);margin:0 0 14px}
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.rel-card{background:var(--card);border:1px solid var(--line);border-radius:12px;overflow:hidden;
  box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s}
.rel-card:hover{transform:translateY(-3px);box-shadow:0 10px 26px rgba(16,60,72,.16);text-decoration:none}
.rel-card img{width:100%;height:130px;object-fit:cover}
.rel-card div{padding:10px 14px 14px}
.rel-card h4{margin:0 0 6px;font-size:15.5px;color:var(--ink)}

/* author */
.author-box{display:flex;gap:14px;background:linear-gradient(120deg,#eaf6f8,#f3fbfc);
  border-radius:var(--radius);padding:16px 18px;margin:30px 0}
.author-box .avatar{width:48px;height:48px;border-radius:50%;background:var(--brand);color:#fff;
  display:flex;align-items:center;justify-content:center;font-weight:800;font-size:20px;flex:none}
.author-box strong{font-size:15.5px}
.author-box .role{color:var(--brand);font-size:13px;font-weight:600}
.author-box .bio{margin:4px 0 0;font-size:13.5px;color:var(--muted)}
.verified{font-size:13px;color:var(--muted);border-top:1px dashed var(--line);padding-top:10px}

/* newsletter */
.newsletter{background:linear-gradient(120deg,var(--brand),var(--brand2));color:#fff;
  border-radius:var(--radius);padding:26px 28px;margin:34px 0;text-align:center;box-shadow:var(--shadow)}
.newsletter h3{margin:0 0 6px;color:#fff;font-size:21px}
.newsletter p{margin:0 auto 14px;max-width:560px;color:#eafdff}
.nl-form{display:flex;gap:10px;justify-content:center;flex-wrap:wrap}
.nl-form input{flex:1;min-width:220px;max-width:340px;padding:12px 14px;border:0;border-radius:10px;font-size:15px}
.nl-form button{background:var(--accent);color:#15303a;border:0;border-radius:10px;
  padding:12px 22px;font-weight:800;font-size:15px;cursor:pointer}
.nl-form button:hover{filter:brightness(1.05)}
.nl-fine{font-size:12.5px;color:#cdeff2;margin:10px 0 0}

/* tags */
.tag{display:inline-block;background:#eaf6f8;color:var(--brand);font-size:11px;
  padding:2px 9px;border-radius:20px;margin-left:6px;font-weight:700}

/* ---------- category hub ---------- */
.cat-hero{position:relative;color:#fff;padding:54px 20px;background-size:cover;background-position:center;
  background-color:var(--brand)}
.cat-hero::after{content:"";position:absolute;inset:0;background:linear-gradient(120deg,rgba(8,52,58,.82),rgba(14,124,134,.6))}
.cat-hero-in{position:relative;z-index:1;max-width:1080px;margin:0 auto}
.cat-hero h1{color:#fff;font-size:34px;margin:0 0 8px}
.cat-hero p{max-width:680px;margin:0;color:#eafdff;font-size:16px}
.hub-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:28px 0}
.hub-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s}
.hub-card:hover{transform:translateY(-3px);box-shadow:0 12px 28px rgba(16,60,72,.16);text-decoration:none}
.hub-card img{width:100%;height:160px;object-fit:cover}
.hub-body{padding:12px 16px 18px}
.hub-body h3{margin:0 0 6px;font-size:17px;color:var(--ink)}

/* ---------- homepage ---------- */
.hero{position:relative;color:#fff;padding:78px 20px;background-size:cover;background-position:center;
  background-color:var(--brand)}
.hero::after{content:"";position:absolute;inset:0;background:linear-gradient(120deg,rgba(7,46,52,.85),rgba(14,124,134,.55))}
.hero-in{position:relative;z-index:1}
.hero h1{color:#fff;font-size:42px;line-height:1.12;margin:0 0 12px;max-width:760px}
.hero p{color:#eafdff;font-size:18px;max-width:680px;margin:0 0 22px}
.hero .cta{display:inline-block;background:var(--accent);color:#15303a;font-weight:800;
  padding:13px 26px;border-radius:12px;font-size:16px}
.hero .cta:hover{filter:brightness(1.05);text-decoration:none}
.sec-h{font-size:25px;color:var(--ink);margin:42px 0 16px}
.cat-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}
.cat-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s}
.cat-card:hover{transform:translateY(-3px);box-shadow:0 12px 28px rgba(16,60,72,.16);text-decoration:none}
.cat-card img{width:100%;height:150px;object-fit:cover}
.cat-body{padding:14px 18px 18px}
.cat-card h3{margin:0 0 6px;font-size:19px;color:var(--brand)}
.cat-card p{margin:0;color:var(--muted);font-size:14.5px}
.post-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.post-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s}
.post-card:hover{transform:translateY(-3px);box-shadow:0 12px 28px rgba(16,60,72,.16);text-decoration:none}
.post-card img{width:100%;height:170px;object-fit:cover}
.pc-body{padding:12px 16px 18px}
.pc-cat{display:inline-block;font-size:11px;font-weight:800;letter-spacing:.04em;text-transform:uppercase;
  color:var(--brand);background:#eaf6f8;padding:2px 9px;border-radius:20px}
.post-card h3{margin:8px 0 6px;font-size:17px;color:var(--ink);line-height:1.3}
.post-card p{margin:0;color:var(--muted);font-size:14px}

/* ---------- footer ---------- */
.site-foot{background:#0c2a32;color:#cfe7ec;margin-top:46px;padding:30px 0 22px;font-size:13.5px}
.foot-grid{max-width:1080px;margin:0 auto;padding:0 20px;display:flex;justify-content:space-between;
  gap:20px;flex-wrap:wrap;align-items:flex-start}
.foot-grid .brand{color:#fff;font-size:19px}
.foot-nav a{display:inline-block;color:#9fe3ea;margin-left:18px;font-size:14px}
.foot-nav a:first-child{margin-left:0}
.copy{max-width:1080px;margin:18px auto 0;padding:14px 20px 0;border-top:1px solid rgba(255,255,255,.12);color:#9bb9c0}

/* ---------- responsive ---------- */
@media(max-width:880px){
  .rel-grid,.hub-grid,.post-grid{grid-template-columns:repeat(2,1fr)}
  .hero h1{font-size:34px}
}
@media(max-width:560px){
  .cat-grid,.rel-grid,.hub-grid,.post-grid{grid-template-columns:1fr}
  .topnav a{margin-left:12px;font-size:13px}
  .article-head h1{font-size:28px}
  .hero{padding:56px 18px}
}