:root{
  --pd-ink:#16202e;
  --pd-ink-2:#3a4757;
  --pd-muted:#6b7888;
  --pd-line:#e3e9f1;
  --pd-bg:#f5f8fc;
  --pd-card:#ffffff;
  --pd-primary:#0b3d8f;
  --pd-primary-2:#0a59c4;
  --pd-accent:#00b3d6;
  --pd-accent-2:#ff9d2e;
  --pd-shadow:0 10px 30px rgba(13,38,76,.08);
  --pd-radius:14px;
  --h2-inset:0px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  color:var(--pd-ink);background:var(--pd-bg);line-height:1.75;-webkit-font-smoothing:antialiased;
}
a{color:var(--pd-primary-2);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%}

/* ---------- Header ---------- */
.pd-header{position:sticky;top:0;z-index:50;background:linear-gradient(120deg,#0a2540,#0b3d8f 55%,#0a59c4);box-shadow:0 2px 18px rgba(10,37,64,.25)}
.pd-header-inner{max-width:1180px;margin:0 auto;padding:0 24px;height:64px;display:flex;align-items:center;gap:24px}
.pd-logo{color:#fff;font-weight:800;font-size:19px;letter-spacing:.5px;white-space:nowrap}
.pd-nav{display:flex;align-items:center;gap:4px;margin-left:auto}
.pd-nav>a,.pd-has-sub>a{color:#dbe7fb;padding:8px 12px;border-radius:8px;font-size:15px;display:block}
.pd-nav>a:hover,.pd-has-sub>a:hover{background:rgba(255,255,255,.12);text-decoration:none;color:#fff}
.pd-has-sub{position:relative}
.pd-sub{display:none;position:absolute;top:100%;left:0;min-width:150px;background:#fff;border-radius:10px;box-shadow:var(--pd-shadow);padding:8px;z-index:60}
.pd-sub a{display:block;color:var(--pd-ink);padding:8px 10px;border-radius:8px;font-size:14px;white-space:nowrap}
.pd-sub a:hover{background:var(--pd-bg);color:var(--pd-primary)}
.pd-has-sub:hover .pd-sub{display:block}
.pd-nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px;margin-left:auto}
.pd-nav-toggle span{width:24px;height:2px;background:#fff;border-radius:2px}

/* ---------- Floating capsule ---------- */
.pd-capsule{position:fixed;right:22px;top:50%;transform:translateY(-50%);z-index:45;display:flex;flex-direction:column;gap:12px}
.pd-cap-btn{width:50px;height:50px;border:0;border-radius:25px;cursor:pointer;font-size:18px;font-weight:700;color:#fff;
  background:linear-gradient(135deg,var(--pd-accent),var(--pd-primary-2));box-shadow:0 8px 22px rgba(0,179,214,.45);transition:transform .15s}
.pd-cap-btn:hover{transform:scale(1.06)}
.pd-cap-wx{background:linear-gradient(135deg,var(--pd-accent-2),#ff7a00);box-shadow:0 8px 22px rgba(255,157,46,.45)}

/* ---------- Modal ---------- */
.pd-modal{display:none;position:fixed;inset:0;background:rgba(8,18,34,.6);z-index:80;align-items:center;justify-content:center}
.pd-modal.open{display:flex}
.pd-modal-inner{position:relative;background:#fff;border-radius:10px;padding:10px;box-shadow:0 20px 60px rgba(0,0,0,.4)}
.pd-modal-inner img{display:block;border-radius:6px;width:300px;height:500px;object-fit:contain}
.pd-modal-close{position:absolute;top:-14px;right:-14px;width:34px;height:34px;border-radius:50%;border:0;background:#fff;color:#16202e;font-size:20px;cursor:pointer;box-shadow:var(--pd-shadow)}

/* ---------- Layout ---------- */
.pd-wrap{max-width:1180px;margin:0 auto;padding:0 24px}
.pd-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:48px;align-items:start;padding:18px 0 60px}
.pd-main{min-width:0;padding-left:var(--h2-inset)}
.pd-aside{position:sticky;top:84px;align-self:start}

/* ---------- Breadcrumb ---------- */
.pd-wrap>nav[aria-label="breadcrumb"]{padding:16px 0 0}
ol.crumbs{list-style:none;display:flex;flex-wrap:wrap;gap:6px;margin:0;padding:0;font-size:13px;color:var(--pd-muted)}
ol.crumbs li{display:flex;align-items:center}
ol.crumbs li:not(:last-child)::after{content:"›";margin-left:6px;color:#b6c2d2}
ol.crumbs a{color:var(--pd-muted)}
ol.crumbs a:hover{color:var(--pd-primary)}
ol.crumbs li[aria-current]{color:var(--pd-ink);font-weight:600}

/* ---------- Article / Content ---------- */
.pd-h1{font-size:30px;line-height:1.3;margin:8px 0 10px;color:var(--pd-ink);font-weight:800}
.pd-meta{display:flex;flex-wrap:wrap;gap:14px;font-size:13px;color:var(--pd-muted);margin-bottom:18px;
  border-bottom:1px dashed var(--pd-line);padding-bottom:12px}
.pd-content{max-width:780px}
.pd-content h2{font-size:22px;margin:34px 0 12px;padding-left:12px;border-left:4px solid var(--pd-primary);color:var(--pd-ink);scroll-margin-top:84px}
.pd-content h3{font-size:18px;margin:24px 0 10px;color:var(--pd-primary);scroll-margin-top:84px}
.pd-content h4{font-size:16px;margin:18px 0 8px;color:var(--pd-ink-2)}
.pd-content p{margin:12px 0}
.pd-content ul{margin:12px 0;padding-left:22px}
.pd-content li{margin:6px 0}
.pd-content code{background:#eef3fb;color:#0a59c4;padding:1px 6px;border-radius:5px;font-size:14px}

table.data{border-collapse:collapse;width:100%;margin:16px 0;font-size:14px;background:#fff;box-shadow:var(--pd-shadow);border-radius:10px;overflow:hidden}
table.data th{background:var(--pd-primary);color:#fff;text-align:left;padding:10px 12px;font-weight:600}
table.data td{padding:9px 12px;border-top:1px solid var(--pd-line)}
table.data tr:nth-child(even) td{background:#f7fafd}

blockquote.callout{border-radius:10px;padding:14px 16px;margin:16px 0;font-size:15px;line-height:1.7}
.callout-summary{background:#eaf3ff;border-left:4px solid var(--pd-primary-2)}
.callout-conclusion{background:#fff4e6;border-left:4px solid var(--pd-accent-2);font-weight:600}
.callout-case{background:#eefbf3;border-left:4px solid #1f9d55}

/* FAQ */
.faq{margin:28px 0}
.faq h2{font-size:20px;color:var(--pd-primary);border-left:4px solid var(--pd-accent)}
.faq details{border:1px solid var(--pd-line);border-radius:10px;margin:10px 0;background:#fff;overflow:hidden}
.faq summary{cursor:pointer;padding:13px 16px;font-weight:600;color:var(--pd-ink);list-style:none;position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:16px;top:50%;transform:translateY(-50%);color:var(--pd-primary);font-size:20px}
.faq details[open] summary::after{content:"−"}
.faq details p{margin:0;padding:0 16px 14px;color:var(--pd-ink-2)}

/* TOC */
.pd-toc{background:#fff;border:1px solid var(--pd-line);border-radius:12px;padding:16px;box-shadow:var(--pd-shadow);max-height:calc(100vh - 110px);overflow:auto}
.pd-toc-title{font-weight:700;font-size:14px;color:var(--pd-ink);margin-bottom:10px}
.pd-toc ul{list-style:none;margin:0;padding:0}
.pd-toc li{margin:7px 0;font-size:13px;line-height:1.5}
.pd-toc a{color:var(--pd-ink-2)}
.pd-toc a:hover{color:var(--pd-primary)}

/* ---------- List / Cards ---------- */
.pd-list .pd-list-desc{color:var(--pd-muted);margin:6px 0 22px}
.pd-itemlist{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}
.pd-card{display:block;background:var(--pd-card);border:1px solid var(--pd-line);border-radius:var(--pd-radius);padding:18px 20px;box-shadow:var(--pd-shadow);transition:transform .15s,border-color .15s}
.pd-card:hover{transform:translateY(-3px);border-color:var(--pd-primary-2);text-decoration:none}
.pd-card-cat{display:inline-block;font-size:12px;color:var(--pd-primary-2);background:#eaf3ff;padding:2px 10px;border-radius:20px;margin-bottom:10px}
.pd-card h3{margin:0 0 8px;font-size:17px;color:var(--pd-ink)}
.pd-card p{margin:0;font-size:14px;color:var(--pd-muted);line-height:1.6}

.pd-cat-side{background:#fff;border:1px solid var(--pd-line);border-radius:12px;padding:16px;box-shadow:var(--pd-shadow)}
.pd-cat-title{font-weight:700;font-size:14px;margin-bottom:10px;color:var(--pd-ink)}
ul.category-list{list-style:none;margin:0;padding:0}
ul.category-list li{margin:2px 0}
ul.category-list a{display:block;padding:9px 12px;border-radius:8px;color:var(--pd-ink-2);font-size:14px}
ul.category-list a:hover{background:var(--pd-bg);color:var(--pd-primary);text-decoration:none}
ul.category-list li.active a{background:var(--pd-primary);color:#fff}

/* ---------- Home ---------- */
.pd-hero{background:linear-gradient(135deg,#0a2540,#0b3d8f 60%,#0a59c4);color:#fff;border-radius:0 0 28px 28px;padding:56px 0 48px;margin-bottom:8px}
.pd-hero-inner{max-width:1180px;margin:0 auto;padding:0 24px}
.pd-hero-kicker{font-size:14px;letter-spacing:2px;color:#8fd0ff;text-transform:uppercase;margin-bottom:14px}
.pd-hero-title{font-size:40px;line-height:1.25;margin:0 0 16px;font-weight:800}
.pd-hero-sub{font-size:17px;color:#cfe0f5;max-width:760px;margin:0 0 26px}
.pd-hero-cta{display:flex;flex-wrap:wrap;gap:14px;margin-bottom:30px}
.pd-btn{display:inline-block;background:var(--pd-accent);color:#04222b;font-weight:700;padding:12px 22px;border-radius:30px;font-size:15px}
.pd-btn:hover{text-decoration:none;filter:brightness(1.05)}
.pd-btn-ghost{background:transparent;border:1.5px solid rgba(255,255,255,.6);color:#fff}
.pd-hero-stats{display:flex;flex-wrap:wrap;gap:34px;list-style:none;margin:0;padding:0}
.pd-hero-stats li{display:flex;flex-direction:column}
.pd-hero-stats b{font-size:26px;color:#fff}
.pd-hero-stats span{font-size:13px;color:#9fc1e6}

.pd-section{max-width:1180px;margin:0 auto;padding:40px 24px 0}
.pd-sec-title{font-size:24px;color:var(--pd-ink);margin:0 0 20px;font-weight:800;position:relative;padding-left:14px}
.pd-sec-title::before{content:"";position:absolute;left:0;top:6px;bottom:6px;width:5px;border-radius:3px;background:var(--pd-accent)}
.pd-pillrow{display:flex;flex-wrap:wrap;gap:12px}
.pd-pill{display:inline-block;background:#fff;border:1px solid var(--pd-line);color:var(--pd-primary);padding:10px 18px;border-radius:30px;font-weight:600;box-shadow:var(--pd-shadow)}
.pd-pill:hover{text-decoration:none;border-color:var(--pd-primary-2);background:#eaf3ff}
.pd-more{margin-top:18px;font-weight:600}
.pd-band{background:#fff;border:1px solid var(--pd-line);border-radius:18px;box-shadow:var(--pd-shadow);margin-top:36px}
.pd-band-text{color:var(--pd-ink-2);max-width:880px}

/* ---------- Archive ---------- */
.pd-arch-h2{font-size:20px;color:var(--pd-primary);margin:26px 0 14px}
.pd-404{text-align:center;padding:60px 0}

/* ---------- Footer ---------- */
.pd-footer{background:#0a2540;color:#cfe0f5;margin-top:50px;padding:40px 0 24px}
.pd-footer-inner{max-width:1180px;margin:0 auto;padding:0 24px;display:flex;flex-wrap:wrap;gap:40px;justify-content:space-between}
.pd-footer-brand{font-size:18px;font-weight:800;color:#fff;margin-bottom:10px}
.pd-footer p{margin:0;font-size:14px;max-width:420px}
.pd-footer-links{display:flex;flex-wrap:wrap;gap:8px 20px}
.pd-footer-links a{color:#9fc1e6;font-size:14px}
.pd-footer-links a:hover{color:#fff}
.pd-footer-bottom{text-align:center;margin-top:28px;padding-top:18px;border-top:1px solid rgba(255,255,255,.12);font-size:13px;color:#7f9bc0}

/* ---------- Responsive ---------- */
@media (max-width:900px){
  .pd-layout{grid-template-columns:1fr;gap:24px}
  .pd-aside{position:static;top:auto}
  .pd-toc{display:none}
  .pd-itemlist{grid-template-columns:1fr}
  .pd-hero-title{font-size:30px}
  .pd-nav{display:none;position:absolute;top:64px;left:0;right:0;background:#0a2540;flex-direction:column;padding:12px 24px;gap:2px}
  .pd-nav.open{display:flex}
  .pd-nav>a,.pd-has-sub>a{padding:10px 8px}
  .pd-sub{position:static;box-shadow:none;background:rgba(255,255,255,.06);margin:0 0 6px}
  .pd-sub a{color:#dbe7fb}
  .pd-nav-toggle{display:flex}
  .pd-has-sub:hover .pd-sub{display:none}
  .pd-has-sub.open .pd-sub{display:block}
  .pd-capsule{right:12px}
  .pd-cap-btn{width:44px;height:44px}
}