/* ============================================================
   Xiangda Supply Chain - Blog (Sourcing Notes)
   Same American B2B Premium tokens as css/home.css
   ============================================================ */

:root{
  --bg:#F6F5F0;
  --bg-alt:#FBFAF6;
  --bg-raised:#ECEBE4;
  --surface:#FFFFFF;
  --surface-hover:#F8F6F0;
  --navy:#152A46;
  --navy-lift:#1B3455;
  --ink:#101A26;
  --ink-2:#3E4A5A;
  --ink-3:#5B6775;
  --on-navy:#F4F1E8;
  --on-navy-soft:#C3CDDA;
  --on-navy-muted:#94A3B8;
  --on-gold:#14243B;
  --gold:#C9A96A;
  --gold-hover:#D9BD83;
  --gold-pressed:#B8965A;
  --gold-deep:#7C5E27;
  --gold-veil:rgba(201,169,106,.10);
  --hairline:rgba(21,42,70,.12);
  --soft:rgba(21,42,70,.07);
  --strong:rgba(21,42,70,.22);
  --navy-hairline:rgba(201,169,106,.22);
  --navy-soft:rgba(244,241,232,.10);
  --scrim:rgba(255,255,255,.94);
  --focus:#7C5E27;
  --f-display:'Inter','Helvetica Neue',Arial,sans-serif;
  --f-body:'Inter','Helvetica Neue',Arial,sans-serif;
  --max:1200px;
  --gutter:40px;
  --r-xs:2px;
  --r-sm:4px;
  --r-md:8px;
  --r-pill:999px;
  --elev-1:0 1px 2px rgba(21,42,70,.06),0 10px 24px -18px rgba(21,42,70,.18);
  --elev-2:0 18px 36px -22px rgba(21,42,70,.24),0 2px 6px -2px rgba(21,42,70,.06);
  --elev-3:0 32px 64px -32px rgba(21,42,70,.30);
  --m-quick:150ms;
  --m-lift:280ms;
  --ease:cubic-bezier(.2,0,0,1);
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:76px;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;overflow-x:clip}
body{
  font-family:var(--f-body);
  font-size:16px;line-height:1.65;
  color:var(--ink-2);background:var(--bg);
  overflow-x:clip;
}
img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none}
::selection{background:rgba(201,169,106,.24);color:var(--ink)}
.container{max-width:var(--max);margin:0 auto;padding:0 var(--gutter)}
a:focus-visible,button:focus-visible{outline:2px solid var(--focus);outline-offset:2px}
.b-page-hero :focus-visible{outline-color:var(--on-navy)}

/* ---- header: white frosted, always (blog pages start on paper) ---- */
.b-header{
  position:sticky;top:0;z-index:1000;
  background:var(--scrim);
  -webkit-backdrop-filter:blur(18px) saturate(120%);
  backdrop-filter:blur(18px) saturate(120%);
}
.b-header::after{content:'';position:absolute;left:0;right:0;bottom:0;height:1px;background:var(--hairline)}
.b-head-inner{display:grid;grid-template-columns:1fr auto 1fr;align-items:center;height:76px;position:relative}
.wordmark{
  font-family:var(--f-display);font-size:24px;font-weight:600;
  letter-spacing:-.01em;color:var(--ink);line-height:1;white-space:nowrap;
}
.wordmark span{color:var(--gold-deep)}
.nav{display:flex;align-items:center;justify-content:center;gap:32px}
.nav a{
  position:relative;display:flex;align-items:center;height:44px;
  font-size:14px;font-weight:500;letter-spacing:.01em;color:var(--ink-2);
  transition:color var(--m-quick) var(--ease);
}
.nav a::after{
  content:'';position:absolute;left:0;right:0;bottom:6px;height:1px;
  background:var(--gold-deep);transform:scaleX(0);transform-origin:0 50%;
  transition:transform var(--m-quick) var(--ease);
}
.nav a:hover,.nav a.active{color:var(--ink)}
.nav a:hover::after,.nav a.active::after{transform:scaleX(1)}
.nav .nav-cta{display:none}
.nav .nav-cta::after{display:none}
.b-cta{
  justify-self:end;display:inline-flex;align-items:center;
  height:44px;padding:0 24px;border-radius:var(--r-pill);
  background:var(--gold);color:var(--on-gold);
  font-size:14px;font-weight:500;letter-spacing:.01em;white-space:nowrap;
  transition:background var(--m-quick) var(--ease);
}
.b-cta:hover{background:var(--gold-hover)}
.mobile-toggle{
  display:none;width:48px;height:48px;
  flex-direction:column;align-items:center;justify-content:center;gap:5px;
  background:none;border:1px solid var(--hairline);border-radius:var(--r-sm);
  cursor:pointer;justify-self:end;
}
.mobile-toggle span{display:block;width:20px;height:1.6px;background:var(--ink)}
.nav-backdrop{
  display:none;position:fixed;inset:0;z-index:998;
  background:rgba(21,42,70,.55);opacity:0;pointer-events:none;
  transition:opacity var(--m-quick) var(--ease);
}
body.nav-open .nav-backdrop{opacity:1;pointer-events:auto}

/* ---- navy page hero ---- */
.b-page-hero{position:relative;background:var(--navy);padding:88px 0 72px;overflow:hidden}
.b-page-hero::before{
  content:'';position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(52% 44% at 85% 0%,rgba(27,52,85,.26) 0%,transparent 62%);
}
.b-eyebrow{
  position:relative;display:flex;align-items:center;gap:12px;
  font-size:11px;font-weight:600;letter-spacing:.10em;text-transform:uppercase;color:var(--on-navy-muted);
}
.b-eyebrow::before{content:'';width:24px;height:1px;background:var(--gold);flex:0 0 auto}
.b-page-hero h1{
  position:relative;font-family:var(--f-display);font-weight:600;
  font-size:clamp(1.9rem,4.2vw,3.25rem);line-height:1.08;letter-spacing:-.03em;
  color:var(--on-navy);margin-top:20px;max-width:820px;
}
.b-page-hero .b-sub{position:relative;margin-top:20px;max-width:62ch;font-size:17px;line-height:1.6;color:var(--on-navy-soft)}
.b-meta{position:relative;margin-top:24px;display:flex;flex-wrap:wrap;gap:8px 20px;font-size:13px;color:var(--on-navy-muted)}
.b-meta a{color:var(--on-navy-soft)}
.b-meta a:hover{color:var(--on-navy)}

/* ---- article prose ---- */
.b-main{background:var(--bg)}
.b-article{max-width:760px;margin:0 auto;padding:56px var(--gutter) 80px}
.b-article h2{
  font-family:var(--f-display);font-size:24px;font-weight:600;
  letter-spacing:-.015em;line-height:1.3;color:var(--ink);margin:44px 0 14px;
}
.b-article h2:first-of-type{margin-top:8px}
.b-article p{font-size:16px;line-height:1.75;color:var(--ink-2);margin-bottom:18px}
.b-article ul,.b-article ol{margin:0 0 18px 22px;color:var(--ink-2)}
.b-article li{margin-bottom:8px;line-height:1.65}
.b-article li::marker{color:var(--gold-deep)}
.b-article a{color:var(--gold-deep);border-bottom:1px solid rgba(124,94,39,.3)}
.b-article strong{color:var(--ink);font-weight:600}
.b-article table{
  width:100%;border-collapse:collapse;margin:8px 0 24px;
  border:1px solid var(--hairline);border-radius:var(--r-md);
  background:var(--surface);box-shadow:var(--elev-1);overflow:hidden;
}
.b-article th{
  font-size:11px;font-weight:600;letter-spacing:.10em;text-transform:uppercase;color:var(--ink-3);
  text-align:left;padding:14px 20px;border-bottom:1px solid var(--hairline);background:var(--surface-hover);
}
.b-article td{padding:14px 20px;border-bottom:1px solid var(--soft);font-size:15px;line-height:1.5;color:var(--ink-2);vertical-align:top}
.b-article tr:last-child td{border-bottom:none}
.b-article td:first-child{color:var(--ink);font-weight:500}
.b-quote-panel{
  margin:40px 0;background:var(--surface);border:1px solid var(--hairline);
  border-radius:var(--r-md);box-shadow:var(--elev-1);padding:32px;
}
.b-quote-panel h3{font-family:var(--f-display);font-size:20px;font-weight:600;letter-spacing:-.01em;color:var(--ink);margin-bottom:12px}
.b-quote-panel p{font-size:15px;line-height:1.6;margin:0 0 20px}
.b-quote-panel .b-cta{justify-self:start;height:48px}
.b-related{margin-top:48px;padding-top:32px;border-top:1px solid var(--hairline)}
.b-related h4{font-size:11px;font-weight:600;letter-spacing:.10em;text-transform:uppercase;color:var(--ink-3);margin-bottom:14px}
.b-related-list{display:flex;flex-direction:column;gap:10px}
.b-related-list a{font-size:15px;font-weight:500;color:var(--ink-2);transition:color var(--m-quick) var(--ease)}
.b-related-list a:hover{color:var(--gold-deep)}

/* ---- hub cards ---- */
.hub-section{background:var(--bg);padding:64px 0 80px}
.hub-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:48px}
.b-card{
  display:flex;flex-direction:column;
  background:var(--surface);border:1px solid var(--hairline);border-radius:var(--r-sm);
  box-shadow:var(--elev-1);padding:28px;
  transition:border-color var(--m-quick) var(--ease),box-shadow var(--m-quick) var(--ease),transform var(--m-lift) var(--ease);
}
.b-card:hover{border-color:var(--strong);box-shadow:var(--elev-2);transform:translateY(-3px)}
.b-tag{
  align-self:flex-start;padding:6px 12px;border-radius:var(--r-pill);
  background:var(--gold-veil);border:1px solid var(--hairline);
  font-size:11px;font-weight:600;letter-spacing:.10em;text-transform:uppercase;color:var(--gold-deep);
}
.b-card h2{font-family:var(--f-display);font-size:22px;font-weight:600;letter-spacing:-.015em;line-height:1.25;color:var(--ink);margin-top:16px}
.b-card p{font-size:15px;line-height:1.6;color:var(--ink-2);margin-top:10px}
.b-card-date{margin-top:auto;padding-top:16px;font-size:12px;color:var(--ink-3)}

/* ---- footer: navy, compact ---- */
.b-footer{background:var(--navy);border-top:1px solid var(--navy-hairline);padding:48px 0 32px}
.b-footer .container{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:20px 32px}
.b-footer .wordmark{color:var(--on-navy)}
.b-footer .wordmark span{color:var(--gold)}
.b-foot-links{display:flex;flex-wrap:wrap;gap:8px 28px;font-size:14px;color:var(--on-navy-soft)}
.b-foot-links a:hover{color:var(--on-navy)}
.b-copy{width:100%;padding-top:20px;border-top:1px solid var(--navy-soft);font-size:14px;color:var(--on-navy-muted)}

/* ---- responsive ---- */
@media (max-width:767px){
  html{scroll-padding-top:64px}
  .container{padding:0 20px}
  .b-head-inner{grid-template-columns:1fr auto;height:64px}
  .b-cta{display:none}
  .mobile-toggle{display:flex}
  .nav-backdrop{display:block}
  .nav{
    position:fixed;top:72px;left:16px;right:16px;z-index:999;
    flex-direction:column;align-items:stretch;gap:4px;
    background:var(--surface);border:1px solid var(--hairline);border-radius:var(--r-md);
    box-shadow:var(--elev-3);padding:16px 24px 20px;
    opacity:0;visibility:hidden;transform:translateY(-10px);
    transition:opacity var(--m-quick) var(--ease),transform var(--m-quick) var(--ease),
      visibility 0s linear var(--m-quick);
  }
  .nav.open{
    opacity:1;visibility:visible;transform:translateY(0);
    transition:opacity var(--m-quick) var(--ease),transform var(--m-quick) var(--ease);
  }
  .nav a{height:44px;justify-content:flex-start;font-size:18px;font-weight:600;letter-spacing:-.01em;color:var(--ink)}
  .nav a::after{display:none}
  .nav .nav-cta{
    display:inline-flex;align-items:center;justify-content:center;
    margin-top:12px;height:52px;padding:0 32px;border-radius:var(--r-pill);
    font-size:14px;font-weight:500;background:var(--gold);color:var(--on-gold);
  }
  .b-page-hero{padding:64px 0 48px}
  .b-article{padding:44px 20px 64px}
  .hub-section{padding:48px 0 64px}
  .hub-grid{grid-template-columns:1fr}
}