/* =============================================================
   DeckOS · Shared Design System
   Apple deep-black + Pentagram editorial-warm + Oversized type
   ============================================================= */

/* ---------- Reset ---------- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
body{
  font-family:"SF Pro Display","SF Pro Text",-apple-system,BlinkMacSystemFont,"Helvetica Neue","PingFang SC","Microsoft YaHei",sans-serif;
  color:#1d1d1f;background:#fbfbfd;line-height:1.5;overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:none;cursor:pointer}
img,svg{max-width:100%;display:block}
input,textarea{font:inherit;color:inherit}

/* ---------- Tokens ---------- */
:root{
  /* neutral */
  --bg:#fbfbfd; --bg-warm:#f5efe4; --bg-deep:#0a0a0c;
  --ink:#1d1d1f; --ink-soft:#515154; --ink-dim:#86868b; --ink-ghost:#b0b0b7;
  --line:#d2d2d7; --line-soft:#e8e8ed;
  /* brand accents (Apple Intelligence mesh palette) */
  --accent:#0071e3; --accent-dark:#0058b0;
  --mesh-a:#0070f3; --mesh-b:#8b5cf6; --mesh-c:#ec4899; --mesh-d:#f59e0b;
  /* editorial accents */
  --warm-cream:#f5efe4; --warm-amber:#c9a961; --warm-ink:#2b2219;
  /* radii */
  --r-sm:8px; --r-md:14px; --r-lg:20px; --r-xl:28px; --r-xxl:36px;
  /* shadows */
  --shadow-card:0 2px 8px rgba(0,0,0,.04),0 10px 32px rgba(0,0,0,.06);
  --shadow-hover:0 4px 14px rgba(0,0,0,.08),0 24px 48px rgba(0,0,0,.12);
  --shadow-dark:0 2px 12px rgba(0,0,0,.4),0 24px 60px rgba(0,0,0,.5);
}

/* ---------- Typography scale ---------- */
.h-display{font-size:clamp(56px,8vw,112px);font-weight:700;line-height:.98;letter-spacing:-.035em}
.h-1{font-size:clamp(44px,5vw,72px);font-weight:700;line-height:1.04;letter-spacing:-.028em}
.h-2{font-size:clamp(32px,3.6vw,52px);font-weight:700;line-height:1.08;letter-spacing:-.02em}
.h-3{font-size:clamp(22px,2.2vw,28px);font-weight:600;line-height:1.22;letter-spacing:-.012em}
.eyebrow{font-size:12px;font-weight:600;letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}
.kicker-rule{display:inline-flex;align-items:center;gap:10px;font-size:12px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-soft)}
.kicker-rule::before{content:"";width:22px;height:1px;background:currentColor}

/* Gradient text */
.grad{background:linear-gradient(100deg,var(--mesh-a) 0%,var(--mesh-b) 45%,var(--mesh-c) 85%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.grad-ink{background:linear-gradient(180deg,#fff 0%,#fff 55%,#b0b0b7 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}

/* ---------- Layout ---------- */
.wrap{max-width:1280px;margin:0 auto;padding:0 32px}
.section{padding:120px 0}
.section-sm{padding:80px 0}

/* ---------- Top Nav ---------- */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:100;height:52px;
  background:rgba(251,251,253,.72);backdrop-filter:saturate(180%) blur(20px);
  -webkit-backdrop-filter:saturate(180%) blur(20px);
  border-bottom:1px solid rgba(0,0,0,.06);
}
.nav.on-dark{background:rgba(10,10,12,.64);border-bottom-color:rgba(255,255,255,.08);color:#f5f5f7}
.nav-inner{max-width:1280px;margin:0 auto;height:100%;padding:0 32px;display:flex;align-items:center;gap:36px;font-size:14px}
.nav-logo{font-weight:700;letter-spacing:-.01em;display:flex;align-items:center;gap:9px;font-size:15px}
.nav-logo .dot{width:11px;height:11px;border-radius:3px;background:conic-gradient(from 210deg,var(--mesh-a),var(--mesh-b),var(--mesh-c),var(--mesh-d),var(--mesh-a));box-shadow:0 0 14px rgba(139,92,246,.38)}
.nav-links{display:flex;gap:28px;color:var(--ink-soft)}
.nav.on-dark .nav-links{color:rgba(255,255,255,.6)}
.nav-links a{opacity:.82;transition:opacity .2s,color .2s;position:relative}
.nav-links a:hover,.nav-links a.active{opacity:1;color:var(--ink)}
.nav.on-dark .nav-links a:hover,.nav.on-dark .nav-links a.active{color:#fff}
.nav-links a.active::after{content:"";position:absolute;left:0;right:0;bottom:-18px;height:2px;background:currentColor;border-radius:1px}
.nav-cta{margin-left:auto;background:var(--ink);color:#fff;padding:8px 18px;border-radius:999px;font-size:13px;font-weight:500;transition:transform .2s,background .2s}
.nav.on-dark .nav-cta{background:#fff;color:#000}
.nav-cta:hover{transform:translateY(-1px)}

/* ---------- Buttons ---------- */
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 28px;border-radius:999px;font-size:16px;font-weight:500;transition:transform .2s,box-shadow .2s,background .2s,color .2s;cursor:pointer;white-space:nowrap}
.btn-primary{background:var(--ink);color:#fff}
.btn-primary:hover{background:#000;transform:translateY(-2px);box-shadow:0 12px 28px rgba(0,0,0,.2)}
.btn-primary-light{background:#fff;color:#000}
.btn-primary-light:hover{transform:translateY(-2px);box-shadow:0 12px 28px rgba(255,255,255,.2)}
.btn-ghost{background:transparent;color:inherit;border:1px solid currentColor}
.btn-ghost:hover{background:rgba(0,0,0,.05)}
.btn-ghost-dark{background:rgba(255,255,255,.06);color:#fff;border:1px solid rgba(255,255,255,.2)}
.btn-ghost-dark:hover{background:rgba(255,255,255,.12)}
.btn-sm{padding:8px 16px;font-size:13px}
.btn .arrow{transition:transform .2s}
.btn:hover .arrow{transform:translateX(4px)}

/* ---------- Tags / pills ---------- */
.pill{display:inline-flex;align-items:center;gap:6px;font-size:12px;font-weight:500;padding:4px 10px;border-radius:999px;background:rgba(0,0,0,.06);color:var(--ink-soft)}
.pill-live::before{content:"";width:6px;height:6px;border-radius:50%;background:#2dd47c;box-shadow:0 0 8px #2dd47c;animation:pulseDot 1.4s infinite}
.pill-dark{background:rgba(255,255,255,.08);color:rgba(255,255,255,.82);border:1px solid rgba(255,255,255,.14)}
.pill-canon{background:var(--warm-cream);color:var(--warm-ink);border:1px solid rgba(201,169,97,.3)}

@keyframes pulseDot{0%,100%{opacity:1;transform:scale(1)}50%{opacity:.5;transform:scale(.8)}}

/* ---------- Mesh backdrop utility ---------- */
.mesh-bg{position:absolute;inset:-20%;pointer-events:none;filter:blur(32px);z-index:0}
.mesh-bg.v1{background:
  radial-gradient(ellipse 40% 60% at 22% 30%, rgba(0,112,243,.35), transparent 60%),
  radial-gradient(ellipse 35% 55% at 78% 28%, rgba(236,72,153,.28), transparent 60%),
  radial-gradient(ellipse 50% 40% at 50% 85%, rgba(139,92,246,.32), transparent 65%),
  radial-gradient(ellipse 30% 30% at 90% 70%, rgba(245,158,11,.22), transparent 70%);
  animation:meshDrift 22s ease-in-out infinite alternate;
}
.mesh-bg.v2{background:
  radial-gradient(ellipse 45% 50% at 20% 40%, rgba(201,169,97,.28), transparent 60%),
  radial-gradient(ellipse 40% 45% at 80% 60%, rgba(139,92,246,.22), transparent 60%);
  animation:meshDrift 28s ease-in-out infinite alternate;
}
@keyframes meshDrift{
  0%{transform:translate(0,0) scale(1)}
  50%{transform:translate(-3%,2%) scale(1.05)}
  100%{transform:translate(3%,-2%) scale(1.02)}
}

/* ---------- Reveal ---------- */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .8s cubic-bezier(.2,.8,.2,1),transform .8s cubic-bezier(.2,.8,.2,1)}
.reveal.on{opacity:1;transform:none}

/* ---------- Footer ---------- */
footer{background:#000;color:rgba(255,255,255,.4);border-top:1px solid rgba(255,255,255,.08);padding:56px 32px 40px}
.footer-inner{max-width:1280px;margin:0 auto;display:flex;gap:40px;align-items:flex-start;justify-content:space-between;flex-wrap:wrap}
.footer-brand{font-size:13px}
.footer-brand .n{font-weight:700;color:#fff;font-size:15px;margin-bottom:6px;display:flex;align-items:center;gap:9px}
.footer-brand .n .dot{width:10px;height:10px;border-radius:3px;background:conic-gradient(from 210deg,var(--mesh-a),var(--mesh-b),var(--mesh-c),var(--mesh-d),var(--mesh-a))}
.footer-cols{display:flex;gap:64px;font-size:13px}
.footer-cols h4{font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:rgba(255,255,255,.45);margin-bottom:14px;font-weight:600}
.footer-cols a{display:block;color:rgba(255,255,255,.6);padding:5px 0;transition:color .2s}
.footer-cols a:hover{color:#fff}
.footer-legal{margin-top:32px;font-size:11px;color:rgba(255,255,255,.3);text-align:center;padding-top:24px;border-top:1px solid rgba(255,255,255,.06)}

/* ---------- Deck page thumbnail primitives ----------
   Used on kanban/gallery to render fake "deck page" cards in pure CSS */
.page-thumb{
  aspect-ratio:16/9;border-radius:var(--r-md);overflow:hidden;
  position:relative;background:#fff;border:1px solid var(--line-soft);
  display:flex;flex-direction:column;padding:12px 14px;
  transition:transform .25s cubic-bezier(.2,.8,.2,1),box-shadow .25s;
}
.page-thumb:hover{transform:translateY(-3px);box-shadow:var(--shadow-hover)}
.page-thumb .pt-no{font-size:9px;color:var(--ink-dim);font-weight:600;letter-spacing:.05em;margin-bottom:4px}
.page-thumb .pt-title{font-size:13px;font-weight:700;line-height:1.2;letter-spacing:-.01em;color:var(--ink)}
.page-thumb .pt-body{flex:1;display:flex;align-items:center;justify-content:center;padding:8px 0}
.page-thumb .pt-footer{display:flex;gap:4px;flex-wrap:wrap}
.page-thumb .pt-footer .chip{font-size:8px;color:var(--ink-dim);padding:1px 5px;border-radius:4px;background:var(--line-soft);font-weight:500}

/* skeleton / refined states */
.page-thumb.skeleton{background:linear-gradient(135deg,#f5f5f7,#ececef)}
.page-thumb.skeleton .pt-title{color:#b0b0b7}
.page-thumb.refined{border-color:var(--ink)}
.page-thumb.refined::after{
  content:"";position:absolute;inset:0;border:2px solid var(--ink);border-radius:var(--r-md);pointer-events:none;
}

/* variant backgrounds for variety */
.pt-bg-apple{background:linear-gradient(160deg,#000,#1f1f24);color:#fff}
.pt-bg-apple .pt-title{color:#fff}
.pt-bg-apple .pt-no{color:rgba(255,255,255,.45)}
.pt-bg-editorial{background:linear-gradient(160deg,#fef9ee,#ead5a0);color:var(--warm-ink)}
.pt-bg-mckinsey{background:linear-gradient(160deg,#0a2342,#1f3a60);color:#fff}
.pt-bg-mckinsey .pt-title{color:#fff}
.pt-bg-stripe{background:linear-gradient(160deg,#fff,#f4f4f8)}
.pt-bg-ink{background:linear-gradient(160deg,#f8f4ee,#d8cdbf);color:#2b2219;position:relative}
.pt-bg-natgeo{background:linear-gradient(160deg,#111,#333);color:#f5c518}
.pt-bg-natgeo .pt-title{color:#f5c518}

/* viz shapes (for thumbnails) */
.viz-bars{display:flex;align-items:flex-end;gap:4px;height:40px}
.viz-bars span{flex:1;background:currentColor;border-radius:2px;opacity:.55}
.viz-line{width:100%;height:3px;background:currentColor;border-radius:2px;opacity:.6}
.viz-dot-row{display:flex;gap:4px}
.viz-dot-row span{width:8px;height:8px;background:currentColor;border-radius:50%;opacity:.55}
.viz-big-num{font-size:36px;font-weight:700;letter-spacing:-.03em;line-height:1}
.viz-cols{display:grid;grid-template-columns:repeat(3,1fr);gap:3px;width:100%}
.viz-cols span{aspect-ratio:1;background:currentColor;opacity:.2;border-radius:3px}
.viz-cols span:nth-child(1){opacity:.8}
.viz-cols span:nth-child(2){opacity:.5}