/* Learn AI — shared design system: tokens + top nav + footer.
   Include on every page:  <link rel="stylesheet" href="/assets/shell.css">
   Pair with /assets/shell.js which injects the nav + footer markup. */
:root{
  --cy:#22d3ee;--vi:#a855f7;--gr:#4ade80;--am:#fbbf24;--rd:#ff6b6b;
  --tx:#eaf2ff;--dim:#93a7c8;--bg:#04050b;--pan:#0a0f1c;--pan2:#070c17;--bd:#17233b;
  --mono:ui-monospace,'SFMono-Regular',Consolas,Menlo,monospace;
  --grad:linear-gradient(90deg,var(--cy),var(--vi));
  --maxw:1120px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--tx);line-height:1.6;
  font-family:ui-sans-serif,system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;
  -webkit-font-smoothing:antialiased}
a{color:var(--cy);text-decoration:none}
img{max-width:100%}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.grad-text{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.btn{display:inline-flex;align-items:center;gap:8px;padding:12px 22px;border-radius:12px;font-weight:800;
  font-size:14px;cursor:pointer;border:0;background:var(--grad);color:#04050b;text-decoration:none;transition:transform .15s}
.btn:hover{transform:translateY(-1px)}
.btn.ghost{background:transparent;color:var(--tx);border:1px solid var(--bd)}
.btn.sm{padding:9px 15px;font-size:13px}

/* ── Top nav ───────────────────────────────────────────────── */
.mk-nav{position:sticky;top:0;z-index:100;backdrop-filter:blur(12px);
  background:rgba(4,5,11,.72);border-bottom:1px solid var(--bd)}
.mk-nav .row{display:flex;align-items:center;gap:18px;height:60px}
.mk-brand{display:inline-flex;align-items:center;font-weight:800;font-size:17px;letter-spacing:.3px;white-space:nowrap;color:var(--tx)}
.mk-logo{width:26px;height:26px;display:inline-block;margin-right:8px}
.mk-links{display:flex;align-items:center;gap:16px;margin-left:10px;flex:1}
.mk-links a{color:var(--dim);font-size:13.5px;font-weight:600;white-space:nowrap}
.mk-links a:hover,.mk-links a.active{color:var(--tx)}
.mk-right{display:flex;align-items:center;gap:12px}
.mk-auth{color:var(--dim);font-size:14px;font-weight:700}
.mk-auth:hover{color:var(--tx)}
.mk-burger{display:none;background:none;border:1px solid var(--bd);border-radius:9px;color:var(--tx);
  width:40px;height:38px;font-size:18px;cursor:pointer}
@media(max-width:980px){
  .mk-links{position:fixed;inset:60px 0 auto 0;flex-direction:column;background:rgba(4,5,11,.98);
    border-bottom:1px solid var(--bd);padding:12px 20px 20px;gap:2px;display:none}
  .mk-links.open{display:flex}
  .mk-links a{padding:12px 4px;font-size:16px;border-bottom:1px solid rgba(23,35,59,.5)}
  .mk-burger{display:block}
  .mk-right{margin-left:auto} /* .mk-links is fixed/out-of-flow on mobile — push Sign in + ☰ to the right */
  .mk-right .btn{display:none}
}

/* ── Courses mega-menu ─────────────────────────────────────── */
.mk-mega-wrap{position:relative;display:inline-flex;align-items:center;align-self:stretch}
.mk-mega-trigger{display:inline-flex;align-items:center;gap:5px;color:var(--dim);font-size:13.5px;font-weight:600;white-space:nowrap;cursor:pointer}
.mk-mega-trigger:hover,.mk-mega-wrap:hover .mk-mega-trigger{color:var(--tx)}
.mk-mega-trigger .caret{font-size:9px;opacity:.7}
.mk-mega{position:fixed;left:0;right:0;top:60px;display:none;z-index:99;
  background:rgba(6,10,20,.98);border-top:1px solid var(--bd);border-bottom:1px solid var(--bd);
  backdrop-filter:blur(14px);box-shadow:0 30px 60px rgba(0,0,0,.5)}
/* transparent bridge over the gap between the trigger and the panel so the
   pointer never leaves the hover zone in transit (kills the flicker/hide). */
.mk-mega::before{content:"";position:absolute;left:0;right:0;top:-18px;height:18px}
.mk-mega-wrap:hover .mk-mega{display:block}
.mk-mega .inner{max-width:var(--maxw);margin:0 auto;padding:24px 20px;display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:26px}
/* rich rows: icon + title + one-line description — so every menu says what's inside */
.mk-mega a.rich{align-items:flex-start;padding:7px 0}
.mk-mega a.rich .em{margin-top:1px}
.mk-mega a .rl{display:flex;flex-direction:column;gap:1px;min-width:0}
.mk-mega a .rl b{color:var(--tx);font-weight:700;font-size:13.5px;line-height:1.25}
.mk-mega a .rl small{color:var(--mut);font-size:11.5px;line-height:1.35}
.mk-mega a.rich:hover .rl b{color:var(--cy)}
.mk-mega h5{font-size:11px;letter-spacing:1.4px;text-transform:uppercase;color:var(--cy);font-weight:800;margin:0 0 10px}
.mk-mega a{display:flex;align-items:center;gap:9px;color:var(--dim);font-size:13.5px;font-weight:600;padding:6px 0;text-decoration:none}
.mk-mega a:hover{color:var(--tx)}
.mk-mega a .em{width:20px;text-align:center;flex:0 0 auto}
.mk-mega a .lvl{margin-left:auto;font-size:9.5px;font-weight:800;color:#5f7290;border:1px solid var(--bd);border-radius:999px;padding:1px 7px}
.mk-mega .feat{margin-top:12px;background:linear-gradient(180deg,rgba(34,211,238,.1),rgba(168,85,247,.06));border:1px solid rgba(34,211,238,.3);border-radius:14px;padding:14px}
.mk-mega .feat b{display:block;color:var(--tx);font-size:14px;margin-bottom:4px}
.mk-mega .feat p{margin:0 0 10px;font-size:12px;color:var(--dim);line-height:1.5}
.mk-mega .feat a.btn{display:flex;justify-content:center;color:#04050b;padding:10px}

/* ── Grouped nav: triggers + panels (wide "Learn" reuses .mk-mega above) ── */
.mk-grp{position:relative;display:inline-flex;align-items:center;align-self:stretch}
.mk-grp-trig{display:inline-flex;align-items:center;gap:5px;color:var(--dim);font-size:13.5px;font-weight:600;white-space:nowrap;cursor:pointer}
.mk-grp-trig .caret{font-size:9px;opacity:.7;transition:transform .2s}
.mk-grp:hover .mk-grp-trig,.mk-grp.open>.mk-grp-trig,.mk-grp-trig.active,.mk-grp-trig:hover{color:var(--tx)}
.mk-grp.open>.mk-grp-trig .caret{transform:rotate(180deg)}
.mk-panel{display:none}
.mk-panel::before{content:"";position:absolute;left:0;right:0;top:-16px;height:16px}
/* Panel visibility is driven by an .open class set in JS (hover-intent + click),
   not raw :hover — that eliminates the gap-flicker when moving into the panel. */
.mk-grp.open .mk-panel{display:block}
.mk-drop{position:absolute;left:0;top:100%;min-width:240px;z-index:99;padding:10px;
  background:rgba(6,10,20,.98);border:1px solid var(--bd);border-radius:14px;
  backdrop-filter:blur(14px);box-shadow:0 24px 50px rgba(0,0,0,.5)}
.mk-drop a{display:flex;align-items:center;gap:10px;color:var(--dim);font-size:13.5px;font-weight:600;padding:9px 10px;border-radius:9px;text-decoration:none}
.mk-drop a:hover{color:var(--tx);background:rgba(120,170,255,.06)}
.mk-drop a .em{width:20px;text-align:center;flex:0 0 auto}
@media(max-width:980px){
  .mk-grp{display:block;width:100%}
  .mk-grp-trig{display:flex;justify-content:space-between;width:100%;padding:12px 4px;font-size:16px;border-bottom:1px solid rgba(23,35,59,.5)}
  .mk-grp .caret{transition:transform .2s}
  .mk-grp.open .caret{transform:rotate(180deg)}
  .mk-panel{position:static;background:none;border:0;box-shadow:none;backdrop-filter:none;padding:2px 0 10px 12px}
  .mk-panel::before{display:none}
  .mk-grp.open .mk-panel{display:block}
  .mk-mega{position:static;top:auto;border:0;box-shadow:none;background:none}
  .mk-mega .inner{grid-template-columns:1fr;gap:2px;padding:0;max-width:none}
  .mk-mega h5{margin:12px 0 4px}
  .mk-mega .feat{margin:8px 0}
  .mk-drop{min-width:0}
  .mk-panel a{font-size:15px;border-bottom:0}
}

/* ── Footer ────────────────────────────────────────────────── */
.mk-foot{border-top:1px solid var(--bd);margin-top:70px;background:var(--pan2);text-align:left}
.mk-foot .cols{display:grid;grid-template-columns:1.7fr 1fr 1fr 1fr 1.05fr;gap:26px;padding:40px 0 26px;text-align:left}
.mk-foot .cols>div{text-align:left}
.mk-foot h4{font-size:12px;letter-spacing:1.5px;text-transform:uppercase;color:var(--dim);margin:0 0 14px}
.mk-foot a{display:block;color:var(--dim);font-size:14px;padding:5px 0}
.mk-foot a:hover{color:var(--tx)}
.mk-foot .lead p{color:var(--dim);font-size:13.5px;max-width:300px;margin:10px 0 14px}
/* footer weekly-signal email capture — elegant single-pill (input + button share
   one rounded, focus-ringed container). Scoped to .mk-foot so page-level input
   rules (e.g. the homepage's own forms) can't override the field styling. */
.mk-foot .mk-sub{margin:2px 0 18px;max-width:340px}
.mk-foot .mk-sub label{display:block;font-size:12.5px;color:var(--dim);margin-bottom:10px;line-height:1.5}
.mk-foot .mk-sub label b{color:var(--tx);font-weight:700}
.mk-foot .mk-sub .row{display:flex;align-items:center;gap:5px;background:var(--pan);border:1px solid var(--bd);
  border-radius:12px;padding:5px 5px 5px 4px;transition:border-color .16s,box-shadow .16s}
.mk-foot .mk-sub .row:focus-within{border-color:var(--cy);box-shadow:0 0 0 3px rgba(34,211,238,.14)}
.mk-foot .mk-sub input{flex:1;min-width:0;border:0;background:transparent;color:var(--tx);
  font-size:13.5px;font-family:inherit;padding:8px 10px;box-shadow:none}
.mk-foot .mk-sub input::placeholder{color:#5f7290}
.mk-foot .mk-sub input:focus{outline:none;box-shadow:none}
.mk-foot .mk-sub button{flex:0 0 auto;border:0;border-radius:9px;background:var(--grad);color:#04050b;
  font-weight:800;font-size:12.5px;letter-spacing:.2px;padding:8px 16px;cursor:pointer;white-space:nowrap;
  transition:transform .15s,filter .15s}
.mk-foot .mk-sub button:hover{transform:translateY(-1px);filter:brightness(1.06)}
.mk-foot .mk-sub button:disabled{opacity:.55;cursor:default;transform:none;filter:none}
.mk-foot .mk-sub .msg{font-size:12px;margin:9px 2px 0;min-height:1px}
.mk-foot .mk-sub .msg.ok{color:var(--gr)}
.mk-foot .mk-sub .msg.err{color:var(--rd)}
.mk-social{display:flex;gap:10px;flex-wrap:wrap}
.mk-social a{display:grid;place-items:center;width:38px;height:38px;border:1px solid var(--bd);border-radius:10px;padding:0}
.mk-social a:hover{border-color:var(--cy);background:rgba(34,211,238,.08)}
.mk-social svg{width:18px;height:18px;fill:var(--dim)}
.mk-social a:hover svg{fill:var(--cy)}
.mk-legal{border-top:1px solid var(--bd);padding:18px 0;display:flex;justify-content:space-between;
  flex-wrap:wrap;gap:10px;color:#5f7290;font-size:12px}
/* the generic `.mk-foot a` rule must NOT restyle the CTA button or the legal links */
.mk-foot a.btn{display:inline-flex;color:#04050b;padding:9px 15px}
.mk-foot a.btn:hover{color:#04050b}
.mk-legal a{display:inline;padding:0}
@media(max-width:760px){.mk-foot .cols{grid-template-columns:1fr 1fr;gap:24px}}
@media(max-width:440px){.mk-foot .cols{grid-template-columns:1fr}}

/* ── Shared page furniture ─────────────────────────────────── */
.eyebrow{font-size:12px;letter-spacing:2.5px;text-transform:uppercase;color:var(--cy);font-weight:800}
.section{padding:56px 0}
.lead-h1{font-size:clamp(30px,5vw,52px);line-height:1.08;letter-spacing:-.02em;margin:12px 0 14px;font-weight:800}
.sub{color:var(--dim);font-size:clamp(15px,2vw,18px);max-width:640px}
.card{background:var(--pan);border:1px solid var(--bd);border-radius:16px;padding:22px}
.pill{display:inline-block;font-size:11px;font-weight:800;letter-spacing:.5px;padding:4px 10px;border-radius:999px;
  border:1px solid var(--bd);color:var(--dim)}