/* ==========================================================================
   JC AI Systems · Learning Hub
   Same tokens as the homepage (Archivo, grayscale ramp, #0049FF), but on a
   normal 16px root instead of the homepage's fluid vw root, because long-form
   reading needs a size that does not collapse on a phone.
   ========================================================================== */
@font-face{
  font-family:"Archivo";
  src:url("../assets/archivo.woff2") format("woff2");
  font-weight:100 900;
  font-display:swap;
}
:root{
  --100:#FEFEFE; --200:#F9F9F9; --400:#dcdcdc; --600:#A5A5A5;
  --700:#6F6F6F; --800:#3d3d3d; --900:#1f1f1f; --1000:#000F22;
  --brand:#3376FF; --brand-lift:#7CA6FF;
  --ground:var(--100); --ink:var(--1000); --ink-muted:var(--700); --rule:var(--400);
  --wrap:min(92%,72rem);
  --font:"Archivo",-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:none;-webkit-font-smoothing:antialiased;scroll-behavior:smooth}
body{
  margin:0;background:var(--ground);color:var(--ink);
  font-family:var(--font);font-size:1.0625rem;line-height:1.65;font-weight:400;
}
img{max-width:100%;display:block}
a{color:var(--brand)}
.container{width:var(--wrap);margin-inline:auto}

/* ---- nav ---- */
.nav{position:sticky;top:0;z-index:50;background:var(--1000);border-bottom:1px solid var(--900)}
.nav__in{display:flex;align-items:center;justify-content:space-between;gap:1.5rem;height:4.75rem;width:var(--wrap);margin-inline:auto}
.brand{display:flex;align-items:center;gap:.75rem;text-decoration:none;color:var(--100)}
.brand img{width:2.5rem;height:auto}
.brand span{font-weight:600;letter-spacing:-.01em;font-size:1rem}
.nav__links{display:flex;gap:1.75rem;list-style:none;margin:0;padding:0}
.nav__links a{color:var(--600);text-decoration:none;font-size:.9rem}
.nav__links a:hover,.nav__links a[aria-current]{color:var(--100)}
@media(max-width:680px){.nav__links{display:none}}

/* ---- buttons ---- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  padding:.85rem 1.7rem;border:1px solid var(--1000);border-radius:999px;background:var(--1000);color:var(--100);
  text-decoration:none;font-weight:600;font-size:.9rem;letter-spacing:.01em;
  transition:background .18s ease,color .18s ease,border-color .18s ease;
}
.btn:hover{background:var(--brand);border-color:var(--brand);color:#fff}
.btn--ghost{background:transparent;color:var(--1000)}
.btn--ghost:hover{background:var(--1000);color:var(--100);border-color:var(--1000)}
.btn--sm{padding:.6rem 1.2rem;font-size:.82rem}
.btn--light{background:#fff;border-color:#fff;color:var(--1000)}
.btn--light:hover{background:var(--brand-lift);border-color:var(--brand-lift);color:#fff}

/* ---- shared type ---- */
.eyebrow{
  display:inline-flex;align-items:center;gap:.6rem;
  font-size:.72rem;font-weight:700;letter-spacing:.18em;text-transform:uppercase;color:var(--brand);
  margin:0 0 1.1rem;
}
.eyebrow::before{content:"";width:.45rem;height:.45rem;background:var(--brand)}
h1,h2,h3,h4{letter-spacing:-.03em;line-height:1.08;margin:0;font-weight:700}
h1{font-size:clamp(2.1rem,5vw,3.4rem)}
h2{font-size:clamp(1.5rem,3vw,2.1rem);margin:3.2rem 0 1rem}
h3{font-size:1.2rem;margin:2.2rem 0 .7rem}
p{margin:0 0 1.15rem}
.lede{font-size:1.2rem;color:var(--ink-muted);max-width:62ch}

/* ---- hub ---- */
.hub-head{padding:5rem 0 3rem;border-bottom:1px solid var(--rule)}
.cards{display:grid;gap:1.4rem;background:transparent;border:0;margin:3rem 0 5rem}
@media(min-width:900px){.cards{grid-template-columns:repeat(2,1fr)}}
.card{background:var(--100);border:1px solid var(--rule);border-radius:12px;padding:2.4rem 2rem 2.6rem;display:flex;flex-direction:column;text-decoration:none;color:inherit;transition:transform .22s cubic-bezier(.16,1,.3,1),box-shadow .22s ease,border-color .22s ease}
.card:hover{transform:translateY(-4px);box-shadow:0 1.4rem 3rem -1.2rem rgba(0,15,34,.18);border-color:var(--brand)}
.card__tag{font-size:.7rem;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--brand);margin-bottom:1.1rem}
.card h3{margin:0 0 .7rem;font-size:1.35rem}
.card p{color:var(--ink-muted);font-size:.98rem;margin:0 0 1.4rem}
.card__more{margin-top:auto;font-weight:600;font-size:.9rem;color:var(--1000)}
.card__more::after{content:" \2192"}

/* ---- article ---- */
.crumb{padding:2rem 0 0;font-size:.85rem;color:var(--ink-muted)}
.crumb a{color:var(--ink-muted);text-decoration:none}
.crumb a:hover{color:var(--brand)}
.article{padding:1.5rem 0 4rem}
.article__head{max-width:62ch;padding-bottom:2.2rem;border-bottom:1px solid var(--rule);margin-bottom:2.6rem}
.article__meta{font-size:.85rem;color:var(--ink-muted);margin-top:1.2rem}
.prose{max-width:66ch}
.prose h2{border-top:1px solid var(--rule);padding-top:2.4rem}
.prose ul,.prose ol{margin:0 0 1.3rem;padding-left:1.3rem}
.prose li{margin-bottom:.55rem}
.prose strong{font-weight:700}
.callout{background:var(--200);border:1px solid var(--rule);border-left:3px solid var(--brand);border-radius:12px;padding:1.5rem 1.7rem;margin:2rem 0}
.callout p:last-child{margin-bottom:0}
.steps{counter-reset:s;list-style:none;padding:0;margin:1.6rem 0 2rem}
.steps li{counter-increment:s;position:relative;padding-left:3rem;margin-bottom:1.2rem}
.steps li::before{
  content:counter(s,decimal-leading-zero);position:absolute;left:0;top:.05rem;
  font-weight:700;color:var(--brand);font-size:.95rem;letter-spacing:.02em;
}

/* ---- cta ---- */
.cta{background:var(--1000);color:var(--100);padding:4rem 0;margin-top:4rem}
.cta h2{margin:0 0 1rem;border:0;padding:0;color:var(--100)}
.cta p{color:var(--600);max-width:52ch}
.cta .row{display:flex;flex-wrap:wrap;gap:.9rem;margin-top:1.8rem}

/* ---- footer ---- */
.foot{background:var(--1000);color:var(--600);padding:3rem 0;font-size:.88rem;border-top:1px solid var(--900)}
.foot a{color:var(--600);text-decoration:none}
.foot a:hover{color:var(--100)}
.foot__in{display:flex;flex-wrap:wrap;gap:1rem;justify-content:space-between;align-items:center}

/* ============================ Article figures ============================ */
figure.fig{ margin:2.8rem 0 3rem; border:1px solid var(--rule); border-radius:12px;
  background:var(--100); padding:2rem 1.8rem 1.4rem; overflow:hidden }
figure.fig svg{ width:100%; height:auto; display:block }
figure.fig figcaption{ margin-top:1.2rem; padding-top:1.1rem; border-top:1px solid var(--rule);
  font-size:.86rem; line-height:1.5; color:var(--ink-muted) }
figure.fig figcaption b{ color:var(--ink); font-weight:600 }
.fig-t{ font:600 14px/1.2 var(--font); fill:#000F22 }
.fig-l{ font:500 12.5px/1.2 var(--font); fill:#000F22 }
.fig-m{ font:500 11px/1.2 var(--font); fill:#6F6F6F }
.fig-v{ font:700 13px/1.2 var(--font); fill:#000F22 }
.fig-big{ font:800 21px/1 var(--font); fill:#3376FF }
.fig-grid{ stroke:#DCDCDC; stroke-width:1 }
.fig-bar{ fill:#3376FF }
.fig-rule{ stroke:#DCDCDC; stroke-width:1 }
.fig-box{ fill:#F9F9F9; stroke:#DCDCDC; stroke-width:1 }
.fig-arrow{ stroke:#6F6F6F; stroke-width:1.5; fill:none }