:root{
  --primary:#14b8a6;
  --secondary:#0f766e;
  --accent:#db2777;
  --bg:#ffffff;
  --surface:#f0fdfa;
  --surface-alt:#ccfbf1;
  --text:#134e4a;
  --muted:#6b7280;
  --border:#99f6e4;
  --row-alt:#f0fdfa;
  --radius:6px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Oxygen,Ubuntu,Cantarell,"Helvetica Neue",Arial,sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.65;
  font-size:16px;
}
a{color:var(--secondary);text-decoration:underline}
a:hover{color:var(--accent)}
img,svg{max-width:100%;height:auto;display:block}
.container{max-width:960px;margin:0 auto;padding:0 16px}

/* Header */
.site-header{
  position:sticky;top:0;z-index:50;
  background:linear-gradient(90deg,var(--primary) 0%,var(--secondary) 60%,var(--accent) 100%);
  color:#fff;
  box-shadow:0 2px 8px rgba(19,78,74,.15);
}
.site-header .container{display:flex;flex-wrap:wrap;align-items:center;gap:12px;padding:10px 16px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:#fff;font-weight:700;font-size:1.1rem}
.brand img{width:36px;height:36px;background:#fff;border-radius:8px;padding:3px}
.nav{margin-left:auto;display:flex;flex-wrap:wrap;gap:4px}
.nav a{
  color:#fff;text-decoration:none;padding:6px 10px;border-radius:var(--radius);
  font-size:.94rem;font-weight:500;
}
.nav a:hover{background:rgba(255,255,255,.18)}

/* Hero */
.hero{
  background:linear-gradient(135deg,var(--surface) 0%,var(--surface-alt) 100%);
  border-bottom:1px solid var(--border);
  padding:36px 0 28px;
}
.hero h1{margin:0 0 6px;font-size:1.9rem;line-height:1.2;color:var(--text)}
.byline{margin:0 0 12px;color:var(--muted);font-size:.92rem}
.byline strong{color:var(--secondary)}
.hero-intro p{margin:6px 0;font-size:1.03rem}
.cta-row{margin-top:14px;display:flex;flex-wrap:wrap;gap:10px}
.cta{
  display:inline-block;padding:10px 18px;border-radius:var(--radius);
  background:var(--accent);color:#fff;text-decoration:none;font-weight:600;font-size:.95rem;
}
.cta.secondary{background:var(--secondary)}
.cta:hover{filter:brightness(.92)}

/* Content */
main{padding:24px 0 48px}
main h2{
  margin:32px 0 10px;
  padding:8px 12px;
  border-left:5px solid var(--accent);
  background:var(--surface);
  border-radius:0 var(--radius) var(--radius) 0;
  font-size:1.35rem;
  color:var(--secondary);
}
main h3{margin:20px 0 6px;font-size:1.1rem;color:var(--text)}
main p{margin:8px 0}

/* ToC */
.toc{
  background:var(--surface-alt);
  border:1px solid var(--border);
  border-radius:var(--radius);
  padding:14px 18px;
  margin:20px 0;
}
.toc strong{display:block;margin-bottom:6px;color:var(--secondary)}
.toc ol{margin:0;padding-left:22px}
.toc li{margin:3px 0}
.toc a{color:var(--text)}

/* Lists */
main ul{list-style:none;padding-left:0}
main ul li{position:relative;padding-left:24px;margin:6px 0}
main ul li::before{
  content:"\276F";position:absolute;left:0;top:0;color:var(--accent);font-weight:700;
}
main ol{list-style:none;counter-reset:step;padding-left:0}
main ol li{
  position:relative;padding-left:38px;margin:8px 0;counter-increment:step;
}
main ol li::before{
  content:counter(step);
  position:absolute;left:0;top:0;
  width:26px;height:26px;border-radius:50%;
  background:var(--primary);color:#fff;
  display:inline-flex;align-items:center;justify-content:center;
  font-size:.85rem;font-weight:700;
}

/* Tables */
.table-wrap{overflow-x:auto;margin:16px 0;border:1px solid var(--border);border-radius:var(--radius)}
table{width:100%;border-collapse:collapse;font-size:.94rem}
thead th{
  background:linear-gradient(90deg,var(--primary),var(--secondary));
  color:#fff;padding:10px 12px;text-align:left;font-weight:600;
}
tbody td{padding:9px 12px;border-top:1px solid var(--border)}
tbody tr:nth-child(even) td{background:var(--row-alt)}

/* FAQ */
details{
  border:1px solid var(--border);
  border-radius:var(--radius);
  margin:8px 0;
  background:#fff;
}
details summary{
  padding:10px 14px;cursor:pointer;font-weight:600;
  list-style:none;position:relative;padding-right:32px;color:var(--secondary);
}
details summary::-webkit-details-marker{display:none}
details summary::after{
  content:"\25BC";
  position:absolute;right:14px;top:12px;
  transition:transform .2s ease;
  color:var(--accent);font-size:.85rem;
}
details[open] summary::after{transform:rotate(180deg)}
details .a{padding:0 14px 12px}

/* Author box */
.author-box{
  display:flex;gap:16px;align-items:flex-start;
  background:linear-gradient(135deg,var(--surface),var(--surface-alt));
  border:1px solid var(--border);
  border-radius:var(--radius);
  padding:16px;margin:28px 0;
}
.author-box img{width:72px;height:72px;border-radius:50%;flex:none}
.author-box h3{margin:0 0 4px;color:var(--secondary)}
.author-box p{margin:4px 0;font-size:.94rem;color:var(--text)}

/* Figures */
figure{margin:16px 0;text-align:center}
figure svg{margin:0 auto;max-width:100%}
figcaption{color:var(--muted);font-size:.88rem;margin-top:4px}

/* Callouts */
.callout{
  background:var(--surface-alt);
  border:1px solid var(--border);
  border-left:5px solid var(--primary);
  border-radius:0 var(--radius) var(--radius) 0;
  padding:12px 14px;margin:14px 0;
}

/* Footer */
.site-footer{
  background:linear-gradient(180deg,var(--surface) 0%,var(--surface-alt) 100%);
  border-top:1px solid var(--border);
  padding:22px 0;margin-top:30px;color:var(--muted);font-size:.9rem;
}
.site-footer .container{display:flex;flex-wrap:wrap;gap:12px;justify-content:space-between;align-items:center}
.site-footer nav a{color:var(--secondary);margin-right:10px;text-decoration:none}
.site-footer nav a:hover{color:var(--accent);text-decoration:underline}

@media (min-width:700px){
  .hero h1{font-size:2.2rem}
  main h2{font-size:1.55rem}
  body{font-size:16.5px}
}
@media (min-width:980px){
  .hero{padding:52px 0 40px}
  .hero h1{font-size:2.5rem}
}

/* a11y additions */
.skip-link{position:absolute;left:-9999px;top:0;background:#0f766e;color:#fff;padding:10px 16px;border-radius:4px;z-index:1000;text-decoration:none;font-weight:700}
.skip-link:focus{left:12px;top:12px}
a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:2px}
@media (prefers-reduced-motion: reduce){*,*::before,*::after{transition-duration:.01ms !important;animation-duration:.01ms !important}}