/* Zahlenwerkstatt – Stylesheet */
:root{
  --ink:#363636; --muted:#6b6b6b; --line:#d7d7d7; --paper:#ffffff; --sand:#f4f1ea;
  --teal:#2dd6c1; --teal-dark:#12867a; --amber:#e8a33d;
  --serif:Georgia,"Times New Roman",serif;
  --sans:"Segoe UI",system-ui,-apple-system,Roboto,"Helvetica Neue",Arial,sans-serif;
  --wrap:1160px;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;overflow-wrap:break-word;font-family:var(--sans);font-size:17px;line-height:1.7;color:var(--ink);background:var(--paper)}
img{max-width:100%;height:auto;display:block}
a{color:var(--teal-dark);text-underline-offset:3px}
a:hover{color:var(--ink)}
h1,h2,h3{font-family:var(--serif);font-weight:400;line-height:1.25;color:var(--ink)}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 22px}
.skip{position:absolute;left:-999px}.skip:focus{left:10px;top:10px;background:#fff;padding:8px 12px;z-index:10}

/* Header */
.topbar{border-bottom:1px solid var(--line);font-size:13px;color:var(--muted)}
.topbar .wrap{display:flex;justify-content:space-between;gap:12px;padding-top:8px;padding-bottom:8px}
.topbar a{color:var(--muted)}
.brand{text-align:center;padding:30px 0 18px}
.brand a{text-decoration:none;color:var(--ink);display:inline-flex;align-items:center;gap:14px;text-align:left}
.brand .name{font-family:var(--serif);font-size:38px;letter-spacing:.5px;line-height:1.1}
.brand .claim{display:block;font-size:12.5px;letter-spacing:2px;text-transform:uppercase;color:var(--muted);margin-top:6px}
.nav{border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.nav ul{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;justify-content:center}
.nav a{display:block;padding:14px 18px;font-size:13.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;text-decoration:none;color:var(--ink)}
.nav a:hover,.nav a[aria-current]{color:var(--teal-dark)}

/* Intro */
.intro{display:grid;grid-template-columns:1.05fr 1fr;gap:56px;align-items:center;padding:64px 0}
.eyebrow{font-size:13px;letter-spacing:2px;text-transform:uppercase;color:var(--teal-dark);font-weight:700}
.intro h1{font-size:44px;margin:10px 0 18px}
.intro p{color:var(--muted);font-size:18px}
.btn{display:inline-block;background:var(--teal);color:#0d3b36;padding:12px 26px;font-size:14px;font-weight:700;letter-spacing:1px;text-transform:uppercase;text-decoration:none;border-radius:2px}
.btn:hover{background:var(--ink);color:#fff}
.btn.ghost{background:transparent;border:1px solid var(--ink);color:var(--ink);margin-left:8px}

/* Pillars */
.pillars{background:var(--sand);padding:56px 0}
.pillars .grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.pillar{background:#fff;padding:28px;border-top:3px solid var(--teal)}
.pillar h2{font-size:23px;margin:0 0 8px}
.pillar h2 a{color:var(--ink);text-decoration:none}
.pillar p{margin:0 0 12px;color:var(--muted);font-size:15.5px}
.pillar .count{font-size:13px;color:var(--teal-dark);font-weight:700}

/* Section heads */
.section-head{text-align:center;margin:64px 0 34px}
.section-head h2{font-size:32px;margin:6px 0 0}
.section-head p{color:var(--muted);margin:8px auto 0;max-width:620px}

/* Featured */
.featured{display:grid;grid-template-columns:1fr 1fr;gap:32px}
.feature{background:var(--sand);padding-bottom:4px}
.feature a.cover{display:block}
.feature .meta-box{background:#fff;margin:-50px 26px 22px;position:relative;padding:22px 24px}
.feature h3{font-size:24px;margin:6px 0 8px}
.feature h3 a{color:var(--ink);text-decoration:none}
.feature p{margin:0;color:var(--muted);font-size:15.5px}

/* Post list */
.layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:56px;margin-bottom:72px}
.card{display:grid;grid-template-columns:300px 1fr;gap:28px;padding:0 0 34px;margin:0 0 34px;border-bottom:1px solid var(--line)}
.card:last-child{border-bottom:0}
.card h3{font-size:25px;margin:6px 0 10px}
.card h3 a{color:var(--ink);text-decoration:none}
.card h3 a:hover{color:var(--teal-dark)}
.card p{margin:0 0 12px;color:var(--muted);font-size:16px}
.cat{font-size:12px;letter-spacing:1.5px;text-transform:uppercase;font-weight:700;color:var(--teal-dark);text-decoration:none}
.meta{font-size:13px;color:var(--muted)}
.meta span+span::before{content:"·";margin:0 8px}

/* Sidebar */
.sidebar .box{border:1px solid var(--line);padding:24px;margin-bottom:28px}
.sidebar h2{font-size:20px;margin:0 0 12px}
.sidebar ul{list-style:none;margin:0;padding:0}
.sidebar li{padding:8px 0;border-bottom:1px dashed var(--line);font-size:15px;line-height:1.45}
.sidebar li:last-child{border-bottom:0}
.sidebar li a{color:var(--ink);text-decoration:none}.sidebar li a:hover{color:var(--teal-dark)}
.sidebar p{font-size:15px;color:var(--muted);margin:0 0 10px}

/* Article */
.crumbs{font-size:13px;color:var(--muted);margin:28px 0 0}
.crumbs a{color:var(--muted)}
.article-head{max-width:820px;margin:18px auto 26px;text-align:center}
.article-head h1{font-size:42px;margin:10px 0 14px}
.article-head .lead{color:var(--muted);font-size:18px}
.hero-img{max-width:1000px;margin:0 auto 40px}
.article-layout{display:grid;grid-template-columns:minmax(0,720px) 260px;gap:56px;justify-content:center;margin-bottom:64px}
.prose h2{font-size:29px;margin:46px 0 12px;scroll-margin-top:20px}
.prose h3{font-size:22px;margin:32px 0 8px;scroll-margin-top:20px}
.prose p,.prose li{font-size:17.5px}
.prose ul,.prose ol{padding-left:24px}
.prose li{margin:4px 0}
.prose code{font-family:Consolas,"Courier New",monospace;font-size:.9em;background:var(--sand);padding:1px 5px;border-radius:2px;overflow-wrap:anywhere}
.prose pre{background:#22302e;color:#e8f4f2;padding:16px 18px;overflow-x:auto;border-radius:3px;font-size:15px;line-height:1.55}
.prose pre code{background:none;color:inherit;padding:0;overflow-wrap:normal}
.prose figure{margin:30px 0}
.prose figure img{border:1px solid var(--line)}
.prose figcaption{font-size:14px;color:var(--muted);margin-top:8px;text-align:center}
.prose blockquote{margin:24px 0;padding:6px 22px;border-left:3px solid var(--teal);color:var(--muted)}
.table-wrap{overflow-x:auto;margin:24px 0}
.prose table{border-collapse:collapse;width:100%;font-size:15.5px}
.prose caption{caption-side:bottom;font-size:14px;color:var(--muted);padding-top:8px;text-align:left}
.prose th,.prose td{border:1px solid var(--line);padding:9px 12px;text-align:left;vertical-align:top}
.prose thead th{background:var(--sand);font-weight:700}
.prose aside{margin:26px 0;padding:16px 20px;background:#eefbf9;border-left:4px solid var(--teal)}
.prose aside.warn{background:#fdf5e8;border-left-color:var(--amber)}
.prose aside p{margin:0;font-size:16px}
.prose kbd{border:1px solid var(--line);border-bottom-width:2px;padding:0 5px;border-radius:3px;font-size:.85em;font-family:var(--sans)}
.toc{position:sticky;top:20px;border:1px solid var(--line);padding:20px 22px;font-size:14.5px}
.toc h2{font-size:17px;margin:0 0 10px}
.toc ol{margin:0;padding-left:18px}
.toc li{margin:6px 0;line-height:1.4}
.toc a{color:var(--ink);text-decoration:none}.toc a:hover{color:var(--teal-dark)}
.method,.sources,.article-foot{border-top:1px solid var(--line);margin-top:44px;padding-top:22px}
.method h2,.sources h2{font-size:21px;margin:0 0 10px}
.method p,.sources li,.article-foot p{font-size:15.5px;color:var(--muted)}
.sources a{overflow-wrap:anywhere}
.tags span{display:inline-block;border:1px solid var(--line);padding:2px 10px;font-size:13px;margin:0 6px 6px 0;color:var(--muted);text-decoration:none}
.related{background:var(--sand);padding:52px 0}
.related .grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}
.related h3{font-size:19px;margin:8px 0 0}
.related h3 a{color:var(--ink);text-decoration:none}
.related .section-head{margin-top:0}
.page{max-width:780px;margin:0 auto 72px}
.page h1{font-size:40px;text-align:center;margin:30px 0 26px}
.notfound{text-align:center;padding:60px 0 80px}

/* Footer CTA + footer */
.cta{background:var(--teal);padding:56px 0;text-align:center;color:#0d3b36}
.cta h2{color:#0d3b36;font-size:32px;margin:0 0 10px}
.cta p{margin:0 auto 18px;max-width:600px}
.cta a.mail{color:#0d3b36;font-weight:700;font-size:20px}
footer.site{background:#2a2a2a;color:#cfcfcf;font-size:14.5px;padding:46px 0 26px}
footer.site .cols{display:grid;grid-template-columns:2fr 1fr 1fr;gap:36px}
footer.site h2{color:#fff;font-size:18px;margin:0 0 10px}
footer.site a{color:#cfcfcf}footer.site a:hover{color:var(--teal)}
footer.site ul{list-style:none;padding:0;margin:0}
footer.site li{margin:5px 0}
footer.site .legal{border-top:1px solid #444;margin-top:30px;padding-top:18px;font-size:13px;color:#9a9a9a}

@media (max-width:960px){
  .intro,.featured,.layout,.article-layout{grid-template-columns:minmax(0,1fr)}
  .pillars .grid,.related .grid{grid-template-columns:minmax(0,1fr)}
  .toc{position:static}
  .article-layout aside.side{order:-1}
  footer.site .cols{grid-template-columns:1fr}
}
@media (max-width:640px){
  body{font-size:16px}
  .brand .name{font-size:30px}
  .nav a{padding:10px 10px;font-size:12.5px}
  .intro{padding:36px 0}.intro h1,.article-head h1,.page h1{font-size:31px}
  .card{grid-template-columns:minmax(0,1fr)}
  .brand a{flex-direction:column;text-align:center;gap:8px}.brand .claim{letter-spacing:1px;font-size:11px}
  .prose h2{font-size:25px}
  .topbar .wrap{justify-content:center}.topbar .hide-s{display:none}
  .btn.ghost{margin:10px 0 0}
}