/* ==========================================================================
   heizungsgesetz.com — Design System v3  "Clarity / Modern"
   Look   : kühl, präzise, viel Weißraum, dunkler Daten-Hero, ein Indigo-Akzent
   Type   : Manrope (Display) · Space Mono (Labels/§/Daten – Signatur) · System (Body)
   ========================================================================== */

:root{
  --bg:#ffffff;
  --surface:#f6f7f9;
  --surface-2:#eef0f3;
  --ink:#0b0e14;
  --ink-2:#39414f;
  --muted:#6b7280;
  --line:#e6e8ec;
  --line-2:#d9dce2;

  --accent:#1fa24a;      /* Enerplan-Gruen */
  --accent-2:#2cc15e;
  --accent-deep:#177c39;
  --accent-tint:#e7f6ec;
  --accent-line:#c6ead2;

  --dark:#0b0e14;        /* Hero / Footer */
  --dark-2:#141824;      /* Panel auf Dunkel */
  --dark-line:rgba(255,255,255,.10);
  --on-dark:#e8eaef;
  --on-dark-dim:#9aa1ad;

  --warn:#b45309;
  --danger:#dc2626;

  --display:"Manrope","Segoe UI",system-ui,sans-serif;
  --mono:"Space Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  --body:system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;

  --wrap:1140px;
  --measure:68ch;
  --r-sm:6px; --r:9px; --r-lg:14px;
  --sh-sm:0 1px 2px rgba(11,14,20,.06);
  --sh:0 1px 2px rgba(11,14,20,.05), 0 16px 30px -20px rgba(11,14,20,.22);
}

*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto;}*{animation:none!important;transition:none!important;}}
body{margin:0;font-family:var(--body);color:var(--ink);background:var(--bg);line-height:1.65;font-size:1.02rem;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;}
img{max-width:100%;height:auto;display:block;}
svg{display:block;}
a{color:var(--accent-deep);text-underline-offset:2px;}
a:hover{color:var(--accent);}

.skip{position:absolute;left:-999px;top:0;background:var(--accent);color:#fff;padding:.7rem 1rem;z-index:100;}
.skip:focus{left:0;}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px;}

/* Layout */
.wrap{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:clamp(1.1rem,4vw,2rem);}
.section{padding-block:clamp(3rem,7vw,6rem);}
.section--tight{padding-block:clamp(2rem,4vw,3rem);}
.lede-wrap{max-width:var(--measure);}
.band-peach{background:var(--surface);}
.band-mint{background:var(--surface);}

/* Type */
h1,h2,h3,h4{font-family:var(--display);color:var(--ink);line-height:1.08;letter-spacing:-.025em;font-weight:800;}
h1{font-size:clamp(2.3rem,5.6vw,4rem);margin:0 0 .4em;}
h2{font-size:clamp(1.7rem,3.4vw,2.5rem);margin:2.6rem 0 .7rem;font-weight:800;}
h3{font-size:clamp(1.2rem,2vw,1.45rem);margin:1.8rem 0 .5rem;font-weight:700;letter-spacing:-.02em;}
h4{font-size:1.05rem;margin:1.3rem 0 .35rem;font-weight:700;}
p{margin:0 0 1.05rem;max-width:var(--measure);}
.prose li{max-width:var(--measure);margin-bottom:.45rem;}
strong{font-weight:700;}
.dim{color:var(--muted);}
.small{font-size:.875rem;}

/* Mono eyebrow / label – Signatur */
.eyebrow{font-family:var(--mono);font-weight:400;font-size:.76rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);display:inline-flex;align-items:center;gap:.55rem;margin:0 0 1.1rem;}
.eyebrow::before{content:"";width:14px;height:2px;background:var(--accent);display:inline-block;}
.para-marker{color:var(--accent);font-weight:700;}

/* Header */
.site-header{position:sticky;top:0;z-index:40;background:rgba(255,255,255,.82);backdrop-filter:saturate(1.4) blur(12px);border-bottom:1px solid var(--line);}
.nav{display:flex;align-items:center;gap:1.5rem;min-height:66px;}
.brand{display:inline-flex;align-items:center;gap:.55rem;font-family:var(--display);font-weight:800;font-size:1.1rem;color:var(--ink);text-decoration:none;letter-spacing:-.03em;}
.brand .glyph{width:30px;height:30px;flex:none;}
.brand .tld{color:var(--muted);font-weight:600;}
.nav-links{display:flex;align-items:center;gap:1.35rem;margin-left:auto;flex-wrap:wrap;}
.nav-links a{font-size:.92rem;font-weight:600;color:var(--ink-2);text-decoration:none;}
.nav-links a:hover,.nav-links a[aria-current="page"]{color:var(--ink);}
.nav-cta{background:var(--ink)!important;color:#fff!important;padding:.5rem 1rem!important;border-radius:var(--r);}
.nav-cta:hover{background:var(--accent)!important;color:#fff!important;}
@media (max-width:900px){.nav-links a:not(.nav-cta){display:none;}}

/* HERO – dunkel, datengetrieben */
.hero{position:relative;overflow:hidden;background:var(--dark);color:var(--on-dark);}
.hero::before{content:"";position:absolute;inset:0;z-index:0;background:
  radial-gradient(60% 80% at 78% 8%, rgba(34,197,94,.26), transparent 60%),
  linear-gradient(180deg, rgba(255,255,255,.02), transparent 40%);
  pointer-events:none;}
.hero::after{content:"";position:absolute;inset:0;z-index:0;opacity:.5;pointer-events:none;
  background-image:linear-gradient(var(--dark-line) 1px,transparent 1px),linear-gradient(90deg,var(--dark-line) 1px,transparent 1px);
  background-size:64px 64px;mask-image:radial-gradient(70% 60% at 70% 10%,#000,transparent 75%);}
.hero .wrap{position:relative;z-index:1;}
.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:clamp(1.6rem,4vw,3.4rem);align-items:center;padding-block:clamp(3rem,7vw,5.5rem);}
@media (max-width:920px){.hero-grid{grid-template-columns:1fr;}}
.hero .eyebrow{color:var(--on-dark-dim);}
.hero h1{color:#fff;animation:rise .55s cubic-bezier(.2,.7,.2,1) both;}
.hero h1 .hl{color:var(--accent-2);}
.hero p.lede{color:var(--on-dark-dim);font-size:clamp(1.05rem,1.7vw,1.22rem);max-width:52ch;animation:rise .55s .05s cubic-bezier(.2,.7,.2,1) both;}
@keyframes rise{from{opacity:0;transform:translateY(12px);}to{opacity:1;transform:none;}}

/* Daten-Panel im Hero */
.panel{background:var(--dark-2);border:1px solid var(--dark-line);border-radius:var(--r-lg);padding:1.4rem 1.5rem;box-shadow:0 30px 60px -30px rgba(0,0,0,.6);}
.panel-head{display:flex;align-items:center;justify-content:space-between;font-family:var(--mono);font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--on-dark-dim);padding-bottom:1rem;margin-bottom:.4rem;border-bottom:1px solid var(--dark-line);}
.panel-live{display:inline-flex;align-items:center;gap:.4rem;color:#a5f3d0;}
.status-dot{width:7px;height:7px;border-radius:50%;background:#34d399;display:inline-block;box-shadow:0 0 0 0 rgba(52,211,153,.6);animation:pulse 2.4s infinite;}
@keyframes pulse{0%{box-shadow:0 0 0 0 rgba(52,211,153,.5);}70%{box-shadow:0 0 0 7px rgba(52,211,153,0);}100%{box-shadow:0 0 0 0 rgba(52,211,153,0);}}
.prow{display:flex;align-items:baseline;justify-content:space-between;gap:1rem;padding:.72rem 0;border-bottom:1px solid var(--dark-line);}
.prow:last-child{border-bottom:none;}
.prow .k{font-family:var(--mono);font-size:.74rem;letter-spacing:.06em;text-transform:uppercase;color:var(--on-dark-dim);}
.prow .v{font-family:var(--display);font-weight:700;font-size:1.02rem;color:#fff;text-align:right;}
.prow .v.strike{color:var(--on-dark-dim);text-decoration:line-through;font-weight:600;}
.prow .v em{font-style:normal;color:var(--accent-2);}
.prow .v .arrow{color:var(--accent-2);margin:0 .25rem;}
.prow .v.good{color:#34d399;}
.panel-foot{font-family:var(--body);font-size:.76rem;color:var(--on-dark-dim);margin:.9rem 0 0;line-height:1.5;}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:.5rem;font-family:var(--display);font-weight:700;font-size:.98rem;padding:.8rem 1.4rem;border-radius:var(--r);text-decoration:none;border:1px solid transparent;cursor:pointer;transition:transform .12s,background .12s,border-color .12s,color .12s;letter-spacing:-.01em;}
.btn:hover{transform:translateY(-1px);}
.btn-primary{background:var(--accent);color:#fff;}
.btn-primary:hover{background:var(--accent-deep);color:#fff;}
.btn-pine{background:var(--ink);color:#fff;}
.btn-pine:hover{background:#20242e;color:#fff;}
.btn-ghost{border-color:var(--line-2);color:var(--ink);background:#fff;}
.btn-ghost:hover{border-color:var(--ink);}
.hero .btn-ghost{background:transparent;color:#fff;border-color:rgba(255,255,255,.28);}
.hero .btn-ghost:hover{border-color:#fff;background:rgba(255,255,255,.06);}
.btn-row{display:flex;flex-wrap:wrap;gap:.7rem;margin-top:1.5rem;}

/* TL;DR / Key facts */
.tldr{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:1.5rem 1.6rem;margin:1.8rem 0;}
.tldr h2,.tldr h3{margin-top:0;}
.tldr ul{margin-bottom:0;}
.tldr p:last-child{margin-bottom:0;}

/* Section header helper */
.sec-head{max-width:60ch;margin-bottom:2rem;}

/* Cards */
.grid{display:grid;gap:1.1rem;}
.grid-3{grid-template-columns:repeat(3,1fr);}
.grid-2{grid-template-columns:repeat(2,1fr);}
@media (max-width:840px){.grid-3{grid-template-columns:1fr 1fr;}}
@media (max-width:560px){.grid-3,.grid-2{grid-template-columns:1fr;}}
.card{position:relative;background:var(--bg);border:1px solid var(--line);border-radius:var(--r-lg);padding:1.5rem;text-decoration:none;color:var(--ink);display:block;transition:border-color .14s,box-shadow .14s,transform .14s;}
a.card:hover{border-color:var(--line-2);box-shadow:var(--sh);transform:translateY(-3px);}
.card-ico{width:40px;height:40px;border-radius:var(--r);display:grid;place-items:center;margin-bottom:1.1rem;background:var(--surface-2);color:var(--ink);border:1px solid var(--line);}
.card-ico svg{width:21px;height:21px;}
.ico-berry,.ico-honey,.ico-teal{background:var(--surface-2);color:var(--ink);}
a.card:hover .card-ico{background:var(--accent);color:#fff;border-color:var(--accent);}
.card .kicker{font-family:var(--mono);font-size:.68rem;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);}
.card h3{margin:.3rem 0 .4rem;font-size:1.2rem;font-weight:800;letter-spacing:-.02em;}
.card p{font-size:.93rem;color:var(--ink-2);margin:0;max-width:none;}
.card .more{display:inline-flex;align-items:center;gap:.3rem;margin-top:1rem;font-family:var(--display);font-weight:700;font-size:.9rem;color:var(--accent-deep);}
a.card:hover .more{color:var(--accent);}

/* Expert / Enerplan */
.expert{position:relative;background:var(--surface);border:1px solid var(--line);border-left:3px solid var(--accent);border-radius:var(--r-lg);padding:1.6rem 1.7rem;margin:2rem 0;}
.expert .tag{display:inline-flex;align-items:center;gap:.4rem;font-family:var(--mono);font-weight:400;font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--accent-deep);margin-bottom:.7rem;}
.expert h3{margin:0 0 .45rem;}
.expert p{margin-bottom:.7rem;}
.expert p:last-of-type{margin-bottom:0;}
.expert .btn{margin-top:1rem;}

/* Info boxes */
.box{border-radius:var(--r-lg);padding:1.15rem 1.35rem;margin:1.5rem 0;border:1px solid var(--line);background:var(--surface);}
.box .box-title{font-family:var(--display);font-weight:700;display:flex;align-items:center;gap:.5rem;margin-bottom:.3rem;font-size:.98rem;}
.box p:last-child,.box ul:last-child{margin-bottom:0;}
.box--info{background:var(--accent-tint);border-color:var(--accent-line);}
.box--info .box-title{color:var(--accent-deep);}
.box--warn{background:#fdf4ec;border-color:#f2ddc4;}
.box--warn .box-title{color:var(--warn);}
.box--tip{background:var(--surface);border-color:var(--line);}
.box--tip .box-title{color:var(--ink);}

/* Tables */
.table-scroll{overflow-x:auto;margin:1.7rem 0;border:1px solid var(--line);border-radius:var(--r-lg);}
table{width:100%;border-collapse:collapse;font-size:.94rem;background:var(--bg);min-width:520px;}
caption{text-align:left;font-family:var(--mono);font-size:.74rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);padding:1rem 1.1rem .5rem;}
thead th{background:var(--surface);color:var(--ink);text-align:left;font-family:var(--display);font-weight:700;font-size:.85rem;padding:.75rem 1rem;border-bottom:1px solid var(--line-2);}
tbody td,tbody th{padding:.78rem 1rem;border-top:1px solid var(--line);vertical-align:top;text-align:left;}
tbody th{font-weight:700;color:var(--ink);}
tbody tr:hover{background:var(--surface);}
.tabnum{font-family:var(--mono);font-size:.9em;font-variant-numeric:tabular-nums;}
.pos{color:var(--accent-deep);font-weight:700;}
.neg{color:var(--danger);font-weight:700;}

/* Checklist */
.checklist{list-style:none;padding:0;margin:1.3rem 0;}
.checklist li{position:relative;padding-left:2rem;margin-bottom:.75rem;max-width:var(--measure);}
.checklist li::before{content:"";position:absolute;left:0;top:.15em;width:1.3rem;height:1.3rem;border-radius:var(--r-sm);background:var(--accent-tint);border:1px solid var(--accent-line);}
.checklist li::after{content:"";position:absolute;left:.42rem;top:.3em;width:.38rem;height:.7rem;border:solid var(--accent);border-width:0 2px 2px 0;transform:rotate(42deg);}

/* FAQ */
.faq{margin:1.5rem 0;}
.faq details{border:1px solid var(--line);border-radius:var(--r);margin-bottom:.6rem;background:var(--bg);overflow:hidden;}
.faq summary{cursor:pointer;list-style:none;padding:1.05rem 1.2rem;font-family:var(--display);font-weight:700;font-size:1.03rem;display:flex;justify-content:space-between;gap:1rem;align-items:center;color:var(--ink);letter-spacing:-.01em;}
.faq summary::-webkit-details-marker{display:none;}
.faq summary::after{content:"+";color:var(--muted);font-family:var(--mono);font-size:1.15rem;line-height:1;flex:none;transition:transform .2s,color .2s;}
.faq details[open] summary::after{content:"\2212";color:var(--accent);}
.faq details[open] summary{color:var(--ink);}
.faq .answer{padding:0 1.2rem 1.15rem;}
.faq .answer p:last-child{margin-bottom:0;}

/* Breadcrumb */
.crumb{font-family:var(--mono);font-size:.75rem;letter-spacing:.04em;color:var(--muted);padding-block:1.1rem;}
.crumb a{color:var(--muted);text-decoration:none;}
.crumb a:hover{color:var(--ink);}
.crumb span[aria-current]{color:var(--ink-2);}

/* TOC */
.toc{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:1.3rem 1.5rem;margin:1.8rem 0;}
.toc strong{font-family:var(--mono);font-weight:700;font-size:.74rem;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);display:block;margin-bottom:.7rem;}
.toc ol{margin:0;padding-left:1.2rem;columns:2;column-gap:2.4rem;}
.toc li{margin-bottom:.4rem;}
.toc a{text-decoration:none;color:var(--ink-2);}
.toc a:hover{color:var(--accent);}
@media (max-width:640px){.toc ol{columns:1;}}

/* Related */
.related{display:grid;grid-template-columns:repeat(3,1fr);gap:.8rem;margin:1.7rem 0;}
@media (max-width:720px){.related{grid-template-columns:1fr;}}
.related a{background:var(--bg);border:1px solid var(--line);border-radius:var(--r);padding:.85rem 1.1rem;text-decoration:none;font-weight:700;font-size:.92rem;color:var(--ink);display:flex;align-items:center;gap:.5rem;transition:border-color .14s,color .14s;}
.related a:hover{border-color:var(--accent);color:var(--accent-deep);}

/* CTA band – dunkel */
.cta-band{position:relative;overflow:hidden;background:var(--dark);color:#fff;border-radius:var(--r-lg);padding:clamp(2.2rem,5vw,3.4rem);margin:2.8rem 0;text-align:center;}
.cta-band::before{content:"";position:absolute;inset:0;background:radial-gradient(60% 100% at 50% 0%,rgba(34,197,94,.32),transparent 60%);pointer-events:none;}
.cta-band h2{color:#fff;margin-top:0;position:relative;}
.cta-band p{color:var(--on-dark-dim);max-width:54ch;margin-inline:auto;position:relative;}
.cta-band .btn-row{justify-content:center;position:relative;}
.cta-band .btn-primary{background:#fff;color:var(--ink);}
.cta-band .btn-primary:hover{background:var(--accent);color:#fff;}

/* Stats */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:1rem;margin:1.8rem 0;}
@media (max-width:720px){.stats{grid-template-columns:1fr 1fr;}}
.stat{background:var(--bg);border:1px solid var(--line);border-radius:var(--r-lg);padding:1.4rem 1.3rem;}
.stat .n{font-family:var(--display);font-weight:800;font-size:2.15rem;color:var(--ink);letter-spacing:-.04em;font-variant-numeric:tabular-nums;}
.stat:nth-child(1) .n{color:var(--accent);}
.stat .l{font-family:var(--mono);font-size:.72rem;letter-spacing:.04em;text-transform:uppercase;color:var(--muted);margin-top:.35rem;line-height:1.4;}

/* Footer */
.site-footer{background:var(--dark);color:var(--on-dark-dim);margin-top:4rem;border-top:1px solid var(--dark-line);}
.site-footer .wrap{padding-block:3.2rem 1.8rem;}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:1.8rem;}
@media (max-width:820px){.foot-grid{grid-template-columns:1fr 1fr;}}
@media (max-width:520px){.foot-grid{grid-template-columns:1fr;}}
.site-footer h4{color:#fff;font-family:var(--mono);font-weight:400;font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;margin:0 0 .9rem;}
.site-footer a{color:var(--on-dark-dim);text-decoration:none;display:block;padding:.24rem 0;font-size:.92rem;}
.site-footer a:hover{color:#fff;}
.site-footer .brand{color:#fff;margin-bottom:.7rem;}
.site-footer .brand .tld{color:var(--on-dark-dim);}
.foot-legal{border-top:1px solid var(--dark-line);margin-top:2rem;padding-top:1.3rem;font-size:.82rem;color:var(--on-dark-dim);display:flex;justify-content:space-between;flex-wrap:wrap;gap:.6rem;}
.foot-legal a{display:inline;color:#c7cad2;}

/* Utilities */
.mt0{margin-top:0;}.mb0{margin-bottom:0;}.center{text-align:center;}
.pill{display:inline-block;font-family:var(--mono);font-weight:400;font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;padding:.24rem .55rem;border-radius:var(--r-sm);border:1px solid var(--line-2);color:var(--muted);}
.pill--new{background:var(--accent-tint);color:var(--accent-deep);border-color:var(--accent-line);}
.pill--law{background:var(--surface-2);color:var(--ink-2);}
hr.rule{border:none;border-top:1px solid var(--line);margin:2.4rem 0;}