/* RDHx — arkusz stylów (PL, rysowany schemat z animowaną wodą) */
:root{
  --bg:#f4f6f8; --panel:#ffffff; --ink:#0f172a; --muted:#5b6b7f; --line:#dfe5ec;
  --accent:#0284c7; --warm:#ea580c; --warm-bg:#fff2e8; --cool:#0891b2; --cool-bg:#e6f7fb;
  --idle:#c2ccd8; --backup:#7c3aed; --future:#94a3b8;
  --pipe:#d4deea; --node:#ffffff; --node-line:#c4cfdb; --accent-bg:#fef3e2;
  --rack:#334155; --rack2:#1e293b; --srv:#e8edf3; --metal:#9fb0c3; --metal2:#7d8fa6;
  --radius:14px; --maxw:1100px;
  --sans:system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --mono:ui-monospace,"SF Mono",Menlo,Consolas,monospace;
}
@media (prefers-color-scheme:dark){
  :root{
    --bg:#0b1119; --panel:#131c27; --ink:#e6edf5; --muted:#93a2b5; --line:#243244;
    --accent:#38bdf8; --warm:#fb923c; --warm-bg:#2a1a0e; --cool:#22d3ee; --cool-bg:#0c2630;
    --idle:#3a4a5e; --backup:#a78bfa; --future:#64748b;
    --pipe:#2a3b4f; --node:#182231; --node-line:#31435a; --accent-bg:#2a2012;
    --rack:#475569; --rack2:#0f172a; --srv:#233043; --metal:#5c6f86; --metal2:#7d8fa6;
  }
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);line-height:1.6;-webkit-text-size-adjust:100%}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}
h1,h2,h3{line-height:1.25}
a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}

.site-header{background:linear-gradient(180deg,var(--panel),transparent);border-bottom:1px solid var(--line);padding:34px 0 26px}
.site-header h1{margin:0 0 10px;font-size:clamp(1.4rem,3.4vw,2.1rem);letter-spacing:-.02em}
.site-header .arrow{color:var(--warm)}
.btn3d{display:inline-block;background:var(--accent);color:#fff;font-weight:700;
  padding:10px 16px;border-radius:10px;text-decoration:none}
.btn3d:hover{filter:brightness(1.12);text-decoration:none}
.lede{margin:0;max-width:72ch;color:var(--muted);font-size:1.02rem}

main{padding:26px 0 60px}
.panel{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:22px 24px;margin:18px 0}
.panel h2{margin:0 0 12px;font-size:1.28rem;letter-spacing:-.01em}
.panel h3{margin:16px 0 6px;font-size:1.02rem}
.panel p{margin:.5em 0}

/* --- controls --- */
.controls{display:flex;flex-wrap:wrap;gap:26px;align-items:flex-start;margin:4px 0 18px}
.control{display:flex;flex-direction:column;gap:8px}
.control-slider{flex:1;min-width:320px}
.control-label{font-size:.74rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);font-weight:600}
.control-label b{color:var(--warm);font-family:var(--mono);font-size:1.05rem;letter-spacing:0}
.segmented{display:inline-flex;background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:3px}
.segmented button{appearance:none;border:0;background:transparent;color:var(--muted);font:inherit;font-weight:600;padding:8px 16px;border-radius:8px;cursor:pointer;transition:.15s}
.segmented button:hover{color:var(--ink)}
.segmented button.is-on{background:var(--panel);color:var(--ink);box-shadow:0 1px 3px rgba(0,0,0,.12)}
#season-ctl button.is-on{color:var(--warm)}
#season-ctl button[data-season="summer"].is-on{color:var(--cool)}

/* slider */
#load-slider{-webkit-appearance:none;appearance:none;width:100%;height:8px;border-radius:6px;
  background:linear-gradient(90deg,var(--accent),var(--warm));outline:none;margin:2px 0 0}
#load-slider::-webkit-slider-thumb{-webkit-appearance:none;width:22px;height:22px;border-radius:50%;
  background:var(--panel);border:3px solid var(--warm);box-shadow:0 1px 4px rgba(0,0,0,.3);cursor:pointer}
#load-slider::-moz-range-thumb{width:20px;height:20px;border-radius:50%;background:var(--panel);border:3px solid var(--warm);cursor:pointer}
.scale{position:relative;height:34px;margin-top:2px;font-size:.7rem;color:var(--muted)}
.scale .tick{position:absolute;transform:translateX(-50%);text-align:center;white-space:nowrap;line-height:1.15}
.scale .tick small{display:block;font-size:.62rem;opacity:.75}
.scale .tick.now{color:var(--warm);font-weight:700}
.scale .tick.goal{transform:translateX(-90%)}
.scale .tick.est{opacity:.7}

/* --- energy balance --- */
.balance{display:grid;grid-template-columns:repeat(3,1fr);gap:14px 18px;align-items:end;margin:6px 0 4px}
.balance-fig{display:flex;flex-direction:column;gap:2px}
.fig-label{font-size:.74rem;color:var(--muted);text-transform:uppercase;letter-spacing:.04em;font-weight:600}
.fig-num{font-family:var(--mono);font-size:1.9rem;font-weight:700;line-height:1}
.fig-unit{font-size:.72rem;color:var(--muted)}
.balance-fig.reuse .fig-num{color:var(--warm)}
.balance-fig.reject .fig-num{color:var(--cool)}
.balance-bar{grid-column:1/-1;display:flex;height:14px;border-radius:8px;overflow:hidden;background:var(--idle);margin-top:2px}
.bar-reuse{background:var(--warm);transition:width .35s ease}
.bar-reject{background:var(--cool);transition:width .35s ease}
.balance-note{grid-column:1/-1;margin:2px 0 0;font-size:.88rem;color:var(--muted)}

/* --- diagram --- */
.diagram-scroll{overflow-x:auto;margin:14px -6px 0;padding:2px 6px}
#sys{display:block;width:100%;min-width:860px;height:auto}
.caption{font-size:.86rem;color:var(--muted);margin-top:10px}

/* text */
#sys .nt{fill:var(--ink);font:600 14px var(--sans)}
#sys .ns{fill:var(--muted);font:400 11.5px var(--sans)}
#sys .ns.strong{fill:var(--ink);font-weight:700;font-family:var(--mono);font-size:12.5px}
#sys .edge{fill:var(--muted);font:500 10.5px var(--mono)}
#sys .warm-t{fill:var(--warm)} #sys .fut-t{fill:var(--future)}

/* gradients (stops set here so CSS vars resolve) */
#sys #gTank stop:first-child{stop-color:var(--warm)}
#sys #gTank stop:last-child{stop-color:var(--accent)}
#sys #air path{stroke:var(--warm);fill:none}

/* pipes + water */
@keyframes flow{to{stroke-dashoffset:-28}}
@keyframes spin{to{transform:rotate(360deg)}}
#sys .pipe{fill:none;stroke:var(--pipe);stroke-width:11;stroke-linecap:round}
#sys .water{fill:none;stroke:var(--accent);stroke-width:5.5;stroke-linecap:round;stroke-dasharray:16 12;animation:flow 1s linear infinite}
#sys .water.branch{stroke:var(--idle);animation:none;opacity:.5}
#sys .water.branch.both{stroke:var(--accent);animation:flow 1s linear infinite;opacity:1}
#sys.season-winter #w-ufh{stroke:var(--warm);animation:flow 1s linear infinite;opacity:1}
#sys.season-summer #w-dry{stroke:var(--cool);animation:flow 1s linear infinite;opacity:1}
#sys .pipe.gas{stroke:color-mix(in srgb,var(--backup) 30%,var(--pipe));stroke-width:8}
#sys .water.gasw{stroke:var(--backup);stroke-width:4;stroke-dasharray:5 8;animation:flow 1.5s linear infinite;opacity:.85}
#sys .pipe.fut{stroke:var(--future);stroke-width:5;stroke-dasharray:2 7;opacity:.55}
#sys .airflow{fill:none;stroke:var(--warm);stroke-width:2;stroke-dasharray:4 4;opacity:.8}

/* rack */
#sys .rack-frame{fill:var(--rack2);stroke:var(--rack);stroke-width:2}
#sys .rack-inner{fill:var(--rack)}
#sys .srv rect{fill:var(--srv);stroke:var(--metal2);stroke-width:1}
#sys .srv line{stroke:var(--metal2);stroke-width:1.4;opacity:.6}
#sys .srv .led{stroke:none}
#sys .srv .led.g{fill:#22c55e} #sys .srv .led.b{fill:#38bdf8}

/* coils + fans */
#sys .coil{fill:var(--accent-bg);stroke:var(--metal2);stroke-width:1.4}
#sys .fins line{stroke:var(--accent);stroke-width:1.4;opacity:.45}
#sys .fan-ring{fill:var(--node);stroke:var(--metal2);stroke-width:1.6}
#sys .fan-spin{transform-box:fill-box;transform-origin:center;animation:spin 3.4s linear infinite}
#sys .fan-spin path{fill:var(--metal)}
#sys .fan-hub{fill:var(--rack)}
#sys .dc-fan .fan-spin{animation-duration:2.2s;animation-play-state:paused}
#sys.season-summer .dc-fan .fan-spin{animation-play-state:running}

/* plate HX */
#sys .hx-body{fill:var(--node);stroke:var(--node-line);stroke-width:1.6}
#sys .plates line{stroke:var(--metal2);stroke-width:2;opacity:.7}

/* buffer tank */
#sys .tank-body{fill:var(--node);stroke:var(--node-line);stroke-width:1.8}
#sys .tank-fill{fill:url(#gTank);opacity:.85}
#sys .tank-top{fill:var(--warm-bg);stroke:var(--node-line);stroke-width:1.8}
#sys .tank-rim{fill:none;stroke:var(--warm);stroke-width:1.6;opacity:.6}
#sys .tank-mark{stroke:var(--panel);stroke-width:1;opacity:.5}

/* valve */
#sys .valve{fill:var(--node);stroke:var(--metal2);stroke-width:1.8}
#sys .valve-ports{stroke:var(--metal2);stroke-width:3;fill:none;stroke-linecap:round}
#sys .valve-stem{fill:var(--metal2)}

/* underfloor heating */
#sys .house-roof{fill:none;stroke:var(--node-line);stroke-width:2.4;stroke-linejoin:round}
#sys .house-floor{fill:var(--bg);stroke:var(--node-line);stroke-width:1.6}
#sys .ufh-loop{fill:none;stroke:var(--idle);stroke-width:2.4;stroke-linecap:round}
#sys.season-winter #node-ufh .ufh-loop{stroke:var(--warm)}

/* DHW + sun */
#sys .dhw-tank{fill:var(--node);stroke:var(--node-line);stroke-width:1.8}
#sys .dhw-pipe{fill:none;stroke:var(--metal2);stroke-width:2}
#sys .dhw-tap{fill:var(--accent)}
#sys .sun{fill:url(#gSun)}
#sys .sun-rays line{stroke:#f59e0b;stroke-width:2;stroke-linecap:round}

/* dry cooler */
#sys .dc-body{fill:var(--node);stroke:var(--node-line);stroke-width:1.8}
#sys .dc-fin{stroke:var(--metal2);stroke-width:1.4;opacity:.6}
#sys.season-summer #node-dry .dc-body{stroke:var(--cool);stroke-width:2.4}

/* boiler + ashp */
#sys .boiler{fill:var(--node);stroke:var(--backup);stroke-width:1.8;stroke-dasharray:5 4}
#sys .flame{fill:var(--warm)}
#sys .ashp{fill:none;stroke:var(--future);stroke-width:1.8;stroke-dasharray:2 5}
#sys .fut-ring{fill:none;stroke:var(--future);stroke-width:1.6}
#sys .fut-blade{fill:none;stroke:var(--future);stroke-width:1.2;opacity:.7}

/* legend */
#sys .legend text{fill:var(--muted);font:500 11px var(--sans)}
.lg-warm{fill:var(--warm)} .lg-cool{fill:var(--cool)} .lg-idle{fill:var(--idle)}
.lg-gas{stroke:var(--backup);stroke-width:3.4;stroke-dasharray:5 4} .lg-fut{stroke:var(--future);stroke-width:3;stroke-dasharray:2 5}

@media (prefers-reduced-motion:reduce){#sys *{animation:none!important}}

/* tables */
.table-scroll{overflow-x:auto}
table{border-collapse:collapse;width:100%;font-size:.94rem}
th,td{text-align:left;padding:9px 12px;border-bottom:1px solid var(--line)}
th{font-size:.74rem;text-transform:uppercase;letter-spacing:.04em;color:var(--muted)}
td.num,th.num{text-align:right;font-family:var(--mono);white-space:nowrap}
td.meas{color:var(--warm);font-weight:700}
tr.total td{font-weight:700;border-top:2px solid var(--line)}
tr.ghost-row td{color:var(--muted);font-style:italic}

/* layout helpers */
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:22px}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:14px;margin-top:6px}
.card{position:relative;background:var(--bg);border:1px solid var(--line);border-radius:12px;padding:14px 16px}
.card.chosen{border-color:var(--warm);background:var(--warm-bg)}
.chosen-badge{position:absolute;top:-10px;right:12px;background:var(--warm);color:#fff;font-size:.68rem;font-weight:700;padding:2px 10px;border-radius:999px}
.card h3{margin:0 0 6px;font-size:.98rem}
.card .spec{font-family:var(--mono);font-size:.78rem;color:var(--muted);margin:0 0 8px}
.pill{display:inline-block;background:var(--accent-bg);color:var(--warm);font-size:.7rem;font-weight:700;padding:2px 8px;border-radius:999px}
.speclist{margin:.4em 0;padding-left:1.1em}.speclist li{margin:.35em 0}
.linkline{margin-top:8px}
.warn{border-left:3px solid var(--warm);padding-left:12px;background:var(--warm-bg);border-radius:0 8px 8px 0;padding-top:8px;padding-bottom:8px}
.tip{border-left:3px solid var(--accent);padding-left:12px}
.season{border-radius:12px;padding:14px 16px}
.winter-card{background:var(--warm-bg);border:1px solid var(--warm)}
.summer-card{background:var(--cool-bg);border:1px solid var(--cool)}
.season h3{margin:0 0 6px}
.mini{font-size:.86rem;color:var(--muted)}
.verdict{background:var(--bg);border:1px solid var(--line);border-radius:12px;padding:14px 16px}

.site-footer{border-top:1px solid var(--line);padding:22px 0;color:var(--muted);font-size:.86rem}
.site-footer p{margin:0;max-width:74ch}

@media (max-width:720px){
  .grid2{grid-template-columns:1fr}
  .balance{grid-template-columns:1fr 1fr}
  .fig-num{font-size:1.5rem}
  .control-slider{min-width:100%}
}