/* =====================================================================
   APG Unterseite /lueftungssysteme/grundlagen/  ·  „Grundlagen & Technologie"
   ---------------------------------------------------------------------
   Quelle: konzept/preview-grundlagen/index.html (inline <style>-Block),
   1:1 portiert — NUR die grundlagen-spezifischen Ergänzungen. Alles, was
   bereits in hub-lueftungssysteme.css steht (--ink/--accent/... Tokens,
   .apg-hub__hero*, .apg-hub__anchor*, .apg-hub__sec*, .apg-hub__wrap*,
   .apg-hub__center, .apg-hub__split-grid/-copy/-media, .apg-hub__checks,
   .apg-hub__ph/-ph-cap), wird hier NICHT wiederholt.

   Ausgelassen (im Preview vorhanden, aber im finalen, mit Tim gezurrten
   Markup dieser Seite ungenutzt — Altlast früherer Entwurfs-Iterationen,
   siehe Session-Report): .apg-hub__mtbl (Maß-Tabelle, ersetzt durch
   .apg-hub__serien-Karten), .apg-hub__cmp/.apg-hub__pl/.apg-hub__toggle/
   .apg-hub__panel (Toggle-Vergleich, ersetzt durch das Paar-Karussell
   #g-cmpcar), .apg-hub__filt/.filt-img (ersetzt durch .apg-hub__filt2),
   .apg-hub__steps/.step/.facts/.proc/.pstep/.mini (kollidieren z.T. sogar
   mit gleichnamigen, aber anders gestalteten Klassen in
   hub-lueftungssysteme.css — Weglassen verhindert versehentliches
   Überschreiben der Hub-Seite), .bar/.logo/.apg-hub__soon-sec
   (Preview-Rahmen-Chrome, kein Seiteninhalt).

   Namespacing: .apg-hub__contact hat auf DIESER Seite ein anderes Layout
   (2-Spalten Text+Formular) als auf dem Hub (S11, Foto+Kontaktdaten) —
   selber Klassenname, andere Bedeutung. Da beide CSS-Module auf jeder
   Seite gemeinsam geladen werden (functions.php), sind die Kontakt-/
   Formular-Regeln unter .apg-hub--grundlagen skopiert, damit sie die
   Hub-Kontaktbox nicht überschreiben.
   ===================================================================== */

/* ---- Luftstrom-Animation (Gegenstrom-Prinzip, Sektion 2) ---- */
.apg-hub__anim { max-width: 940px; margin: 30px auto 10px; border-radius: 20px; overflow: hidden; border: 1px solid var(--line); background: var(--panel); box-shadow: 0 8px 26px rgba(20,26,32,.06); }
.apg-hub__anim svg { display: block; width: 100%; height: auto; }
/* Foto + Animation deckungsgleich uebereinander: Foto gibt die Box-Groesse
   vor (bestimmt Breite/Hoehe), das SVG liegt absolut darueber und deckt
   exakt dieselbe Flaeche ab (preserveAspectRatio=slice, kein Rand/Gap). */
.apg-hub__anim--photo { position: relative; }
.apg-hub__anim--photo img { display: block; width: 100%; height: auto; }
.apg-hub__anim--photo svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.apg-hub__anim-cap { max-width: 940px; margin: 0 auto; font-size: 13px; color: #8b95a0; text-align: center; }

/* ---- Wärmerückgewinnungs-Kennzahlen (3 Kacheln, Sektion 2) ---- */
.apg-hub__wrg { max-width: 880px; margin: 24px auto 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.apg-hub__wrg .k { background: var(--panel); border: 1px solid var(--line); border-radius: 14px; padding: 16px 18px; text-align: center; }
.apg-hub__wrg .k b { display: block; font-size: 26px; font-weight: 800; color: var(--ink); letter-spacing: -.02em; }
.apg-hub__wrg .k span { display: block; font-size: 12.5px; color: var(--muted); margin-top: 4px; }
@media (max-width: 720px) { .apg-hub__wrg { grid-template-columns: 1fr; } }

/* ---- Paar-Karussell (Sensorik S3, Vergleich S6, App-Steuerung S8) ---- */
.apg-hub__vcar-wrap { position: relative; max-width: 1160px; margin: 24px auto 0; padding: 0 8px; }
.apg-hub__vcar-wrap--lg { max-width: 1460px; }
.apg-hub__vcar { display: flex; gap: 24px; overflow-x: auto; scroll-snap-type: x mandatory; -webkit-overflow-scrolling: touch; padding: 26px 4px 12px; scrollbar-color: #c6cfd8 #eef1f5; }
.apg-hub__vcar::-webkit-scrollbar { height: 9px; }
.apg-hub__vcar::-webkit-scrollbar-thumb { background: #c6cfd8; border-radius: 9px; }
.apg-hub__vcar::-webkit-scrollbar-track { background: #eef1f5; border-radius: 9px; }
.apg-hub__vpair { flex: 0 0 90%; max-width: 1000px; scroll-snap-align: start; display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
@media (max-width: 760px) { .apg-hub__vpair { grid-template-columns: 1fr; flex-basis: 86%; } }
.apg-hub__vp-img { border-radius: 24px; aspect-ratio: 1/1; display: flex; align-items: center; justify-content: center; text-align: center; padding: 20px; color: var(--muted); font-weight: 600; font-size: 13px; }
.apg-hub__vp-img--photo { padding: 10px; overflow: hidden; }
.apg-hub__vp-img--photo img { width: 100%; height: 100%; object-fit: contain; border-radius: 16px; }
.apg-hub__vp-card { border-radius: 24px; padding: clamp(24px, 3vw, 42px); display: flex; flex-direction: column; justify-content: center; }
.apg-hub__vp-card--pro { outline: 2px solid var(--accent); outline-offset: -2px; }
.apg-hub__vp-card .badge { align-self: flex-start; margin-bottom: 12px; font-size: 11px; font-weight: 800; letter-spacing: .04em; text-transform: uppercase; color: var(--accent-ink); background: #fff; border-radius: 999px; padding: 4px 11px; }
.apg-hub__vp-card .badge--prob { color: #c0392b; background: #fff; }
.apg-hub__vp-card h3 { margin: 0; font-size: clamp(24px, 3vw, 32px); font-weight: 800; color: var(--ink); letter-spacing: -.01em; }
.apg-hub__vp-card .pos { font-size: 14px; color: var(--muted); margin: 6px 0 0; }
.apg-hub__vp-card .desc2 { font-size: 14.5px; color: var(--muted); line-height: 1.5; margin: 0 0 14px; }
.apg-hub__vlist { list-style: none; margin: 18px 0 0; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.apg-hub__vlist li { position: relative; padding-left: 27px; font-size: 15px; color: var(--ink-soft); line-height: 1.45; }
.apg-hub__vlist li::before { content: ""; position: absolute; left: 0; top: 2px; width: 18px; height: 18px; border-radius: 50%; background: #fff; }
.apg-hub__vlist li::after { content: "\2713"; position: absolute; left: 4px; top: 1px; font-size: 11px; font-weight: 800; color: var(--accent-ink); }
.apg-hub__vlist--x li::after { content: "\2715" !important; color: #c0392b !important; left: 3.5px !important; }
.apg-hub__vlist--x li::before { background: #fdeaea !important; }
.apg-hub__vcar-arrow { position: absolute; top: 50%; transform: translateY(-50%); z-index: 6; width: 50px; height: 50px; border-radius: 50%; border: 1px solid var(--line); background: #fff; color: var(--ink); font-size: 26px; line-height: 1; cursor: pointer; box-shadow: 0 6px 18px rgba(20,26,32,.14); display: flex; align-items: center; justify-content: center; }
.apg-hub__vcar-arrow:hover { border-color: var(--accent); color: var(--accent-ink); }
.apg-hub__vcar-arrow--prev { left: -6px; }
.apg-hub__vcar-arrow--next { right: -6px; }
.apg-hub__vcar-arrow[disabled] { opacity: .3; cursor: default; box-shadow: none; }
@media (max-width: 760px) { .apg-hub__vcar-arrow { width: 42px; height: 42px; font-size: 22px; } }

/* Große Karussell-Variante (Vergleich S6 + App-Steuerung S8): Karten 1360px, größere Typo. */
#g-appcar, #g-cmpcar { gap: 34px; padding: 30px 6px 16px; }
#g-appcar .apg-hub__vpair, #g-cmpcar .apg-hub__vpair { flex: 0 0 92%; max-width: 1360px; gap: 34px; }
#g-appcar .apg-hub__vp-img, #g-cmpcar .apg-hub__vp-img { border-radius: 34px; }
#g-appcar .apg-hub__vp-card, #g-cmpcar .apg-hub__vp-card { border-radius: 34px; padding: clamp(34px, 4.4vw, 64px); }
#g-appcar .apg-hub__vp-card h3, #g-cmpcar .apg-hub__vp-card h3 { font-size: clamp(30px, 3.8vw, 44px); line-height: 1.05; }
#g-appcar .apg-hub__vp-card .desc2 { font-size: clamp(20px, 2.3vw, 30px); line-height: 1.32; color: var(--ink-soft); margin: 16px 0 0; }
#g-cmpcar .apg-hub__vp-card .desc2 { font-size: clamp(17px, 1.8vw, 21px); line-height: 1.4; margin: 14px 0 0; }
#g-cmpcar .apg-hub__vlist { gap: 13px; margin-top: 20px; }
#g-cmpcar .apg-hub__vlist li { font-size: clamp(16px, 1.55vw, 18.5px); padding-left: 30px; }
#g-cmpcar .apg-hub__vlist li::before { width: 20px; height: 20px; }
#g-cmpcar .apg-hub__vlist li::after { font-size: 12px; left: 5px; top: 2px; }
#g-appcar .apg-hub__vp-card .badge, #g-cmpcar .apg-hub__vp-card .badge { font-size: 12px; padding: 5px 13px; margin-bottom: 14px; }
@media (max-width: 760px) {
  #g-appcar .apg-hub__vpair, #g-cmpcar .apg-hub__vpair { flex: 0 0 88%; }
  #g-appcar .apg-hub__vp-card .desc2 { font-size: 19px; }
  #g-cmpcar .apg-hub__vlist li { font-size: 15.5px; }
}

.apg-hub__gloss { max-width: 1100px; margin: 14px auto 0; font-size: 13px; color: #8b95a0; text-align: center; }

/* ---- Bauform & Maße je Serie (Sektion 4): Serie-Karten + Maßzeichnung ---- */
.apg-hub__serien { max-width: 1120px; margin: 28px auto 0; display: grid; gap: 20px; }
.apg-hub__serie-row { display: grid; grid-template-columns: .85fr 1.15fr; gap: 32px; align-items: center; background: var(--panel); border: 1px solid var(--line); border-radius: 16px; padding: 28px 32px; }
@media (max-width: 860px) { .apg-hub__serie-row { grid-template-columns: 1fr; } }
.apg-hub__serie-copy h3 { margin: 0 0 16px; font-size: 22px; font-weight: 800; color: var(--ink); }
.apg-hub__serie-specs { list-style: none; margin: 0; padding: 0; display: grid; gap: 11px; }
.apg-hub__serie-specs li { display: grid; gap: 2px; border-top: 1px solid #eef1f5; padding-top: 11px; }
.apg-hub__serie-specs li:first-child { border-top: none; padding-top: 0; }
.apg-hub__serie-specs span { font-size: 13px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); font-weight: 700; }
.apg-hub__serie-specs b { font-size: 17.5px; color: var(--ink); font-weight: 800; }
.apg-hub__serie-media img { width: 100%; height: auto; display: block; border-radius: 10px; }
.apg-hub__split-img { width: 100%; max-width: 480px; height: auto; display: block; margin: 0 auto; border-radius: 16px; }
.apg-hub__mnote { max-width: 1120px; margin: 14px auto 0; font-size: 13px; color: #8b95a0; text-align: center; }

/* ---- 360°-Spin-Viewer (Sektion 4) ---- */
.apg-hub__spin { max-width: 1120px; margin: 26px auto 0; background: var(--panel); border: 1px solid var(--line); border-radius: 20px; padding: 14px; cursor: grab; touch-action: pan-y; user-select: none; -webkit-user-select: none; }
.apg-hub__spin.dragging { cursor: grabbing; }
.apg-hub__spin img { display: block; width: 100%; height: auto; pointer-events: none; -webkit-user-drag: none; user-select: none; }
.apg-hub__spin-hint { text-align: center; font-size: 13px; color: #8b95a0; margin-top: 6px; }

/* ---- Leiser & energieeffizienter Betrieb (Sektion 5): 2 Kreis-Stats ---- */
.apg-hub__eff { max-width: 1000px; margin: 30px auto 0; display: grid; grid-template-columns: 1fr 1fr; gap: 44px; }
@media (max-width: 720px) { .apg-hub__eff { grid-template-columns: 1fr; gap: 36px; } }
.apg-hub__circle { width: 190px; height: 190px; border-radius: 50%; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; }
.apg-hub__circle .val { font-size: clamp(30px, 4vw, 42px); font-weight: 800; color: var(--ink); letter-spacing: -.02em; line-height: 1; }
.apg-hub__circle-lbl { font-size: 13.5px; color: var(--muted); margin: 12px 0 0; }
.apg-hub__eff-item h3 { margin: 6px 0 10px; font-size: 23px; font-weight: 800; color: var(--ink); }
.apg-hub__eff-item p { margin: 0; font-size: 17px; color: var(--muted); line-height: 1.55; }

/* ---- Filterung (Sektion 7): 2-Spalten, Text+2x2-Karten / Bild ---- */
.apg-hub__filt2 { max-width: 1120px; margin: 28px auto 0; display: grid; grid-template-columns: 1fr 1fr; gap: 34px; align-items: start; }
@media (max-width: 820px) { .apg-hub__filt2 { grid-template-columns: 1fr; gap: 24px; } }
.apg-hub__filt2-left h2 { font-size: clamp(27px, 3.2vw, 36px); font-weight: 800; color: var(--ink); margin: 0 0 14px; line-height: 1.12; letter-spacing: -.01em; }
.apg-hub__filt2-left .intro { font-size: 17px; color: var(--muted); line-height: 1.55; margin: 0 0 22px; max-width: none; }
.apg-hub__filt2-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 480px) { .apg-hub__filt2-cards { grid-template-columns: 1fr; } }
.apg-hub__filt2-cards .c { background: var(--panel); border: 1px solid var(--line); border-radius: 16px; padding: 22px 20px; }
.apg-hub__filt2-cards .cls { display: inline-block; font-size: 18px; font-weight: 800; color: var(--accent-ink); background: var(--tint); border-radius: 10px; padding: 5px 13px; margin-bottom: 11px; }
.apg-hub__filt2-cards h3 { margin: 0 0 6px; font-size: 15.5px; font-weight: 800; color: var(--ink); }
.apg-hub__filt2-cards p { margin: 0; font-size: 14px; color: var(--muted); line-height: 1.45; }
.apg-hub__filt2-img { width: 100%; border-radius: 20px; border: 1px solid var(--line); background: var(--panel); display: block; align-self: stretch; object-fit: cover; min-height: 100%; }

/* ---- FAQ (Sektion 9): natives <details>-Akkordeon ---- */
.apg-hub__faq { max-width: 840px; margin: 28px auto 0; }
.apg-hub__faq details { background: var(--panel); border: 1px solid var(--line); border-radius: 14px; margin-bottom: 12px; overflow: hidden; }
.apg-hub__faq summary { list-style: none; cursor: pointer; padding: 20px 24px; font-size: 17px; font-weight: 700; color: var(--ink); display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.apg-hub__faq summary::-webkit-details-marker { display: none; }
.apg-hub__faq summary::after { content: "+"; font-size: 26px; line-height: 1; color: var(--accent-ink); font-weight: 400; flex: 0 0 auto; }
.apg-hub__faq details[open] summary::after { content: "\2013"; }
.apg-hub__faq .a { padding: 0 24px 22px; font-size: 16px; color: var(--muted); line-height: 1.6; }

/* ---- Kontakt/CTA (Sektion 10): eigenes 2-Spalten-Layout mit Formular ----
   Unter .apg-hub--grundlagen skopiert (siehe Dateikopf-Kommentar) — nicht
   zu verwechseln mit .apg-hub__contact aus hub-lueftungssysteme.css. */
.apg-hub--grundlagen .apg-hub__contact { max-width: 1120px; margin: 30px auto 0; display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; background: none; border: 0; border-radius: 0; padding: 0; box-shadow: none; }
@media (max-width: 820px) { .apg-hub--grundlagen .apg-hub__contact { grid-template-columns: 1fr; gap: 32px; } }
.apg-hub--grundlagen .apg-hub__contact h2 { font-size: clamp(28px, 3.4vw, 38px); font-weight: 800; color: var(--ink); margin: 0 0 16px; line-height: 1.12; letter-spacing: -.01em; }
.apg-hub--grundlagen .apg-hub__contact .lead { font-size: 17px; color: var(--muted); line-height: 1.6; margin: 0 0 16px; }
.apg-hub--grundlagen .apg-hub__contact .cbtn { display: inline-flex; align-items: center; gap: 8px; background: var(--accent); color: #fff; font-size: 16px; font-weight: 800; text-decoration: none; padding: 14px 26px; border-radius: 999px; margin-top: 8px; }
.apg-hub--grundlagen .apg-hub__contact .cbtn:hover { background: var(--accent-ink); }
.apg-hub--grundlagen .apg-hub__form label { display: block; font-size: 14px; font-weight: 600; color: var(--ink); margin: 14px 0 7px; }
.apg-hub--grundlagen .apg-hub__form label:first-child { margin-top: 0; }
.apg-hub--grundlagen .apg-hub__form input, .apg-hub--grundlagen .apg-hub__form textarea { width: 100%; border: 1px solid #d6dde4; border-radius: 10px; padding: 14px 16px; font-family: inherit; font-size: 15px; color: var(--ink); background: #fff; box-sizing: border-box; }
.apg-hub--grundlagen .apg-hub__form input:focus, .apg-hub--grundlagen .apg-hub__form textarea:focus { outline: 2px solid var(--accent); border-color: var(--accent); }
.apg-hub--grundlagen .apg-hub__form textarea { min-height: 130px; resize: vertical; }
.apg-hub--grundlagen .apg-hub__form .sendbtn { width: 100%; margin-top: 20px; background: var(--ink); color: #fff; border: 0; border-radius: 10px; padding: 17px; font-size: 16px; font-weight: 800; font-family: inherit; cursor: pointer; }
.apg-hub--grundlagen .apg-hub__form .sendbtn:hover { background: #2a3355; }
.apg-hub--grundlagen .apg-hub__form .note { font-size: 13px; color: #8b95a0; line-height: 1.5; margin: 14px 0 0; }