/* =========================================================================
   Chauffage Montereau — feuille de style unique
   Sommaire :
   1. Variables
   2. Reset
   3. Typographie
   4. Layout / utilitaires
   5. Bandeau utilitaire + en-tête + navigation
   6. Fil d'Ariane
   7. Hero
   8. Boutons
   9. Bandeau badges
   10. Cartes équipements / grilles
   11. Bandeau stats
   12. Aides / deux colonnes
   13. Contenu éditorial (prose)
   14. Tableaux
   15. FAQ / accordéon
   16. Étapes
   17. Section locale (sombre)
   18. Encarts / notices
   19. Formulaire de devis
   20. CTA
   21. Liens connexes
   22. Pied de page
   23. Responsive
   ====================================================================== */

/* 1. Variables ----------------------------------------------------------- */
:root {
  --c-bg:        #ffffff;
  --c-bg-soft:   #F5F7F9;
  --c-bg-alt:    #EAEEF1;
  --c-ink:       #1C2530;
  --c-ink-soft:  #4A5763;
  --c-muted:     #5D6B79;
  --c-line:      #E3E8ED;
  --c-primary:   #B84E0C;   /* orange (assombri pour AA) — boutons d'action */
  --c-primary-d: #96400A;
  --c-primary-bright: #F36F21; /* orange vif — décoratif uniquement, jamais en texte ni fond de texte */
  --c-blue:      #0B4F7A;   /* bleu — liens, icônes, repères secondaires */
  --c-blue-d:    #083A5A;
  --c-navy:      #0B2740;   /* fond sombre : en-tête utilitaire, hero, section locale */
  --c-navy-deep: #081D30;   /* pied de page */
  --c-ok-bg:     #EAF1F6;
  --c-ok-line:   #CBDCE8;
  --c-warn-bg:   #FDF3EA;
  --c-warn-line: #F0C89A;

  --radius:   0px;
  --radius-s: 0px;
  --wrap:     1180px;
  --wrap-narrow: 760px;
  --hero-bevel: clamp(0px, 0vw, 0px);

  --font: 'Source Sans 3', system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-h: 'Archivo', system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* 2. Reset -------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--c-ink);
  background: var(--c-bg);
  line-height: 1.6;
  font-size: 1.0625rem;
  text-rendering: optimizeLegibility;
}
img, svg, video { max-width: 100%; height: auto; display: block; }
a { color: var(--c-blue); text-underline-offset: 2px; }
a:hover { color: var(--c-primary); }
button { font: inherit; cursor: pointer; }

/* 3. Typographie ------------------------------------------------------- */
h1, h2, h3, h4 { font-family: var(--font-h); line-height: 1.15; font-weight: 700; color: var(--c-navy); letter-spacing: -.015em; }
h1 { font-size: clamp(1.9rem, 1.3rem + 3vw, 2.9rem); font-weight: 800; }
h2 { font-size: clamp(1.4rem, 1.15rem + 1.3vw, 1.9rem); margin-top: 2.2em; }
h3 { font-size: 1.2rem; margin-top: 1.6em; font-weight: 700; }
p, ul, ol { margin-top: 1em; }
strong { color: var(--c-ink); }
small { font-size: .8125rem; }

.visually-hidden {
  position: absolute !important; width: 1px; height: 1px; padding: 0;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 100;
  background: var(--c-navy); color: #fff; padding: .6rem 1rem;
}
.skip-link:focus { left: 0; }
:focus-visible { outline: 3px solid var(--c-blue); outline-offset: 2px; }

/* 4. Layout ---------------------------------------------------------- */
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: 20px; }
.section { padding-block: clamp(2.5rem, 1.5rem + 4vw, 4.5rem); }
.section--soft { background: var(--c-bg-soft); }
.section--warm { background: var(--c-warn-bg); }
.lede { font-size: 1.15rem; color: var(--c-muted); }
.center { text-align: center; }
.eyebrow { font-size: .85rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--c-primary); margin: 0 0 .5rem; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 1.2rem 1.8rem; flex-wrap: wrap; margin-bottom: 2rem; }
.section-head .lede { margin: 0; max-width: 380px; }
.section-head h2 { margin-top: 0; }

/* 5. Bandeau utilitaire + en-tête + navigation --------------------- */
.topbar { background: var(--c-navy); color: #cfe0ec; font-size: .85rem; }
.topbar__inner {
  display: flex; flex-wrap: wrap; gap: .4rem 1.2rem; align-items: center;
  justify-content: space-between; padding-block: .5rem;
}
.topbar__left { display: flex; flex-wrap: wrap; gap: .3rem 1.2rem; }
.topbar__strong { color: #fff; font-weight: 600; }

.site-header {
  position: sticky; top: 0; z-index: 50;
  background: #fff; border-bottom: 1px solid var(--c-line);
}
.site-header__inner { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem; min-height: 68px; }
.brand { display: flex; align-items: center; gap: .7rem; text-decoration: none; color: var(--c-ink); }
.brand__mark {
  width: 38px; height: 38px; flex: none; background: var(--c-blue); color: #fff;
  display: grid; place-items: center; font-family: var(--font-h); font-weight: 800; font-size: 1.05rem;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.2; }
.brand__text strong { font-family: var(--font-h); font-weight: 700; font-size: 1.05rem; color: var(--c-navy); }
.brand__text small { color: var(--c-muted); font-size: .75rem; letter-spacing: .04em; text-transform: uppercase; }

.nav-toggle {
  margin-left: auto; width: 44px; height: 44px; border: 1px solid var(--c-line);
  background: #fff; display: grid; place-items: center;
}
.nav-toggle__bar, .nav-toggle__bar::before, .nav-toggle__bar::after {
  content: ""; display: block; width: 20px; height: 2px; background: var(--c-ink); transition: transform .2s, opacity .2s;
}
.nav-toggle__bar::before { transform: translateY(-6px); }
.nav-toggle__bar::after  { transform: translateY(4px); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar::before { transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar::after  { transform: rotate(-45deg); }

.site-nav { display: none; }
.site-nav__list { list-style: none; padding: 0; margin: 0; }
.site-nav__list a {
  display: block; padding: .8rem .25rem; text-decoration: none; color: var(--c-ink);
  border-bottom: 1px solid var(--c-line); font-weight: 600;
}
.site-nav__list a[aria-current="page"] { color: var(--c-primary); }
.site-nav__cta { margin: .9rem 0 .3rem; text-align: center; }

/* 6. Fil d'Ariane -------------------------------------------------- */
.breadcrumbs { background: var(--c-bg-soft); border-bottom: 1px solid var(--c-line); font-size: .875rem; }
.breadcrumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: .35rem; padding: .6rem 0; margin: 0; }
.breadcrumbs li:not(:last-child)::after { content: "›"; margin-left: .35rem; color: var(--c-muted); }
.breadcrumbs [aria-current="page"] { color: var(--c-muted); }

/* 7. Hero -------------------------------------------------------- */
.hero { background: var(--c-navy); color: #fff; }
.hero__grid {
  display: grid; gap: 2.5rem; align-items: center;
  padding-block: clamp(2.2rem, 1.3rem + 3vw, 4rem);
}
.hero__content { max-width: var(--wrap-narrow); }
.hero__eyebrow {
  display: inline-block; border: 1px solid #3d6d93; color: #9fc6e0;
  font-size: .8rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase;
  padding: .4rem .8rem; margin-bottom: 1.2rem;
}
.hero h1 { color: #fff; margin-bottom: .6rem; }
.hero .lede { color: #c6d8e5; margin-bottom: 1.6rem; }
.hero__actions { display: flex; flex-wrap: wrap; gap: .8rem; align-items: center; }
.hero__trust { margin-top: 1.4rem; font-size: .9rem; color: #9fb9cd; }
.hero__trust strong { color: #fff; }

.hero__figure { margin: 0; position: relative; }
.hero__figure picture { display: block; position: relative; }
.hero__figure img {
  display: block; width: 100%; height: auto; aspect-ratio: 16 / 10;
  object-fit: cover; object-position: 58% 52%;
}
.hero__figure::before {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(155deg, rgba(11,39,64,.25), transparent 55%);
  pointer-events: none;
}
.hero__figure figcaption {
  margin-top: .55rem; font-size: .75rem; color: #9fb9cd;
}
.hero__figure figcaption a { color: #cfe0ec; }

/* 8. Boutons --------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  padding: .75rem 1.35rem; font-weight: 700; text-decoration: none;
  border: 1.5px solid transparent; transition: background .15s, border-color .15s, transform .05s;
  line-height: 1.2; font-family: var(--font-h);
}
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--c-primary); color: #fff; }
.btn--primary:hover { background: var(--c-primary-d); color: #fff; }
.btn--ghost { border-color: #4a7b9f; color: #fff; background: transparent; }
.btn--ghost:hover { border-color: #fff; color: #fff; }
.btn--dark { background: var(--c-navy); color: #fff; }
.btn--dark:hover { background: var(--c-navy-deep); color: #fff; }
.btn--lg { padding: 1rem 1.8rem; font-size: 1.05rem; }

/* 9. Bandeau badges -------------------------------------------- */
.badges { background: var(--c-bg-soft); border-bottom: 1px solid var(--c-line); }
.badges__inner {
  display: flex; flex-wrap: wrap; align-items: center; gap: .5rem;
  justify-content: space-between; padding-block: 1.3rem;
}
.badges__label { font-size: .85rem; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; color: var(--c-muted); }
.badge {
  display: inline-flex; align-items: center; gap: .5rem;
  border: 1px solid var(--c-line); color: var(--c-ink-soft); font-size: .85rem; font-weight: 600;
  padding: .5rem 1rem; background: #fff;
}
.badge__icon { width: 18px; height: 18px; flex: none; color: var(--c-blue); }

/* 10. Cartes équipements / grilles ------------------------------ */
.grid { display: grid; gap: 1rem; }
.grid--2 { grid-template-columns: 1fr; }
.grid--3 { grid-template-columns: 1fr; }
.grid--4 { grid-template-columns: 1fr 1fr; }

.link-card {
  display: block; border: 1px solid var(--c-line);
  padding: 1.1rem 1.25rem; text-decoration: none; color: var(--c-ink);
  transition: border-color .15s, background .15s;
}
.link-card:hover { border-color: var(--c-blue); background: var(--c-bg-soft); color: var(--c-ink); }
.link-card strong { display: block; font-family: var(--font-h); font-size: 1.1rem; font-weight: 700; color: var(--c-navy); }
.link-card span { color: var(--c-muted); font-size: .95rem; }

.grid-cards { display: grid; grid-template-columns: 1fr; gap: 1px; background: var(--c-line); border: 1px solid var(--c-line); }
.card { background: #fff; padding: 1.6rem 1.5rem 1.4rem; display: block; color: inherit; text-decoration: none; }
.card:hover { background: var(--c-bg-soft); color: inherit; }
.card__icon {
  display: grid; place-items: center; width: 46px; height: 46px;
  background: var(--c-ok-bg); border-bottom: 3px solid var(--c-blue); color: var(--c-blue);
  margin-bottom: 1.1rem;
}
.card__icon svg { width: 26px; height: 26px; }
.card__title { display: block; font-family: var(--font-h); font-weight: 700; font-size: 1.2rem; color: var(--c-navy); margin-bottom: .5rem; }
.card__text { display: block; color: var(--c-ink-soft); font-size: .98rem; line-height: 1.5; margin-bottom: 1rem; }
.card__foot { display: flex; align-items: center; justify-content: space-between; gap: .75rem; border-top: 1px solid var(--c-bg-alt); padding-top: .75rem; font-size: .92rem; color: var(--c-muted); }
.card__foot strong { color: var(--c-navy); }
.card__link { color: var(--c-primary); font-weight: 700; }

/* 11. Bandeau stats ----------------------------------------- */
.stats { background: var(--c-blue); color: #fff; }
.stats__inner { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.8rem 2rem; padding-block: 2.6rem; }
.stat__val { display: block; font-family: var(--font-h); font-weight: 800; font-size: clamp(1.9rem, 1.5rem + 1.6vw, 2.6rem); line-height: 1; margin-bottom: .5rem; }
.stat__lab { display: block; color: #bcd8ea; font-size: .95rem; line-height: 1.45; }

/* 12. Aides / deux colonnes ---------------------------------- */
.two-col { display: grid; grid-template-columns: 1fr; gap: 2.2rem; align-items: start; }
.aides-list { display: grid; gap: 1px; background: var(--c-line); border: 1px solid var(--c-line); margin: 1.2rem 0 0; }
.aide { background: #fff; padding: 1rem 1.2rem; display: flex; flex-wrap: wrap; gap: .3rem 1.1rem; align-items: baseline; }
.aide dt { font-family: var(--font-h); font-weight: 700; font-size: 1.02rem; color: var(--c-navy); min-width: 150px; }
.aide dd { margin: 0; color: var(--c-ink-soft); font-size: .96rem; flex: 1; }
.aide-note { background: var(--c-bg-soft); border: 1px solid var(--c-line); padding: 1.3rem 1.4rem; }
.aide-note__title { font-family: var(--font-h); font-weight: 700; font-size: 1.1rem; color: var(--c-navy); margin-bottom: .5rem; display: block; }

/* 13. Contenu éditorial ------------------------------------- */
.prose { max-width: var(--wrap-narrow); }
.prose > * + * { margin-top: 1.1em; }
.prose h2 { margin-top: 2em; }
.prose h3 { margin-top: 1.6em; }
.prose ul, .prose ol { padding-left: 1.3rem; }
.prose li { margin-top: .4em; }
.prose li::marker { color: var(--c-blue); }
.prose a { font-weight: 600; }
.prose figure { margin: 1.6em 0; }
.prose figcaption { font-size: .875rem; color: var(--c-muted); margin-top: .4rem; }
.prose blockquote {
  border-left: 3px solid var(--c-blue); padding: .3rem 0 .3rem 1rem;
  color: var(--c-ink-soft); font-style: italic;
}
.article-date { font-size: .85rem; color: var(--c-muted); margin-top: .4rem; }
.key-points {
  background: var(--c-ok-bg); border: 1px solid var(--c-ok-line);
  padding: 1rem 1.25rem;
  margin-top: 2em;}
.key-points h2, .key-points h3 { margin-top: 0; }

/* 14. Tableaux --------------------------------------------- */
.table-wrap { overflow-x: auto; margin: 1.4em 0; border: 1px solid var(--c-line); }
table { border-collapse: collapse; width: 100%; font-size: .97rem; }
th, td { text-align: left; padding: .7rem .9rem; border-bottom: 1px solid var(--c-line); vertical-align: top; }
thead th { background: var(--c-bg-soft); font-family: var(--font); font-size: .9rem; }
tbody tr:last-child td { border-bottom: 0; }
caption { caption-side: bottom; font-size: .85rem; color: var(--c-muted); padding-top: .5rem; text-align: left; }

/* 15. FAQ ------------------------------------------------- */
.faq__list { margin-top: 1rem; border-top: 1px solid var(--c-line); max-width: var(--wrap-narrow); }
.faq__item { border-bottom: 1px solid var(--c-line); }
.faq__item summary {
  list-style: none; cursor: pointer; padding: 1.1rem 2rem 1.1rem 0; position: relative;
  font-weight: 700; font-family: var(--font-h); color: var(--c-navy); font-size: 1.05rem;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after {
  content: "+"; position: absolute; right: .2rem; top: 1rem; font-size: 1.4rem; color: var(--c-primary); font-weight: 600;
}
.faq__item[open] summary::after { content: "–"; }
.faq__answer { padding-bottom: 1.1rem; color: var(--c-ink-soft); }
.faq__answer > *:first-child { margin-top: 0; }

/* 16. Étapes ------------------------------------------------ */
.band { background: var(--c-bg-soft); border-top: 1px solid var(--c-line); border-bottom: 1px solid var(--c-line); }
.steps__list { list-style: none; padding: 0; margin-top: 1.8rem; display: grid; gap: 1.2rem; }
.steps__item { background: #fff; border: 1px solid var(--c-line); border-top: 4px solid var(--c-blue); padding: 1.6rem 1.4rem; }
.steps__num {
  display: block; font-family: var(--font-h); font-weight: 800; font-size: .82rem;
  letter-spacing: .08em; color: var(--c-primary); margin-bottom: .7rem;
}
.steps__item h3 { margin: 0 0 .5rem; font-size: 1.15rem; }
.steps__note, .steps__note strong { color: var(--c-muted); font-size: .95rem; margin-top: 1.4rem; }

.zone p { max-width: var(--wrap-narrow); color: var(--c-ink-soft); }

/* 17. Section locale (sombre) -------------------------------- */
.local { background: var(--c-navy); color: #c6d8e5; }
.local strong { color: #fff; }
.local a { color: #cfe0ec; }
.local a:hover { color: var(--c-primary); }
.local h2 { color: #fff; }
.local__cases { display: grid; gap: 1rem; align-content: start; margin-top: 1.4rem; }
.case { border-left: 3px solid var(--c-primary); padding: .3rem 0 .3rem 1.1rem; font-size: 1rem; }
.case__title { display: block; font-family: var(--font-h); font-weight: 700; font-size: 1.02rem; color: #fff; margin-bottom: .3rem; }
.local .zone { margin-top: 2rem; padding-top: 1.4rem; border-top: 1px solid #23486a; color: #9fb9cd; font-size: .92rem; }

/* 18. Encarts / notices --------------------------------------- */
.notice {
  padding: 1rem 1.25rem; font-size: .97rem; margin: 1.4em 0;
}
.notice--maj { background: var(--c-warn-bg); border: 1px solid var(--c-warn-line); color: #6B4A22; }
.notice--maj a { color: var(--c-blue-d); }
.notice--info { background: var(--c-ok-bg); border: 1px solid var(--c-ok-line); }
.notice--info ul { padding-left: 1.2rem; }

/* 19. Formulaire de devis ------------------------------ */
.devis-form { padding-block: clamp(2rem, 1.4rem + 3vw, 3.5rem); }
.devis-form__embed { border: 1px solid var(--c-line); overflow: hidden; }
.devis-form__legal { font-size: .85rem; color: var(--c-muted); margin-top: 1.4rem; max-width: var(--wrap-narrow); }

/* 20. CTA --------------------------------------------- */
.cta--band { background: var(--c-primary); color: #fff; padding-block: 3rem; margin-top: 3rem; }
.cta--band .cta__title { color: #fff; margin-top: 0; }
.cta--band .cta__text { color: #fff6f0; margin-top: .5rem; }
.cta--band .cta__disclaimer { color: #fff3ec; font-size: .82rem; margin-top: 1rem; }
.cta--band .btn--dark:hover { background: var(--c-navy-deep); }
.cta__inner { display: grid; gap: 1.2rem; }
.cta--inline { background: var(--c-warn-bg); border: 1px solid var(--c-warn-line); padding: 1.5rem; margin: 2em 0; }
.cta--inline .cta__title { margin-top: 0; font-size: 1.25rem; }
.cta--inline .cta__disclaimer { font-size: .8rem; color: var(--c-muted); margin-top: .8rem; }

/* 21. Liens connexes -------------------------------- */
.related { background: var(--c-bg-soft); padding-block: 1rem; margin-top: 3rem; }
.related h2 { margin-top: 0; }
.related__list { list-style: none; padding: 0; margin-top: 1rem; display: grid; gap: .6rem; }
.related__list li { display: flex; flex-wrap: wrap; gap: .5rem; align-items: baseline; }
.related__list a { font-weight: 600; text-decoration: none; }
.related__list span { color: var(--c-muted); font-size: .9rem; }

/* 22. Pied de page --------------------------------- */
.site-footer { background: var(--c-navy-deep); color: #9fb9cd; padding-block: 3rem 1.5rem; font-size: .95rem; }
.site-footer h2 { color: #fff; font-size: .82rem; font-family: var(--font-h); text-transform: uppercase; letter-spacing: .06em; margin: 0 0 .8rem; }
.site-footer a { color: #9fb9cd; text-decoration: none; }
.site-footer a:hover { color: #fff; }
.site-footer__grid { display: grid; gap: 2rem; }
.site-footer__brand strong { color: #fff; font-family: var(--font-h); font-size: 1.15rem; font-weight: 700; }
.site-footer__brand p { margin-top: .6rem; }
.site-footer__note { color: #7896ad; font-size: .85rem; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: .5rem; }
.site-footer__bottom { margin-top: 2.2rem; padding-top: 1.2rem; border-top: 1px solid #16324a; color: #6d8ba3; font-size: .85rem; display: grid; gap: .3rem; }

/* 23. Responsive ---------------------------------- */
@media (max-width: 899px) {
	.site-nav.is-open {
		position: fixed;
		display: block;
		top: 68px; left: 0; right: 0;
		width: 100%;
		text-align: center;
		padding-bottom: .75rem;
		border-top: 1px solid var(--c-line);
		max-height: calc(100vh - 68px); overflow-y: auto;
		background-color: #fff;}
	.site-nav.is-open .site-nav__list {
		text-align: left;}
	.site-nav.is-open .site-nav__list a {
		padding-inline: 2rem;}
}
@media (min-width: 560px) {
  .stats__inner { grid-template-columns: repeat(4, 1fr); }
}
@media (min-width: 700px) {
  .grid--2 { grid-template-columns: 1fr 1fr; }
  .grid--3 { grid-template-columns: repeat(3, 1fr); }
  .grid--4 { grid-template-columns: repeat(4, 1fr); }
  .cta__inner { grid-template-columns: 1fr auto; align-items: center; }
  .related__list { grid-template-columns: 1fr 1fr; }
  .grid-cards { grid-template-columns: repeat(2, 1fr); }
  .grid-avis { grid-template-columns: repeat(3, 1fr); }
}
@media (min-width: 860px) {
  .hero__grid { grid-template-columns: 1.1fr .9fr; gap: 3rem; }
  .hero__figure img { aspect-ratio: 4 / 5; object-position: 60% 48%; }
  .two-col { grid-template-columns: 1fr 1fr; gap: 3.5rem; }
  .steps__list { grid-template-columns: repeat(3, 1fr); }
}
@media (min-width: 900px) {
  .site-header__inner { min-height: 76px; }
  .nav-toggle { display: none; }
  .site-nav { display: flex !important; flex-basis: auto; width: auto; align-items: center; gap: 1.5rem; margin-left: auto; padding-top: 0; margin-top: 0; border-top: 0; max-height: none; overflow: visible; }
  .site-nav__list { display: flex; gap: 1.25rem; align-items: center; }
  .site-nav__list a { padding: .3rem 0; border: 0; font-weight: 600; font-size: .97rem; }
  .site-nav__list a:hover { border-bottom: 2px solid; }
  .site-nav__list a[aria-current="page"] { border-bottom: 2px solid var(--c-primary); }
  .site-nav__cta { margin: 0; }
  .site-footer__grid { grid-template-columns: 1.5fr 1fr 1fr 1fr; }
  .grid-cards { grid-template-columns: repeat(3, 1fr); }
}
@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition: none !important; }
}