/* CharpenteFermette.com — feuille de style
   Concept : le bureau d'études de charpente industrielle. Titres en slab façon plans d'atelier,
   vert sapin du bois de charpente, nœuds et cotes en caractères machine. */
@font-face{font-family:"Zilla Slab";src:url(fonts/zilla-slab-latin-700-normal.woff2) format("woff2");font-weight:700;font-display:swap}
@font-face{font-family:"Zilla Slab";src:url(fonts/zilla-slab-latin-500-normal.woff2) format("woff2");font-weight:500;font-display:swap}
@font-face{font-family:"Source Sans 3";src:url(fonts/source-sans-3-latin-400-normal.woff2) format("woff2");font-weight:400;font-display:swap}
@font-face{font-family:"Source Sans 3";src:url(fonts/source-sans-3-latin-600-normal.woff2) format("woff2");font-weight:600;font-display:swap}
@font-face{font-family:"Source Sans 3";src:url(fonts/source-sans-3-latin-400-italic.woff2) format("woff2");font-weight:400;font-style:italic;font-display:swap}
@font-face{font-family:"Fira Mono";src:url(fonts/fira-mono-latin-400-normal.woff2) format("woff2");font-weight:400;font-display:swap}
@font-face{font-family:"Fira Mono";src:url(fonts/fira-mono-latin-500-normal.woff2) format("woff2");font-weight:500;font-display:swap}

:root{
  --zinc:#F3F5F0;        /* fond : papier calque */
  --sheet:#FFFFFF;
  --ink:#1B2420;
  --muted:#56635C;
  --rule:#D2DAD4;
  --timber:#2E6A4A;      /* vert sapin (accent) */
  --timber-soft:#E2EFE6;
  --steel:#3B5B73;
  --steel-soft:#E4ECF1;
  --wood:#F1E6D4;
  --display:"Zilla Slab",Rockwell,"Roboto Slab",Georgia,serif;
  --body:"Source Sans 3","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --mono:"Fira Mono",ui-monospace,Consolas,monospace;
  --measure:68ch;
  color-scheme:light;
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
  --zinc:#111613;--sheet:#18201B;--ink:#E6ECE8;--muted:#9BAAA1;--rule:#2B3730;
  --timber:#7FC29B;--timber-soft:#1B2B21;--steel:#9DBBD1;--steel-soft:#1A2630;--wood:#2A241B;color-scheme:dark}}
:root[data-theme="dark"]{
  --zinc:#111613;--sheet:#18201B;--ink:#E6ECE8;--muted:#9BAAA1;--rule:#2B3730;
  --timber:#7FC29B;--timber-soft:#1B2B21;--steel:#9DBBD1;--steel-soft:#1A2630;--wood:#2A241B;color-scheme:dark}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--zinc);color:var(--ink);font:400 1.125rem/1.65 var(--body)}
img,svg{max-width:100%;height:auto}
a{color:var(--steel);text-underline-offset:.18em;text-decoration-thickness:1px}
a:hover{color:var(--timber)}
:focus-visible{outline:3px solid var(--timber);outline-offset:2px}
.wrap{max-width:1120px;margin-inline:auto;padding-inline:clamp(16px,4vw,32px)}
.skip{position:absolute;left:-9999px}.skip:focus{left:16px;top:16px;background:var(--sheet);padding:8px 12px;z-index:9}

/* En-tête */
.site-head{background:var(--sheet);border-bottom:1px solid var(--rule)}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px 24px;flex-wrap:wrap;padding-block:14px}
.brand img{display:block;height:48px;width:auto}
.nav{display:flex;flex-wrap:wrap;gap:4px 20px;font:500 .8rem/1.4 var(--mono);letter-spacing:.04em;text-transform:uppercase}
.nav a{color:var(--ink);text-decoration:none;padding-block:4px;border-bottom:2px solid transparent}
.nav a:hover,.nav a[aria-current]{border-bottom-color:var(--timber);color:var(--ink)}
.brand .logo-dark{display:none}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .brand .logo-light{display:none}:root:not([data-theme="light"]) .brand .logo-dark{display:block}}
:root[data-theme="dark"] .brand .logo-light{display:none}:root[data-theme="dark"] .brand .logo-dark{display:block}

.disclosure-bar{background:var(--timber-soft);color:var(--ink);font:400 .78rem/1.5 var(--mono)}
.disclosure-bar .wrap{padding-block:7px}

/* Typo */
h1,h2,h3{font-family:var(--display);line-height:1.02;text-wrap:balance;margin:0}
h1{font-weight:700;font-size:clamp(2.4rem,5.6vw,4rem);letter-spacing:-.01em;line-height:1.04}
h2{font-weight:700;font-size:clamp(1.7rem,3.2vw,2.2rem);margin-top:2.4em;margin-bottom:.5em}
h3{font-weight:700;font-size:1.35rem;margin-top:1.8em;margin-bottom:.35em}
p,ul,ol{margin:0 0 1.05em}
li{margin-bottom:.35em}
strong{font-weight:600}
.eyebrow{font:500 .78rem/1.3 var(--mono);letter-spacing:.1em;text-transform:uppercase;color:var(--timber);margin:0 0 .8em}
.lede{font-size:1.2rem;line-height:1.6;color:var(--ink);max-width:var(--measure)}
.meta{font:400 .8rem/1.5 var(--mono);color:var(--muted)}
.meta a{color:var(--muted)}
code,.ref{font-family:var(--mono);font-size:.88em;background:var(--steel-soft);padding:.05em .35em;border-radius:3px}

/* Héros */
.hero{background:var(--sheet);border-bottom:1px solid var(--rule)}
.hero .wrap{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(0,1fr);gap:clamp(24px,5vw,64px);align-items:center;padding-block:clamp(36px,6vw,72px)}
.hero h1 span{color:var(--timber)}
.hero .lede{margin-top:1em}
.hero figure{margin:0}
.hero figcaption,.fig figcaption{font:400 .75rem/1.5 var(--mono);color:var(--muted);margin-top:8px}
.btn-row{display:flex;flex-wrap:wrap;gap:10px;margin-top:1.4em}
.btn{display:inline-block;font:500 .85rem/1 var(--mono);letter-spacing:.03em;text-decoration:none;padding:13px 18px;border:2px solid var(--ink);color:var(--ink);background:transparent}
.btn:hover{background:var(--ink);color:var(--sheet)}
.btn.primary{background:var(--timber);border-color:var(--timber);color:var(--sheet)}
.btn.primary:hover{background:var(--ink);border-color:var(--ink);color:var(--sheet)}

/* Schémas (SVG en ligne) */
.dg-steel{fill:var(--steel)} .dg-wood{fill:var(--timber-soft);stroke:var(--timber);stroke-width:1.5}
.dg-ring{fill:none;stroke:var(--timber);stroke-width:1.2;opacity:.7}
.dg-support{fill:var(--zinc);stroke:var(--rule);stroke-width:1}
.dg-hole{fill:var(--sheet)} .dg-nail{fill:var(--timber)}
.dg-dim{stroke:var(--ink);stroke-width:1;fill:none} .dg-arrow{fill:var(--ink)}
.dg-txt{font:500 11px var(--mono);fill:var(--ink)} .dg-txt.m{fill:var(--muted)} .dg-txt.a{fill:var(--timber)}

/* Mise en page article */
.article{padding-block:clamp(32px,5vw,56px)}
.article .wrap{display:grid;grid-template-columns:230px minmax(0,1fr);gap:clamp(24px,4vw,56px);align-items:start}
.article-head{grid-column:1/-1;max-width:880px}
.article-head .meta{margin-top:1.1em}
.side{position:sticky;top:20px;font:400 .82rem/1.55 var(--mono);border-top:3px solid var(--ink);padding-top:12px}
.side h2{font:500 .72rem/1.3 var(--mono);letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin:0 0 8px}
.side ol{list-style:none;padding:0;margin:0 0 20px;counter-reset:t}
.side li{margin:0;border-bottom:1px solid var(--rule)}
.side li a{display:block;padding:7px 0;color:var(--ink);text-decoration:none}
.side li a:hover{color:var(--timber)}
.side dl{display:grid;grid-template-columns:auto 1fr;gap:4px 10px;margin:0}
.side dt{color:var(--muted)} .side dd{margin:0}
.body{min-width:0;max-width:var(--measure)}
.body > h2:first-child{margin-top:0}
.body ul,.body ol{padding-left:1.25em}

/* Réponse courte (extrait optimisé) */
.answer{background:var(--sheet);border:1px solid var(--rule);border-left:6px solid var(--timber);padding:18px 22px;margin:0 0 1.6em}
.answer .eyebrow{margin-bottom:.4em}
.answer p:last-child{margin-bottom:0}

.note{background:var(--steel-soft);padding:14px 18px;margin:1.4em 0;font-size:.97rem}
.note strong:first-child{font-family:var(--mono);font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;display:block;color:var(--steel);margin-bottom:4px}
.note p:last-child{margin-bottom:0}

.fig{margin:1.6em 0;background:var(--sheet);border:1px solid var(--rule);padding:16px}
.fig svg{display:block;margin-inline:auto}

/* Tableaux techniques */
.table-scroll{overflow-x:auto;margin:1.4em 0;border:1px solid var(--rule);background:var(--sheet)}
table{border-collapse:collapse;width:100%;font:400 .86rem/1.45 var(--mono);font-variant-numeric:tabular-nums}
th,td{text-align:left;padding:9px 12px;border-bottom:1px solid var(--rule);vertical-align:top}
th{font-weight:500;background:var(--steel-soft);color:var(--ink);white-space:nowrap}
tr:last-child td{border-bottom:0}

/* Étapes */
.steps{list-style:none;padding:0!important;counter-reset:s}
.steps > li{counter-increment:s;position:relative;padding:0 0 1.1em 3.1em;margin:0}
.steps > li::before{content:counter(s,decimal-leading-zero);position:absolute;left:0;top:.1em;font:700 1.5rem/1 var(--display);color:var(--timber)}
.steps > li strong:first-child{display:block;font-family:var(--display);font-size:1.25rem;font-weight:700;letter-spacing:.01em}

/* FAQ */
.faq details{border-bottom:1px solid var(--rule);padding:12px 0}
.faq summary{cursor:pointer;font-weight:600;list-style-position:outside}
.faq details p{margin:.6em 0 0}

/* Grille de guides (accueil) */
.guides{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px;margin:1.4em 0 0}
.guide{display:flex;flex-direction:column;gap:8px;background:var(--sheet);border:1px solid var(--rule);padding:20px;text-decoration:none;color:var(--ink)}
.guide:hover{border-color:var(--ink);color:var(--ink)}
.guide .k{font:500 .72rem/1.3 var(--mono);letter-spacing:.08em;text-transform:uppercase;color:var(--timber)}
.guide h3{margin:0;font-size:1.55rem}
.guide p{margin:0;font-size:.95rem;color:var(--muted)}

/* Produits (comparatif) */
.pick{background:var(--sheet);border:1px solid var(--rule);margin:1.4em 0;display:grid;grid-template-columns:minmax(0,1fr) auto;gap:4px 20px;padding:20px 22px}
.pick h3{margin:0;grid-column:1/-1}
.pick .tag{font:500 .72rem/1.3 var(--mono);letter-spacing:.08em;text-transform:uppercase;color:var(--timber);grid-column:1/-1;margin-bottom:4px}
.pick p,.pick ul{grid-column:1/-1;margin-bottom:.6em}
.pick .specs{font:400 .82rem/1.5 var(--mono);color:var(--muted)}
.pick .btn{justify-self:start;grid-column:1/-1;margin-top:6px}

/* Calculateur */
.calc{background:var(--sheet);border:2px solid var(--ink);padding:20px 22px;margin:1.6em 0}
.calc form{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:14px;align-items:end}
.calc label{display:flex;flex-direction:column;gap:6px;font:500 .75rem/1.3 var(--mono);letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.calc input,.calc select{font:500 1.05rem/1.2 var(--mono);padding:10px;border:1px solid var(--rule);background:var(--zinc);color:var(--ink);width:100%}
.calc output{display:block;margin-top:16px;font:400 .95rem/1.6 var(--mono);border-top:1px solid var(--rule);padding-top:14px}
.calc output b{font-weight:500;color:var(--timber)}

/* Pied de page */
.site-foot{background:#1B2420;color:#C9D3D1;margin-top:56px;font:400 .82rem/1.6 var(--mono)}
.site-foot .wrap{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:24px;padding-block:40px}
.site-foot h2{font:500 .72rem/1.3 var(--mono);letter-spacing:.1em;text-transform:uppercase;color:#7FC29B;margin:0 0 10px}
.site-foot a{color:#E6ECEA;text-decoration:none}
.site-foot a:hover{text-decoration:underline;color:#fff}
.site-foot ul{list-style:none;padding:0;margin:0}
.site-foot .fine{grid-column:1/-1;border-top:1px solid #2B3730;padding-top:18px;color:#9AA7A4}

.page{padding-block:clamp(32px,5vw,56px)}
.page .body{max-width:var(--measure)}
.page h1{margin-bottom:.4em}

@media (max-width:860px){
  .hero .wrap,.article .wrap{grid-template-columns:minmax(0,1fr)}
  .side{position:static}
}
@media (prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
html{scroll-behavior:smooth}
.dg-block{fill:var(--rule);stroke:var(--muted);stroke-width:1}

/* Spécificités fermette */
.answer{border:0;background:var(--timber-soft);border-radius:0}
.hero{border-bottom:0;box-shadow:inset 0 -6px 0 var(--timber)}
.side{border-top-color:var(--timber)}
.dg-truss{stroke:var(--timber);stroke-width:5;stroke-linecap:round;fill:none}
.dg-truss.thin{stroke-width:3}
.dg-node{fill:var(--ink)}
.dg-room{fill:var(--timber-soft)}
.dg-block{fill:var(--rule);stroke:var(--muted);stroke-width:1}
.trusses{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin:1.4em 0}
.trusses figure{margin:0;background:var(--sheet);border:1px solid var(--rule);padding:12px}
.trusses figcaption{font:500 .78rem/1.4 var(--mono);color:var(--ink);margin-top:6px}
.trusses figcaption span{display:block;color:var(--muted);font-weight:400}
.dg-halo{paint-order:stroke;stroke:var(--sheet);stroke-width:4px;stroke-linejoin:round}

/* Maquettes 3D et illustrations */
.v3d{margin:1.6em 0;background:var(--sheet);border:1px solid var(--rule);padding:0}
.v3d-stage{position:relative;aspect-ratio:16/9;overflow:hidden;background:#F3F5F0;touch-action:pan-y}
.v3d-stage.live{touch-action:none;cursor:grab}
.v3d-stage > img{display:block;width:100%;height:100%;object-fit:cover}
.v3d-stage.live > img{display:none}
.v3d-canvas{position:absolute;inset:0;width:100%!important;height:100%!important;display:block}
.v3d-labels{position:absolute;inset:0;pointer-events:none}
.v3d-labels span{position:absolute;left:0;top:0;white-space:nowrap;font:500 11px/1.2 var(--mono);color:#1B2420;background:rgba(255,255,255,.88);border:1px solid #C9D3CC;padding:3px 6px;transition:opacity .2s}
.v3d-labels span.big{font:700 15px/1.2 var(--display);background:#1B2420;color:#fff;border-color:#1B2420;padding:5px 9px}
.v3d-btn{position:absolute;left:14px;bottom:14px;font:500 .8rem/1 var(--mono);letter-spacing:.03em;padding:12px 16px;border:0;background:var(--timber);color:#fff;cursor:pointer;box-shadow:0 2px 10px rgba(0,0,0,.18)}
.v3d-btn:hover{background:#1B2420}
.v3d-btn:disabled{background:#56635C;cursor:default}
.v3d figcaption,.photo figcaption{font:400 .75rem/1.5 var(--mono);color:var(--muted);padding:10px 14px;border-top:1px solid var(--rule)}
.v3d-hint{font:400 .72rem/1.4 var(--mono);color:var(--muted);padding:8px 14px 0}
.photo{margin:1.6em 0;background:var(--sheet);border:1px solid var(--rule)}
.photo img{display:block;width:100%;height:auto}
.hero .v3d{margin:0}
@media (max-width:600px){.v3d-labels span{font-size:9.5px;padding:2px 4px}.v3d-labels span.big{font-size:12px}.v3d-btn{left:10px;bottom:10px;padding:10px 12px}}
/* Guides en accueil */
.home-guides{background:var(--zinc);padding-block:clamp(28px,4vw,48px) 0}
.home-guides h2{margin-top:0;margin-bottom:.2em}
.home-guides h2#bois,.home-guides h2#entretien{margin-top:1.4em}
.home-guides .guides{margin-bottom:.4em}

.author-card{display:flex;gap:16px;align-items:center;background:var(--sheet);border:1px solid var(--rule);padding:16px;margin:1.2em 0}
.author-card img{border-radius:50%;flex:none}
.author-name{font:700 1.3rem/1.2 var(--display);margin:0 0 4px}
.author-card .meta{margin:0}
.sources{font-size:.95rem;color:var(--muted)}

/* ---------- Mobile : menu, en-tête, sommaire ---------- */
.nav-toggle{display:none}
.disc-short{display:none}
@media (max-width:860px){
  .site-head{position:sticky;top:0;z-index:30;box-shadow:0 1px 0 var(--rule)}
  .site-head .wrap{flex-wrap:nowrap;padding-block:10px}
  .brand img{height:38px}
  .nav-toggle{display:inline-flex;align-items:center;gap:10px;min-height:44px;padding:8px 14px;border:2px solid var(--ink);background:var(--sheet);color:var(--ink);font:500 .8rem/1 var(--mono);letter-spacing:.06em;text-transform:uppercase;cursor:pointer}
  .nav-toggle-bars,.nav-toggle-bars::before,.nav-toggle-bars::after{display:block;width:18px;height:2px;background:currentColor;position:relative;transition:transform .2s}
  .nav-toggle-bars::before,.nav-toggle-bars::after{content:"";position:absolute;left:0}
  .nav-toggle-bars::before{top:-6px}.nav-toggle-bars::after{top:6px}
  .nav-toggle[aria-expanded="true"] .nav-toggle-bars{background:transparent}
  .nav-toggle[aria-expanded="true"] .nav-toggle-bars::before{transform:translateY(6px) rotate(45deg)}
  .nav-toggle[aria-expanded="true"] .nav-toggle-bars::after{transform:translateY(-6px) rotate(-45deg)}
  html.js .nav{display:none}
  html.js .nav.open{display:flex;position:absolute;left:0;right:0;top:100%;flex-direction:column;gap:0;background:var(--sheet);border-top:1px solid var(--rule);border-bottom:3px solid var(--timber);box-shadow:0 12px 24px rgba(0,0,0,.12);max-height:calc(100vh - 64px);overflow-y:auto;padding:4px 0}
  html.js .nav.open a{padding:14px clamp(16px,4vw,32px);border-bottom:1px solid var(--rule);font-size:.9rem}
  html.js .nav.open a:last-child{border-bottom:0}
  html.js .nav.open a[aria-current]{border-left:4px solid var(--timber);background:var(--timber-soft)}
  .site-head{position:sticky}
  .site-head .wrap{position:relative}
  .disc-long{display:none}.disc-short{display:inline}
  .disclosure-bar{font-size:.72rem}
  h1{font-size:clamp(2rem,8.5vw,2.6rem)}
  .lede{font-size:1.08rem}
  .article{padding-block:24px}
  .article .wrap{gap:16px}
  .btn-row .btn{flex:1 1 auto;text-align:center}
  /* sommaire repliable */
  html.js .side{border-top:0;padding-top:0}
  html.js .side > :not(.side-toggle){display:none}
  html.js .side.open > :not(.side-toggle){display:block}
  html.js .side.open dl{display:grid}
  .side-toggle{display:flex;width:100%;justify-content:space-between;align-items:center;min-height:48px;padding:12px 14px;background:var(--sheet);border:1px solid var(--rule);border-top:3px solid var(--timber);font:500 .8rem/1.2 var(--mono);letter-spacing:.06em;text-transform:uppercase;color:var(--ink);cursor:pointer}
  .side-toggle::after{content:"▾";font-size:1rem}
  .side.open .side-toggle::after{content:"▴"}
  html.js .side.open{background:var(--sheet);border:1px solid var(--rule);border-top:0;padding:0 14px 12px}
  html.js .side.open .side-toggle{margin:0 -14px 12px;width:calc(100% + 28px);border-left:0;border-right:0}
  .table-scroll{margin-inline:calc(-1 * clamp(16px,4vw,32px));border-left:0;border-right:0}
  table{font-size:.8rem}
  th,td{padding:8px 10px}
  .pick{padding:16px}
  .pick .btn{width:100%;text-align:center}
  .site-foot .wrap{grid-template-columns:1fr 1fr;gap:20px}
  .site-foot .wrap > div:first-child,.site-foot .fine{grid-column:1/-1}
  .site-foot li{margin-bottom:.5em}
}
@media (min-width:861px){ .side-toggle{display:none} }
@media (max-width:420px){ .site-foot .wrap{grid-template-columns:1fr} .nav-toggle-label{display:none} .nav-toggle{padding:10px 12px} }

/* ---------- Accueil : images ---------- */
.hero-fig img{display:block;width:100%;height:auto;border:1px solid var(--rule);background:#F3F5F0}
.guide{padding:0;overflow:hidden}
.guide-img{display:block;width:100%;height:auto;aspect-ratio:16/9;object-fit:cover;background:#F3F5F0;border-bottom:1px solid var(--rule);transition:transform .25s}
.guide:hover .guide-img{transform:scale(1.03)}
.guide .k{padding:16px 20px 0}
.guide h3{padding:0 20px}
.guide p{padding:0 20px 18px}
.guides{grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}
@media (max-width:860px){
  .hero .wrap{gap:20px;padding-block:24px 28px}
  .hero-fig{order:-1;margin:0 calc(-1 * clamp(16px,4vw,32px))}
  .hero-fig img{border-left:0;border-right:0}
  .hero-fig figcaption{padding:0 clamp(16px,4vw,32px)}
  .guides{grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:12px}
  .guide .k{padding:10px 12px 0;font-size:.62rem}
  .guide h3{padding:0 12px;font-size:1.1rem}
  .guide p{display:none}
  .guide{padding-bottom:12px}
}
@media (prefers-reduced-motion:reduce){.guide-img{transition:none}.guide:hover .guide-img{transform:none}}
@media (max-width:860px){[id]{scroll-margin-top:76px}}