/* Studio Si, feuille de style unique. Tokens de couleur en tête, thème sombre inclus. */
:root {
  --paper: #FFFFFF; --ink: #000000; --ink-2: #5C5C5C; --rule: #E3E3E3; --tint: #F3F3F2; --red: #DA291C; --on-ink: #FFFFFF;
  --font: "Hanken Grotesk", "Helvetica Neue", Helvetica, Arial, system-ui, sans-serif;
  --gutter: clamp(1.25rem, 5vw, 3.5rem); --measure: 38rem;
  color-scheme: light dark; box-sizing: border-box;
  padding-top: env(safe-area-inset-top, 0px); padding-bottom: env(safe-area-inset-bottom, 0px);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --paper: #181818; --ink: #F4F4F3; --ink-2: #A8A8A6; --rule: #333332; --tint: #222221; --red: #FF4A3D; --on-ink: #181818; }
}
:root[data-theme="dark"] { --paper: #181818; --ink: #F4F4F3; --ink-2: #A8A8A6; --rule: #333332; --tint: #222221; --red: #FF4A3D; --on-ink: #181818; }
html { scroll-padding-top: calc(env(safe-area-inset-top, 0px) + 5.5rem); scroll-behavior: smooth; }
*, *::before, *::after { box-sizing: inherit; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--font); font-size: 1.125rem; line-height: 1.6; overflow-x: clip; -webkit-font-smoothing: antialiased; }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--red); outline-offset: 3px; }
.wrap { max-width: 76rem; margin: 0 auto; padding-inline: var(--gutter); }
.skip { position: absolute; left: -999px; }
.skip:focus { left: var(--gutter); top: 1rem; background: var(--paper); padding: .5rem 1rem; z-index: 10; }
h1, h2, h3 { margin: 0; line-height: 1.05; letter-spacing: -0.03em; font-weight: 700; }
h2 { font-size: clamp(2.1rem, 4.6vw, 3.6rem); }
h3 { font-size: 1.3rem; letter-spacing: -0.015em; line-height: 1.2; }
p { margin: 0; }
/* « si » mis en avant partout où il apparaît ; --si ajuste le rouge sur fond inversé (contact) pour garder le contraste AA */
.si-mark { color: var(--si, var(--red)); }
.si-mark.flash, .sancte.flash, .sancte.flash .si-mark { background: var(--red); color: #fff; box-shadow: 0 0 0 .08em var(--red); }
::selection { background: var(--red); color: #fff; }
.contact { --si: #FF4A3D; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .contact { --si: #C8231A; } }
:root[data-theme="dark"] .contact { --si: #C8231A; }
.intro { color: var(--ink-2); max-width: var(--measure); margin-top: 1.1rem; font-size: 1.2rem; }

/* header */
/* en-tête collant ; le si du logo n’apparaît qu’une fois que le si du hero l’a rejoint (voir site.js) */
.bar { position: sticky; top: 0; z-index: 20; background: var(--paper); border-bottom: 1px solid transparent; transition: border-color .2s; }
.bar.is-stuck { border-bottom-color: var(--rule); }
.top { display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; padding-block: 1.1rem; }
.js .bar .logo .si { opacity: 0; }
.js .bar .logo.is-home .si { opacity: 1; }
.flyer { position: fixed; left: 0; top: 0; width: 1px; height: 1px; background: var(--red); transform-origin: 0 0; pointer-events: none; z-index: 30; visibility: hidden; }
.home { display: inline-flex; color: var(--ink); }
.logo { height: 2.1rem; width: auto; display: block; }
.logo .si { fill: var(--red); }
.nav { display: flex; align-items: center; gap: 2rem; }
.nav ul { list-style: none; margin: 0; padding: 0; display: flex; gap: 1.75rem; }
.nav a { text-decoration: none; font-weight: 500; color: var(--ink-2); }
.nav a:hover { color: var(--ink); }
.nav .btn, .nav .btn:hover { color: var(--on-ink); }
.nav .btn:hover { color: #fff; }
.btn { display: inline-block; font-weight: 600; font-size: 1rem; text-decoration: none; color: var(--on-ink); background: var(--ink); padding: .8rem 1.3rem; border-radius: 3px; white-space: nowrap; }
.btn:hover { background: var(--red); color: #fff; }
.btn-lg { font-size: 1.08rem; padding: 1rem 1.6rem; }

/* hero */
.hero { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: 0 3rem; align-items: end; padding-top: clamp(3rem, 9vw, 7rem); padding-bottom: clamp(3.5rem, 8vw, 6rem); }
h1 { grid-column: 1 / -1; font-size: clamp(2.2rem, 7.6vw, 6.6rem); letter-spacing: -0.045em; line-height: .98; font-weight: 800; }
/* accroche : « Si » fixe à gauche, la suite en rotation, empilée dans une même cellule (la hauteur suit la plus longue) */
.tagline { display: grid; grid-template-columns: auto minmax(0, 1fr); column-gap: .24em; }
.rotator { display: grid; }
.rotator > span { grid-area: 1 / 1; opacity: 0; visibility: hidden; transform: translateY(.3em); transition: opacity .45s ease, transform .6s cubic-bezier(.2,.8,.2,1), visibility 0s .6s; }
.rotator > .is-on { opacity: 1; visibility: visible; transform: none; transition-delay: .15s, .15s, 0s; }
.rotator > .is-out { transform: translateY(-.3em); }
@media (prefers-reduced-motion: reduce) { .rotator > span { transition: none; } }
.lead { font-size: clamp(1.15rem, 1.9vw, 1.35rem); color: var(--ink-2); max-width: 34rem; margin: 1.75rem 0 2.25rem; }
.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.75rem; }
.link { font-weight: 600; text-decoration: underline; text-decoration-color: var(--red); text-decoration-thickness: 2px; text-underline-offset: .25em; }
.eyebrow { grid-column: 1 / -1; font-size: 1rem; font-weight: 600; color: var(--ink-2); margin-bottom: 1.4rem; letter-spacing: .01em; }
.offer { list-style: none; margin: -.75rem 0 2.25rem; padding: 0; display: flex; flex-wrap: wrap; gap: .6rem 1.5rem; }
.offer a { display: inline-flex; align-items: center; gap: .55rem; font-weight: 600; text-decoration: none; }
.offer a::before { content: ""; width: .5rem; height: .5rem; background: var(--red); }
.offer a:hover { text-decoration: underline; text-decoration-color: var(--red); text-underline-offset: .25em; }
.hero-art { position: relative; padding-bottom: .5rem; margin-top: 3rem; }
.hero-art .hero-mark { width: 92%; }
/* feuille de route : une étape de projet sous chaque note, comme les paroles d’un chant */
.hero-mark .step { font-family: var(--font); font-size: 10px; font-weight: 600; fill: var(--ink-2); text-anchor: end; letter-spacing: 0; }
.hero-mark .step.last { fill: var(--red); font-weight: 800; }
.hero-mark { display: block; width: 100%; height: auto; overflow: visible; color: var(--ink); }
.hero-mark .staffline, .hero-mark .clef, .hero-mark .deg { fill: var(--ink); }
.hero-mark .note { fill: var(--red); transform-box: fill-box; transform-origin: top; animation: hang .7s cubic-bezier(.2,.8,.2,1) .35s both; }
@keyframes hang { from { transform: scaleY(0); } to { transform: scaleY(1); } }
@media (prefers-reduced-motion: reduce) { .hero-mark .note { animation: none; } html { scroll-behavior: auto; } }

/* portée de navigation : dans l’en-tête collant, dès la section Services ; le si rouge (.cursor) monte d’un degré par section, le nom de la section s’affiche à côté */
.staffnav { display: none; align-items: center; gap: .8rem; color: var(--ink); }
.bar.has-staff .staffnav { display: flex; animation: appear .35s ease both; }
.bar.has-staff .nav > nav:not(.staffnav) { display: none; }
@keyframes appear { from { opacity: 0; } }
.staffnav svg { display: block; height: 2.5rem; width: auto; overflow: visible; }
.staffnav-label { font-weight: 700; font-size: 1.05rem; letter-spacing: -0.01em; white-space: nowrap; min-width: 6.5rem; }
.staffnav .staffline, .staffnav .clef { fill: currentColor; }
.staffnav .key { fill: currentColor; opacity: .2; transition: opacity .3s; }
.staffnav .key.past { opacity: 1; }
.staffnav a:hover .key, .staffnav a:focus-visible .key { opacity: 1; fill: var(--red); }
.staffnav a:focus-visible { outline: none; }
.staffnav a:focus-visible .hit { stroke: var(--red); stroke-width: 4; }
.staffnav .cursor { fill: var(--red); pointer-events: none; transform: translate(calc(var(--d, 0) * 36px), calc(var(--d, 0) * -13px)); transition: transform .55s cubic-bezier(.2,.8,.2,1); }
@media (prefers-reduced-motion: reduce) { .bar.has-staff .staffnav { animation: none; } .staffnav .cursor { transition: none; } }
.hero-mark rect.ring, .staffnav rect.ring { fill: var(--red); opacity: 1; }
@media (prefers-reduced-motion: reduce) { .staffnav, .staffnav .cursor { transition: none; } }

/* bandeau clients */
.clients { border-top: 1px solid var(--rule); padding-block: 1.6rem; }
.clients .wrap { display: flex; flex-wrap: wrap; align-items: baseline; gap: .6rem 2rem; }
.clients-label { font-size: .95rem; color: var(--ink-2); }
.clients-list { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; align-items: center; gap: .5rem 1.1rem; font-weight: 700; letter-spacing: -0.01em; }
.clients-list li + li::before { content: ""; display: inline-block; width: .35rem; height: .35rem; background: var(--red); margin-right: 1.1rem; vertical-align: .2em; }

/* sections */
section { padding-block: clamp(4.5rem, 10vw, 8rem); border-top: 1px solid var(--rule); }

.services { margin-top: clamp(2.5rem, 5vw, 4rem); display: grid; gap: 0; }
.service { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 1.25rem 3.5rem; padding-block: 2.5rem; border-top: 1px solid var(--rule); }
.service:first-child { border-top: 0; padding-top: 0; }
.service-head h3 { font-size: clamp(1.5rem, 2.6vw, 2.05rem); }
.service-head p { color: var(--ink-2); margin-top: .8rem; max-width: 30rem; }
.ticks { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .9rem 2rem; }
.ticks li { position: relative; padding-left: 1.35rem; line-height: 1.45; }
.ticks li::before { content: ""; position: absolute; left: 0; top: .5em; width: .5rem; height: .5rem; background: var(--red); }
.ideal { margin-top: 1.5rem; color: var(--ink-2); font-size: 1rem; }
.ideal span { color: var(--ink); font-weight: 600; }

.cases { margin-top: clamp(2.5rem, 5vw, 4rem); display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 2.5rem 2rem; }
.shot { margin: 0 0 1.25rem; aspect-ratio: 16 / 10; border-radius: 6px; overflow: hidden; background: var(--tint); border: 1px solid var(--rule); }
.shot img { width: 100%; height: 100%; object-fit: cover; object-position: top left; display: block; }
.cover { position: relative; height: 100%; padding: 1.25rem 1.4rem; display: flex; flex-direction: column; justify-content: space-between; }
.meta { display: flex; flex-wrap: wrap; align-items: center; gap: .4rem .5rem; margin-bottom: .1rem; }
.kind { font-size: .9rem; font-weight: 600; color: var(--ink-2); margin-right: .3rem; }
.tag { font-size: .72rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--ink); border: 1px solid var(--rule); padding: .1rem .4rem; }
.cover-name { font-size: clamp(1.5rem, 2.4vw, 2rem); font-weight: 700; letter-spacing: -0.03em; line-height: 1.05; max-width: 80%; }
.cover-line { position: absolute; left: 0; right: 0; top: 42%; height: 2px; background: var(--ink); opacity: .9; }
.cover-note { position: absolute; right: 12%; top: calc(42% + 2px); width: 11%; aspect-ratio: 1; background: var(--red); }
.case h3 { margin: .3rem 0 .5rem; }
.case p { color: var(--ink-2); font-size: 1.02rem; max-width: 26rem; }

.why { margin-top: clamp(2.5rem, 5vw, 4rem); display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 2.75rem 4rem; }
.why-item h3 { font-size: 1.45rem; display: flex; align-items: baseline; gap: .75rem; }
.why-item h3::before { content: ""; flex: none; width: .5em; height: .5em; background: var(--red); }
.why-item p { color: var(--ink-2); margin-top: .6rem; max-width: 30rem; }

.steps { list-style: none; padding: 0; margin: clamp(2.5rem, 5vw, 4rem) 0 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 2.5rem 2rem; counter-reset: step; }
.steps li { counter-increment: step; border-top: 2px solid var(--ink); padding-top: 1.25rem; }
.steps li::before { content: counter(step, upper-roman); display: block; font-weight: 700; font-size: 1.1rem; color: var(--red); margin-bottom: .9rem; letter-spacing: .02em; }
.steps h3 { font-size: 1.4rem; margin-bottom: .5rem; }
.steps p { color: var(--ink-2); font-size: 1.02rem; }

.formats { list-style: none; padding: 0; margin: clamp(2.5rem, 5vw, 4rem) 0 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 2.5rem 2rem; }
.formats li { border-top: 2px solid var(--ink); padding-top: 1.25rem; }
.formats h3 { font-size: 1.4rem; margin-bottom: .5rem; display: flex; align-items: baseline; gap: .7rem; }
.formats h3::before { content: ""; flex: none; width: .5em; height: .5em; background: var(--red); }
.formats p { color: var(--ink-2); font-size: 1.02rem; }

/* FAQ en annexe, après le contact : compacte, hors gamme */
.faq-annex { padding-block: clamp(3rem, 6vw, 4.5rem); }
.faq-annex h2 { font-size: 1.6rem; letter-spacing: -0.02em; }
.faq-annex .intro { font-size: 1.02rem; margin-top: .6rem; }
.faq-list { margin-top: 2rem; columns: 2; column-gap: 4rem; }
.faq-annex details { break-inside: avoid; }
.faq-annex summary { font-size: 1.05rem; padding: 1.05rem 0; }
.faq-annex details:last-child { border-bottom: 0; }
.faq-grid { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: 2.5rem 4rem; align-items: start; }
.faq details { border-top: 1px solid var(--rule); }
.faq details:last-child { border-bottom: 1px solid var(--rule); }
.faq summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 1.5rem; padding: 1.35rem 0; font-size: 1.2rem; font-weight: 600; letter-spacing: -0.01em; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary i { flex: none; width: .7rem; height: .7rem; border: 2px solid var(--ink); transition: background-color .2s, border-color .2s; }
.faq details[open] summary i { background: var(--red); border-color: var(--red); }
.faq summary:hover span { text-decoration: underline; text-decoration-color: var(--red); text-underline-offset: .2em; }
.faq details p { color: var(--ink-2); padding: 0 2.5rem 1.6rem 0; max-width: var(--measure); }

.contact { background: var(--ink); color: var(--on-ink); border-top: 0; }
.contact h2 { font-size: clamp(2.6rem, 7vw, 5.6rem); letter-spacing: -0.045em; font-weight: 800; max-width: 12ch; }
.contact p { color: color-mix(in srgb, var(--on-ink) 72%, transparent); max-width: var(--measure); margin-top: 1.5rem; font-size: 1.2rem; }
.contact .actions { margin-top: 2.5rem; }
.contact .btn { background: var(--red); color: #fff; }
.contact .btn:hover { background: var(--on-ink); color: var(--ink); }
.contact .link { color: var(--on-ink); font-weight: 500; }

footer { padding-block: 3rem; color: var(--ink-2); font-size: .98rem; }
.foot { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 2rem 4rem; align-items: flex-start; }
.foot .logo { height: 1.7rem; color: var(--ink); }
.foot nav ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; }
.foot nav a { text-decoration: none; }
.foot nav a:hover { color: var(--ink); }
.why-si { max-width: 30rem; }
.legal { margin-top: 2rem; }
.perf::before { content: " · "; }
.perf { font-variant-numeric: tabular-nums; }

@media (max-width: 980px) {
  .cases { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .faq-grid { grid-template-columns: 1fr; }
  .faq-list { columns: 1; }
  .formats { grid-template-columns: 1fr; }
}
@media (max-width: 820px) {
  .nav ul { display: none; }
  .hero { grid-template-columns: 1fr; }
  .hero-art { width: 100%; margin-top: 2.5rem; }
  .hero-art .hero-mark { width: 100%; }
  .service { grid-template-columns: 1fr; }
  .why { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .bar.has-staff .top .btn { display: none; }
  .bar.has-staff .top { gap: .75rem; }
  .bar.has-staff .nav { min-width: 0; }
  .staffnav { gap: .5rem; min-width: 0; }
  .staffnav svg { height: 1.8rem; flex: none; }
  .staffnav-label { font-size: .85rem; min-width: 0; overflow: hidden; text-overflow: ellipsis; }
  .cases, .steps, .ticks { grid-template-columns: 1fr; }
  .logo { height: 1.8rem; }
  .top .btn { padding: .65rem 1rem; font-size: .95rem; }
}
@media (max-width: 400px) {
  .top { gap: .75rem; }
  .logo { height: 1.6rem; }
  .top .btn { padding: .6rem .8rem; font-size: .9rem; }
}

/* page 404 : la gamme redescend du si à l’ut */
.lost { padding-block: clamp(3rem, 9vw, 7rem) clamp(4rem, 10vw, 8rem); }
.lost .hero-mark { width: min(24rem, 90%); margin-bottom: clamp(2.5rem, 6vw, 4rem); }
.lost h1 { font-size: clamp(2.2rem, 6vw, 4.8rem); max-width: 16ch; }
.lost .lead { margin-bottom: 2rem; }