:root{
    --paper: #E8E9E1;
    --paper-2: #DEDFD5;
    --ink: #15181A;
    --ink-soft: #383B37;
    --indigo: #23324A;
    --indigo-deep: #141B27;
    --brass: #8C6A2C;
    --brass-light: #C9A868;
    --sage: #6E7264;
    --line: #B9BBAC;
    --line-dark: #3B4456;
    --paper-on-dark: #E9E9E1;
    --font-display: "Fraunces", serif;
    --font-body: "Source Serif 4", serif;
    --font-mono: "IBM Plex Mono", monospace;
  }
  *{box-sizing:border-box;}
  html{scroll-behavior:smooth;}
  body{
    margin:0;
    background:var(--paper);
    color:var(--ink);
    font-family:var(--font-body);
    font-size:17px;
    line-height:1.65;
    -webkit-font-smoothing:antialiased;
  }
  ::selection{background:var(--brass); color:var(--paper);}
  a{color:inherit;}
  .wrap{max-width:1080px; margin:0 auto; padding:0 40px;}
  @media(max-width:640px){ .wrap{padding:0 22px;} }

  /* ---------- NAV ---------- */
  header.nav{
    position:sticky; top:0; z-index:50;
    background:rgba(232,233,225,0.92);
    backdrop-filter:blur(6px);
    border-bottom:1px solid var(--line);
  }
  .nav-inner{
    max-width:1080px; margin:0 auto; padding:16px 40px;
    display:flex; align-items:center; justify-content:space-between;
  }
  @media(max-width:640px){ .nav-inner{padding:14px 22px;} }
  .brandmark{
    font-family:var(--font-mono); font-size:14px; letter-spacing:0.18em;
    font-weight:500; text-decoration:none; color:var(--ink);
  }
  .brandmark span{color:var(--brass);}
  nav.links{display:flex; gap:28px; font-family:var(--font-mono); font-size:12.5px; letter-spacing:0.04em;}
  nav.links a{text-decoration:none; color:var(--ink-soft); position:relative; padding-bottom:2px;}
  nav.links a:hover{color:var(--ink);}
  @media(max-width:800px){ nav.links{display:none;} }

  /* ---------- HERO ---------- */
  .hero{
    position:relative; overflow:hidden;
    padding:120px 0 90px;
    border-bottom:1px solid var(--line);
  }
  .hero-watermark{
    position:absolute; top:-40px; left:50%; transform:translateX(-50%);
    font-family:var(--font-display); font-weight:600;
    font-size:clamp(90px, 19vw, 260px);
    color:transparent;
    -webkit-text-stroke:1px rgba(21,24,26,0.09);
    white-space:nowrap; letter-spacing:2px;
    pointer-events:none; user-select:none;
    z-index:0;
  }
  .hero-inner{position:relative; z-index:1; display:grid; grid-template-columns:1.15fr 0.85fr; gap:56px; align-items:end;}
  @media(max-width:900px){ .hero-inner{grid-template-columns:1fr;} }
  .eyebrow{
    font-family:var(--font-mono); font-size:12.5px; letter-spacing:0.16em;
    color:var(--brass); text-transform:uppercase; margin:0 0 22px;
    display:flex; align-items:center; gap:10px;
  }
  .eyebrow::before{content:""; width:22px; height:1px; background:var(--brass); display:inline-block;}
  h1.title{
    font-family:var(--font-display); font-weight:500;
    font-size:clamp(40px, 5.6vw, 68px);
    line-height:1.02; margin:0 0 22px; letter-spacing:-0.01em;
  }
  h1.title em{font-style:italic; color:var(--indigo);}
  p.lede{
    font-size:19px; color:var(--ink-soft); max-width:46ch; margin:0 0 30px;
  }
  .name-provisoire{font-family:var(--font-mono); font-size:12px; color:var(--sage);}

  /* acronym stack */
  .acronym-stack{
    font-family:var(--font-mono); font-size:13px;
    border-left:1px solid var(--line-dark);
    padding-left:0;
  }
  .acronym-stack .row{
    display:grid; grid-template-columns:26px 1fr; gap:14px;
    padding:7px 0 7px 18px; border-top:1px solid var(--line);
    align-items:baseline;
  }
  .acronym-stack .row:first-child{border-top:none;}
  .acronym-stack .letter{color:var(--brass); font-weight:500; font-size:15px;}
  .acronym-stack .word{color:var(--ink-soft);}

  /* ---------- signature: idea-space diagram ---------- */
  .ideaspace{
    margin-top:8px; position:relative;
    background:var(--indigo-deep); border-radius:2px;
    border:1px solid var(--line-dark);
    padding:0;
  }
  .ideaspace svg{display:block; width:100%; height:auto;}
  .ideaspace-caption{
    font-family:var(--font-mono); font-size:11px; color:#8891A3;
    padding:10px 16px 14px; border-top:1px solid var(--line-dark);
    letter-spacing:0.02em;
  }
  .ideaspace-caption b{color:var(--brass-light); font-weight:500;}
  .vec-dot{animation:drift 7s ease-in-out infinite;}
  .vec-dot.d2{animation-delay:-1.4s;}
  .vec-dot.d3{animation-delay:-3.1s;}
  .vec-dot.d4{animation-delay:-4.6s;}
  .vec-dot.d5{animation-delay:-2.2s;}
  @keyframes drift{
    0%,100%{ transform:translate(0,0); }
    50%{ transform:translate(3px,-4px); }
  }
  .fusion-core{animation:pulse 3.2s ease-in-out infinite;}
  @keyframes pulse{
    0%,100%{ opacity:0.55; r:5; }
    50%{ opacity:1; r:7.5; }
  }
  @media (prefers-reduced-motion:reduce){
    .vec-dot, .fusion-core{animation:none;}
  }

  /* ---------- SECTION scaffolding ---------- */
  section{padding:84px 0; border-bottom:1px solid var(--line);}
  section.dark{background:var(--indigo-deep); color:var(--paper-on-dark); border-bottom:none;}
  section.dark .section-label{color:var(--brass-light);}
  section.dark h2{color:var(--paper-on-dark);}
  section.dark .divider{background:var(--line-dark);}
  .section-label{
    font-family:var(--font-mono); font-size:12px; letter-spacing:0.14em;
    text-transform:uppercase; color:var(--brass); margin:0 0 16px;
  }
  h2.section-title{
    font-family:var(--font-display); font-weight:500;
    font-size:clamp(28px,3.4vw,40px); margin:0 0 28px; letter-spacing:-0.01em;
  }
  .divider{height:1px; background:var(--line); margin:0 0 40px; border:none;}
  .lede-block{max-width:62ch; font-size:17.5px; color:var(--ink-soft); margin-bottom:36px;}
  section.dark .lede-block{color:#C9CCC2;}

  /* preambule quote */
  .quote{
    font-family:var(--font-display); font-style:italic; font-weight:400;
    font-size:clamp(21px,2.6vw,28px); line-height:1.5;
    color:var(--indigo); max-width:52ch; margin:0;
  }
  section.dark .quote{color:var(--paper-on-dark);}

  /* vision forms list */
  .forms-grid{display:grid; grid-template-columns:repeat(2,1fr); gap:1px; background:var(--line); border:1px solid var(--line); margin-top:8px;}
  @media(max-width:640px){ .forms-grid{grid-template-columns:1fr;} }
  .forms-grid .cell{background:var(--paper); padding:20px 24px; font-size:15.5px;}
  .forms-grid .cell b{font-family:var(--font-mono); font-weight:500; font-size:12px; color:var(--brass); display:block; margin-bottom:6px; letter-spacing:0.04em;}

  /* mission cards */
  .mission-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:24px;}
  @media(max-width:900px){ .mission-grid{grid-template-columns:repeat(2,1fr);} }
  @media(max-width:520px){ .mission-grid{grid-template-columns:1fr;} }
  .mission-card{border-top:2px solid var(--brass); padding-top:16px;}
  .mission-num{font-family:var(--font-mono); font-size:12px; color:var(--sage);}
  .mission-card h3{font-family:var(--font-display); font-weight:500; font-size:19px; margin:8px 0 10px;}
  .mission-card p{font-size:14.5px; color:var(--ink-soft); margin:0;}

  /* domaine / expansion */
  .expand-cols{display:grid; grid-template-columns:1fr 1fr; gap:56px;}
  @media(max-width:800px){ .expand-cols{grid-template-columns:1fr;} }
  .tag-list{list-style:none; margin:14px 0 0; padding:0; display:flex; flex-wrap:wrap; gap:8px;}
  .tag-list li{
    font-family:var(--font-mono); font-size:12.5px; padding:6px 12px;
    border:1px solid var(--line); border-radius:2px; color:var(--ink-soft);
  }
  .col-label{font-family:var(--font-mono); font-size:12px; letter-spacing:0.1em; text-transform:uppercase; color:var(--sage);}
  .col-title{font-family:var(--font-display); font-size:22px; font-weight:500; margin:8px 0 12px;}
  .expand-cols p{font-size:15px; color:var(--ink-soft); margin:0;}

  /* philosophie */
  .principles{display:grid; grid-template-columns:repeat(5,1fr); gap:1px; background:var(--line-dark); border:1px solid var(--line-dark); margin-top:8px;}
  @media(max-width:900px){ .principles{grid-template-columns:repeat(2,1fr);} }
  @media(max-width:520px){ .principles{grid-template-columns:1fr;} }
  .principles .cell{background:var(--indigo-deep); padding:22px 18px; min-height:150px; display:flex; flex-direction:column; justify-content:space-between;}
  .principles .cell .name{font-family:var(--font-display); font-size:18px; color:var(--brass-light);}
  .principles .cell p{font-size:13.5px; color:#C9CCC2; margin:10px 0 0;}

  /* methodologie steps */
  .steps{position:relative; margin-top:10px;}
  .step{
    display:grid; grid-template-columns:56px 1fr; gap:20px;
    padding:18px 0; border-top:1px solid var(--line);
  }
  .step:first-child{border-top:none;}
  .step .idx{font-family:var(--font-mono); font-size:22px; color:var(--brass); font-weight:500;}
  .step .body h4{font-family:var(--font-display); font-weight:500; font-size:17px; margin:0 0 4px;}
  .step .body p{font-size:14.5px; color:var(--ink-soft); margin:0;}

  /* production / valeurs chips */
  .chip-wrap{display:flex; flex-wrap:wrap; gap:10px; margin-top:10px;}
  .chip{
    font-family:var(--font-mono); font-size:13px; padding:8px 14px;
    background:var(--paper-2); border:1px solid var(--line); border-radius:2px;
  }
  .chip.brass{border-color:var(--brass); color:var(--brass);}

  /* ambition/conclusion */
  .closing{max-width:64ch;}
  .closing p{font-size:17.5px; color:#C9CCC2; margin:0 0 20px;}
  .closing p.big{font-family:var(--font-display); font-style:italic; font-size:24px; color:var(--paper-on-dark); font-weight:400;}

  /* footer */
  footer{padding:64px 0 40px; background:var(--ink); color:var(--paper-on-dark);}
  .footer-grid{display:grid; grid-template-columns:1.2fr 1fr; gap:48px; align-items:start;}
  @media(max-width:800px){ .footer-grid{grid-template-columns:1fr;} }
  .footer-acronym{font-family:var(--font-mono); font-size:13px; line-height:2; color:#9AA08D;}
  .footer-acronym b{color:var(--brass-light); font-weight:500;}
  footer .fname{font-family:var(--font-display); font-size:26px; margin:0 0 8px;}
  footer .fsub{font-family:var(--font-mono); font-size:12px; color:#7D8377;}
  footer .copyline{margin-top:40px; font-family:var(--font-mono); font-size:11.5px; color:#666C5C; border-top:1px solid #2C3128; padding-top:20px;}

  .reveal{opacity:0; transform:translateY(14px); transition:opacity .7s ease, transform .7s ease;}
  .reveal.in{opacity:1; transform:translateY(0);}