:root{
    --paper:#EFF2EF;
    --paper-raised:#F8FAF8;
    --ink:#16211F;
    --ink-soft:#4B5854;
    --ink-faint:#7C8985;
    --rule:#CBD4CE;
    --rule-soft:#DEE4E0;
    --rust:#A8451F;
    --rust-dark:#8A3818;
    --rust-tint:#F5E6DD;
    --verdi:#3E6358;
    --verdi-tint:#E4ECE8;
    --steel:#2C4A63;
    --white:#FFFFFF;
    --shadow: 0 1px 2px rgba(22,33,31,0.06), 0 8px 24px -12px rgba(22,33,31,0.15);
  }
  *{box-sizing:border-box;}
  html{scroll-behavior:smooth;}
  @media (prefers-reduced-motion: reduce){
    html{scroll-behavior:auto;}
    *{animation-duration:0.001ms !important; transition-duration:0.001ms !important;}
  }
  body{
    margin:0;
    background:var(--paper);
    color:var(--ink);
    font-family:'Open Sans',sans-serif;
    font-size:16.5px;
    line-height:1.6;
    -webkit-font-smoothing:antialiased;
  }
  .wrap{max-width:840px; margin:0 auto; padding:0 28px;}

  /* ---------- Top mast ---------- */
  .mast{
    border-bottom:1px solid var(--rule);
    padding:16px 0;
  }
  .mast .wrap{display:flex; align-items:center; justify-content:space-between; gap:16px; flex-wrap:wrap;}
  .mast-brand{color:var(--ink-soft); font-family:'Open Sans',sans-serif; font-size:13.5px; letter-spacing:.02em; text-transform:none; display:flex; align-items:center; gap:6px;}
  .mast-brand::before{content:"←"; color:var(--rust); font-weight:700; font-size:15px;}
  .mast-brand strong{color:var(--ink); font-weight:600;}
  .mast-brand a{color:var(--rust); text-decoration:none; font-weight:600; border-bottom:1px solid transparent; transition:border-color .15s ease;}
  .mast-brand a:hover{border-color:var(--rust);}
  .mast-tag{
    font-family:'Open Sans',sans-serif;
    font-size:11.5px;
    letter-spacing:.05em;
    color:var(--verdi);
    border:1px solid var(--verdi);
    border-radius:100px;
    padding:4px 12px;
  }

  /* ---------- Hero ---------- */
  .hero{padding:56px 0 0;}
  .eyebrow{
    font-family:'Open Sans',sans-serif;
    font-size:12.5px;
    letter-spacing:.08em;
    text-transform:uppercase;
    color:var(--rust);
    display:flex;
    align-items:center;
    gap:10px;
    margin-bottom:18px;
  }
  .eyebrow::before{
    content:"";
    width:26px; height:1px; background:var(--rust);
    display:inline-block;
  }
  h1.title{
    font-family:'Open Sans', sans-serif;
   
    font-weight:600;
    font-size:clamp(2.1rem, 4.4vw, 3.15rem);
    line-height:1.06;
    letter-spacing:-0.01em;
    margin:0 0 22px;
    color:var(--ink);
  }
  .lead{
    font-size:14px;
    color:var(--ink-soft);    
  }
  .lead p{margin:0 0 14px;}
  .lead p:last-child{margin-bottom:0;}

  .hero-photo{
    margin-top:34px;
    position:relative;
    border-radius:2px;
    overflow:hidden;
    aspect-ratio: 16/6;
  }
  .hero-photo img{
    width:100%; height:100%; object-fit:cover; display:block;
    filter: grayscale(28%) saturate(88%) contrast(102%);
  }
  .hero-photo::after{
    content:"";
    position:absolute; inset:0;
    background: linear-gradient(100deg, rgba(62,99,88,0.34), rgba(168,69,31,0.12) 55%, rgba(22,33,31,0) 78%);
    mix-blend-mode:multiply;
  }
  .hero-photo::before{
    content:"FIG. 01 — LABORATORIO DE MECÁNICA DE MATERIALES";
    position:absolute; left:14px; bottom:12px;
    font-family:'Open Sans',sans-serif;
    font-size:10.5px; letter-spacing:.05em;
    color:#fff;
    background:rgba(22,33,31,0.55);
    padding:4px 9px;
    z-index:2;
    border-radius:2px;
  }

  /* ---------- Persona selector ---------- */
  .persona-bar{
    margin:44px 0 8px;
    padding:22px 0 26px;
    border-top:1px solid var(--rule);
  }
  .persona-label{
    font-family:'Open Sans',sans-serif;
    font-size:12px;
    letter-spacing:.06em;
    text-transform:uppercase;
    color:var(--ink-faint);
    margin-bottom:14px;
  }
  .persona-pills{
    display:flex; gap:10px; flex-wrap:wrap;
  }
  .pill{
    display:flex; align-items:center; gap:8px;
    background:var(--white);
    border:1px solid var(--rule);
    border-radius:100px;
    padding:9px 16px 9px 10px;
    font-size:14px;
    color:var(--ink);
    text-decoration:none;
    cursor:pointer;
    transition: border-color .18s ease, background .18s ease, transform .18s ease;
  }
  .pill:hover{border-color:var(--rust); transform:translateY(-1px);}
  .pill .code{
    font-family:'Open Sans',sans-serif;
    font-size:11px; font-weight:600;
    background:var(--verdi);
    color:#fff;
    padding:3px 6px;
    border-radius:4px;
    letter-spacing:.02em;
  }

  /* ---------- Accordion group ---------- */
  .content-head{
    display:flex; align-items:baseline; justify-content:space-between;
    margin:52px 0 4px;
    gap:12px; flex-wrap:wrap;
  }
  .section-kicker{
    font-family:'Open Sans',sans-serif;
    font-size:12px; letter-spacing:.07em; text-transform:uppercase;
    color:var(--ink-faint);
  }
  .toggle-all{
    font-family:'Open Sans',sans-serif;
    font-size:12px; letter-spacing:.03em;
    color:var(--steel);
    background:none; border:none; cursor:pointer;
    padding:4px 0;
    text-decoration:underline;
    text-underline-offset:3px;
  }

  .inv-accordion{margin-top:14px;}
  details.acc-item{
    border-bottom:1px solid var(--rule);
  }
  details.acc-item:first-child{border-top:1px solid var(--rule);}
  details.acc-item > summary{
    list-style:none;
    display:flex;
    align-items:center;
    gap:16px;
    padding:20px 4px;
    cursor:pointer;
    -webkit-tap-highlight-color:transparent;
  }
  details.acc-item > summary::-webkit-details-marker{display:none;}
  .acc-num{
    font-family:'Open Sans',sans-serif;
    font-size:13px;
    color:var(--rust);
    min-width:22px;
  }
  .acc-title{
    font-family:'Open Sans', sans-serif;
    font-weight:500;
    font-size:14px;
    color:var(--ink);
    flex:1;
  }
  .acc-chev{
    width:11px; height:11px;
    border-right:1.5px solid var(--ink-faint);
    border-bottom:1.5px solid var(--ink-faint);
    transform:rotate(45deg);
    transition:transform .25s ease;
    flex-shrink:0;
    margin-right:2px;
  }
  details[open] > summary .acc-chev{transform:rotate(-135deg);}
  .acc-body{
    padding:2px 4px 30px 38px;    
    animation: fade-in .22s ease;
  }
  @keyframes fade-in{from{opacity:0; transform:translateY(-4px);} to{opacity:1; transform:translateY(0);}}
  .acc-body p{margin:0 0 13px;}
  .acc-body ul{margin:0 0 13px; padding-left:20px;}
  .acc-body li{margin-bottom:6px;}
  .acc-body strong{ font-weight:600;}
  .acc-body a{color:var(--steel);}

  /* nested sub-accordion (persona items) */
  .sub-accordion{display:flex; flex-direction:column; gap:0;}
  details.sub-item{
    
    border:1px solid var(--rule-soft);
   
    margin-bottom:10px;
  }
  details.sub-item > summary{
    list-style:none;
    display:flex; align-items:center; gap:12px;
    padding:13px 16px;
    cursor:pointer;
  }
  details.sub-item > summary::-webkit-details-marker{display:none;}
  .persona-code{
    font-family:'Open Sans',sans-serif;
    font-size:11px; font-weight:600;
    background:var(--verdi-tint);
    color:var(--verdi);
    padding:3px 7px;
    border-radius:4px;
  }
  .sub-title{font-weight:600; font-size:12px; color:var(--ink); flex:1;}
  .sub-item .acc-body{padding:0 16px 18px 16px; font-size:14px;}

  /* tool grid */
  .tool-grid{
    display:grid;
    grid-template-columns:repeat(2, 1fr);
    gap:10px;
    margin-bottom:14px;
  }
  .tool-card{

    border:1px solid var(--rule-soft);
    border-left:2px solid var(--verdi);
    padding:14px 16px;
  }
  .tool-name{font-weight:600; color:var(--ink); margin:0 0 4px; font-size:.95rem;}
  .tool-desc{margin:0; font-size:.92rem; color:var(--ink-soft);}
  .tool-tail{font-size:.94rem; font-style:italic; color:var(--ink-faint);}
  .tool-tail p{margin:0;}

  .infra-subgrid{display:flex; flex-direction:column; gap:20px; margin-bottom:6px;}
  .infra-lead{margin-bottom:22px; padding-bottom:20px; border-bottom:1px solid var(--rule-soft);}
  .infra-lead p{margin:0;}
  .infra-sub-title{
    font-family:'Open Sans',sans-serif;
    font-size:12px; letter-spacing:.04em; text-transform:uppercase;
    color:var(--verdi); margin:0 0 8px; font-weight:600;
  }
  .infra-sub p{margin:0 0 10px;}
  .infra-sub ul{margin:0 0 10px; padding-left:20px;}


  .two-col{display:grid; grid-template-columns:1fr 1fr; gap:30px;}
  .col-label{
    font-family:'Open Sans',sans-serif;
    font-size:11.5px; letter-spacing:.04em; text-transform:uppercase;
    color:var(--verdi); margin:0 0 10px;
  }

  /* ---------- Admisión callout ---------- */
  .admision{
    margin:56px 0 0;
    border:1px solid #E4C3AF;
    padding:28px 30px;
    position:relative;
  }
  .admision .section-kicker{color:var(--rust-dark);}
  .admision h3{
    font-family:'Open Sans', sans-serif; font-weight:600; font-size:13px;
    margin:6px 0 14px; color:var(--rust-dark);
  }
  .admision p{margin:0 0 12px; color:#5A3524;}
  .admision-link{
    display:inline-flex; align-items:center; gap:8px;
    font-family:'Open Sans',sans-serif;
    font-size:13px;
    color:var(--rust-dark);
    background:#fff;
    border:1px solid var(--rust);
    padding:9px 16px;
    border-radius:100px;
    text-decoration:none;
    margin-top:4px;
  }
  .admision-link:hover{background:var(--rust); color:#fff;}
  .admision-link::after{content:"→"; transition:transform .15s ease;}
  .admision-link:hover::after{transform:translateX(3px);}

  /* ---------- CTA cards ---------- */
  .cta-head{margin:60px 0 4px;}
  .cta-grid{
    display:grid;
    grid-template-columns:repeat(2, 1fr);
    gap:14px;
    margin-top:16px;
  }
  .cta-card{
    background:var(--white);
    border:1px solid var(--rule);
    padding:20px 22px;
    box-shadow:var(--shadow);
    transition: transform .18s ease, border-color .18s ease;
  }
 
  .cta-code{
    font-family:'Open Sans',sans-serif;
    font-size:11px; font-weight:600;
    background:var(--verdi);
    color:#fff;
    padding:3px 7px;
    display:inline-block;
    margin-bottom:10px;
  }
  .cta-card h4{
    font-family:'Open Sans', sans-serif; font-weight:600; font-size:13px;
    margin:0 0 8px; color:var(--ink);
	line-height: 32px;
  }
  .cta-body{font-size:.92rem; color:var(--ink-soft);}
  .cta-body p{margin:0;}
  .cta-body a{color:var(--steel); font-weight:500;}

  /* ---------- Contact ---------- */
  .contact{
    margin:60px 0 90px;
    padding-top:26px;
    border-top:1px solid var(--rule);
    display:flex;
    justify-content:space-between;
    align-items:flex-end;
    flex-wrap:wrap;
    gap:24px;
  }
  .contact-people p{margin:0 0 2px;}
  .contact-people strong{font-family:'Open Sans', sans-serif; font-size:14px; font-weight:600;}
  .contact-people a{color:var(--steel); font-size:14px;}
  .contact-people > p{margin-bottom:16px;}
  .back-top{
    font-family:'Open Sans',sans-serif;
    font-size:14px; color:var(--ink-faint);
    text-decoration:none;
    border-bottom:1px solid var(--rule);
    padding-bottom:2px;
  }

  footer.foot{
    background:var(--ink);
    color:#B9C4BE;
    padding:20px 0;
    font-family:'Open Sans',sans-serif;
    font-size:11.5px;
    letter-spacing:.03em;
  }
  footer.foot .wrap{display:flex; justify-content:space-between; flex-wrap:wrap; gap:8px;}

  @media (max-width:640px){
    .wrap{padding:0 20px;}
    .hero{padding-top:38px;}
    .tool-grid{grid-template-columns:1fr;}
    .two-col{grid-template-columns:1fr;}
    .cta-grid{grid-template-columns:1fr;}
    .acc-body{padding-left:26px;}
    .contact{flex-direction:column; align-items:flex-start;}
    .hero-photo::before{
      font-size:9px; max-width:78%; line-height:1.35;
      white-space:normal; right:14px; left:14px;
    }
  }