/* =========================================================
   SAA BIOMEDICAL SARL — Design System
   Brand: green #2BC50F · blue #1062C8
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Sora:wght@500;600;700;800&family=Inter:wght@400;500;600;700&display=swap');

:root {
  /* Brand */
  --green:        #2BC50F;
  --green-600:    #22A80C;
  --green-700:    #1B8A0A;
  --blue:         #1062C8;
  --blue-600:     #0D53AB;
  --blue-700:     #0A4288;
  --blue-900:     #072F63;

  /* Neutrals */
  --ink:          #0E1B2A;
  --ink-soft:     #33465a;
  --muted:        #64748b;
  --line:         #e3e9f0;
  --paper:        #ffffff;
  --paper-2:      #f5f9fc;
  --paper-3:      #eef4fa;

  /* Effects */
  --radius:       16px;
  --radius-sm:    10px;
  --radius-lg:    26px;
  --shadow-sm:    0 2px 8px rgba(14,27,42,.06);
  --shadow:       0 12px 30px -12px rgba(10,79,166,.22);
  --shadow-lg:    0 30px 60px -20px rgba(10,79,166,.30);
  --ring:         0 0 0 4px rgba(16,98,200,.18);

  --grad-brand:   linear-gradient(120deg, var(--blue) 0%, var(--blue-700) 55%, var(--green-700) 140%);
  --grad-pulse:   linear-gradient(90deg, var(--green), var(--blue));

  --container:    1180px;
  --nav-h:        76px;
}

/* ---------- Reset ---------- */
*,*::before,*::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
h1,h2,h3,h4 { font-family: 'Sora', sans-serif; line-height: 1.12; color: var(--ink); font-weight: 700; }
:focus-visible { outline: none; box-shadow: var(--ring); border-radius: 6px; }

.container { width: min(100% - 2.5rem, var(--container)); margin-inline: auto; }

/* ---------- Reusable eyebrow / heartbeat divider ---------- */
.eyebrow {
  display: inline-flex; align-items: center; gap: .55rem;
  font: 600 .78rem/1 'Inter', sans-serif;
  letter-spacing: .16em; text-transform: uppercase;
  color: var(--blue); margin-bottom: 1rem;
}
.eyebrow::before {
  content: ""; width: 34px; height: 16px; flex: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 60 24'%3E%3Cdefs%3E%3ClinearGradient id='g' x1='0' y1='0' x2='1' y2='0'%3E%3Cstop offset='0' stop-color='%232BC50F'/%3E%3Cstop offset='1' stop-color='%231062C8'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cpath d='M0 12 H16 L20 12 L24 4 L29 20 L33 8 L37 12 H60' fill='none' stroke='url(%23g)' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: center; background-size: contain;
}

/* signature ECG line */
.pulse-rule { display:block; width:100%; height:26px; color: var(--green); opacity:.9; }

/* ---------- Buttons ---------- */
.btn {
  --bg: var(--green); --fg: #fff;
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  padding: .85rem 1.6rem; border-radius: 999px;
  font: 600 .98rem/1 'Inter', sans-serif; cursor: pointer; border: 0;
  background: var(--bg); color: var(--fg);
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
  box-shadow: 0 8px 20px -8px rgba(43,197,15,.5);
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 14px 28px -10px rgba(43,197,15,.6); }
.btn--blue { --bg: var(--blue); box-shadow: 0 8px 20px -8px rgba(16,98,200,.55); }
.btn--blue:hover { box-shadow: 0 14px 28px -10px rgba(16,98,200,.65); }
.btn--ghost {
  background: transparent; color: #fff;
  border: 1.5px solid rgba(255,255,255,.55); box-shadow: none;
}
.btn--ghost:hover { background: rgba(255,255,255,.12); border-color:#fff; }
.btn--outline {
  background: #fff; color: var(--blue); border: 1.5px solid var(--line); box-shadow: var(--shadow-sm);
}
.btn--outline:hover { border-color: var(--blue); color: var(--blue-700); }
.btn--sm { padding: .5rem 1.1rem; font-size: .85rem; }

/* ---------- Header ---------- */
.header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.86);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-container {
  height: var(--nav-h);
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  width: min(100% - 2.5rem, var(--container)); margin-inline: auto;
}
.logo { display: flex; align-items: center; gap: .7rem; }
.logo-icon img { width: 46px; height: 46px; object-fit: contain; }
.company-name { font-family:'Sora',sans-serif; font-weight: 800; font-size: 1.05rem; letter-spacing: -.01em; color: var(--blue-700); }
.company-slogan { font-size: .72rem; color: var(--green-700); font-weight: 600; letter-spacing:.02em; }

.nav-menu { display: flex; align-items: center; gap: .35rem; }
.nav-menu a {
  position: relative; display:inline-block; padding: .55rem .85rem; border-radius: 8px;
  font-weight: 500; font-size: .95rem; color: var(--ink-soft); transition: color .15s, background .15s;
}
.nav-menu a::after {
  content:""; position:absolute; left:.85rem; right:.85rem; bottom:.34rem; height:2px;
  background: var(--grad-pulse); border-radius:2px; transform: scaleX(0); transform-origin:left; transition: transform .22s ease;
}
.nav-menu a:hover { color: var(--blue-700); }
.nav-menu a:hover::after,
.nav-menu a.active::after { transform: scaleX(1); }
.nav-menu a.active { color: var(--blue-700); font-weight: 600; }

.mobile-menu {
  display: none; background: none; border: 0; cursor: pointer;
  width: 42px; height: 42px; border-radius: 10px; font-size: 1.5rem; color: var(--blue-700);
}
.mobile-menu:hover { background: var(--paper-3); }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(1100px 480px at 82% -8%, rgba(43,197,15,.16), transparent 60%),
    radial-gradient(900px 500px at 8% 8%, rgba(16,98,200,.14), transparent 55%),
    var(--grad-brand);
  color: #fff; padding: clamp(4rem, 9vw, 7.5rem) 0 clamp(5rem,10vw,8rem);
}

.hero__slideshow { position:absolute; inset:0; z-index:0; }
.hero__slide {
  position:absolute; inset:0;
  opacity:0; animation: heroSlideFade 36s infinite;
}
.hero__slide img {
  width:100%; height:100%; object-fit:cover;
  filter: saturate(1.05) brightness(.85);
}
.hero__slide:nth-child(1) { animation-delay: 0s; }
.hero__slide:nth-child(2) { animation-delay: 4s; }
.hero__slide:nth-child(3) { animation-delay: 8s; }
.hero__slide:nth-child(4) { animation-delay: 12s; }
.hero__slide:nth-child(5) { animation-delay: 16s; }
.hero__slide:nth-child(6) { animation-delay: 20s; }
.hero__slide:nth-child(7) { animation-delay: 24s; }
.hero__slide:nth-child(8) { animation-delay: 28s; }
.hero__slide:nth-child(9) { animation-delay: 32s; }
@keyframes heroSlideFade {
  0%, 100% { opacity:0; transform: scale(1.06); }
  2% { opacity:1; transform: scale(1); }
  9% { opacity:1; transform: scale(1); }
  11% { opacity:0; transform: scale(1.06); }
}
.hero__overlay {
  position:absolute; inset:0; z-index:1;
  background:
    linear-gradient(100deg, rgba(8,20,46,.9) 0%, rgba(11,44,97,.82) 32%, rgba(16,98,200,.62) 58%, rgba(34,150,20,.5) 100%),
    radial-gradient(1100px 480px at 82% -8%, rgba(43,197,15,.16), transparent 60%),
    radial-gradient(900px 500px at 8% 8%, rgba(16,98,200,.14), transparent 55%);
}
@media (prefers-reduced-motion: reduce) {
  .hero__slide { animation: none; opacity:0; }
  .hero__slide:first-child { opacity:1; }
}

.hero .container { position:relative; z-index:2; }
.hero__grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 3rem; align-items: center; }
.hero .eyebrow { color: #b9f5ac; }
.hero .eyebrow::before { background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 60 24'%3E%3Cpath d='M0 12 H16 L20 12 L24 4 L29 20 L33 8 L37 12 H60' fill='none' stroke='%23b9f5ac' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E"); }
.hero h1 {
  color: #fff; font-weight: 800; font-size: clamp(2.2rem, 5vw, 3.7rem);
  letter-spacing: -.02em; margin-bottom: 1.1rem;
}
.hero h1 .hl { color: #b9f5ac; }
.hero .tagline {
  display:inline-block; font-family:'Sora',sans-serif; font-weight:600; font-style: italic;
  color:#cfe3ff; margin-bottom:1rem;
}
.hero p.lead { font-size: 1.08rem; color: rgba(255,255,255,.9); max-width: 46ch; margin-bottom: 2rem; }
.hero .cta-buttons { display: flex; flex-wrap: wrap; gap: .9rem; }

.hero__card {
  background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.22);
  border-radius: var(--radius-lg); padding: 1.6rem;
  backdrop-filter: blur(6px);
}
.hero__card h3 { color:#fff; font-size:1.05rem; margin-bottom: 1rem; display:flex; align-items:center; gap:.5rem;}
.hero-stats { display:grid; grid-template-columns: repeat(2,1fr); gap: 1rem; }
.hero-stat { background: rgba(255,255,255,.09); border-radius: var(--radius-sm); padding: 1rem; }
.hero-stat b { font-family:'Sora'; font-size:1.55rem; font-weight:800; color:#b9f5ac; display:block; }
.hero-stat span { font-size:.8rem; color: rgba(255,255,255,.82); }

.hero__wave { position:absolute; left:0; right:0; bottom:-1px; line-height:0; color: var(--paper); z-index:2; }

/* ---------- Section scaffolding ---------- */
.section { padding: clamp(3.5rem, 7vw, 6rem) 0; }
.section--tint { background: var(--paper-2); }
.section-head { max-width: 62ch; margin-bottom: 2.8rem; }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head h2 { font-size: clamp(1.7rem, 3.4vw, 2.5rem); letter-spacing: -.02em; margin-bottom: .8rem; }
.section-head p { color: var(--muted); font-size: 1.05rem; }

/* ---------- Cards grid (services / features) ---------- */
.grid { display: grid; gap: 1.4rem; }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.8rem; box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
  position: relative; overflow: hidden;
}
.card::before {
  content:""; position:absolute; inset:0 auto 0 0; width:3px; background: var(--grad-pulse);
  transform: scaleY(0); transform-origin: top; transition: transform .25s ease;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow); border-color: transparent; }
.card:hover::before { transform: scaleY(1); }

/* ---------- Médiathèque (social feeds) ---------- */
.media-card { padding: 0; overflow: visible; }
.media-card:hover { transform: none; box-shadow: var(--shadow-sm); }
.media-card__head {
  display: flex; align-items: center; gap: .9rem; padding: 1.4rem 1.6rem;
  border-bottom: 1px solid var(--line);
}
.media-card__head > i { font-size: 1.6rem; color: var(--blue-700); }
.media-card__head div:nth-child(2) { flex: 1; }
.media-card__head h3 { margin: 0; font-size: 1.05rem; }
.media-card__head span { color: var(--muted); font-size: .88rem; }
.media-card__body { padding: 1.4rem; min-height: 300px; display:flex; justify-content:center; }
.media-note { margin-top: 1.6rem; color: var(--muted); font-size: .88rem; text-align: center; }

.card .ico {
  width: 54px; height: 54px; border-radius: 14px; display:grid; place-items:center;
  font-size: 1.6rem; margin-bottom: 1.1rem;
  background: linear-gradient(135deg, rgba(43,197,15,.14), rgba(16,98,200,.14));
  color: var(--blue-700);
}
.card h3 { font-size: 1.16rem; margin-bottom: .55rem; }
.card p { color: var(--muted); font-size: .96rem; }

/* ---------- About ---------- */
.about__grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 3rem; align-items: center; }
.about__text p { color: var(--ink-soft); margin-bottom: 1rem; }
.stats { display: grid; grid-template-columns: repeat(2,1fr); gap: 1rem; margin-top: 1.8rem; }
.stat {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 1.2rem 1.3rem; box-shadow: var(--shadow-sm);
}
.stat-number { font-family:'Sora'; font-size: 1.8rem; font-weight: 800; color: var(--blue-700); }
.stat-number .u { color: var(--green-600); }
.stat-label { font-size: .82rem; color: var(--muted); }

.about__visual {
  border-radius: var(--radius-lg); min-height: 340px; position: relative; overflow:hidden;
  background:
    radial-gradient(600px 300px at 80% 10%, rgba(43,197,15,.28), transparent 60%),
    var(--grad-brand);
  display: grid; place-items: center; color:#fff; box-shadow: var(--shadow-lg);
}
.about__visual .badge-list { display:grid; gap:.7rem; padding: 2rem; width:100%; }
.about__visual .b {
  display:flex; align-items:center; gap:.8rem; background: rgba(255,255,255,.12);
  border:1px solid rgba(255,255,255,.2); border-radius: 12px; padding:.85rem 1rem; font-weight:600; font-size:.95rem;
}
.about__visual .b .dot { width:34px;height:34px;border-radius:9px; background:rgba(255,255,255,.18); display:grid;place-items:center; font-size:1.1rem;}

/* ---------- Products (home teaser) ---------- */
.prod-card {
  background:#fff; border:1px solid var(--line); border-radius: var(--radius); overflow:hidden;
  box-shadow: var(--shadow-sm); transition: transform .2s, box-shadow .2s;
}
.prod-card:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.prod-card .thumb {
  position:relative; aspect-ratio: 16/10; overflow:hidden; font-size:2.4rem; color:#fff;
  background: linear-gradient(135deg, var(--blue), var(--blue-700));
}
.prod-card .thumb img { width:100%; height:100%; object-fit:cover; display:block; }
.prod-card .thumb i { position:absolute; inset:0; display:grid; place-items:center; }
.prod-card .thumb::after {
  content:""; position:absolute; inset:0; z-index:1; pointer-events:none;
  background: linear-gradient(135deg, rgba(16,98,200,.5), rgba(10,66,136,.5));
}
.prod-card .thumb:has(i)::after { display:none; }
.prod-card:nth-child(2n) .thumb::after { background: linear-gradient(135deg, rgba(34,168,12,.45), rgba(16,98,200,.45)); }
.prod-card:nth-child(3n) .thumb::after { background: linear-gradient(135deg, rgba(10,66,136,.5), rgba(21,102,30,.5)); }
.prod-card .body { padding: 1.3rem 1.4rem 1.6rem; }
.prod-card h3 { font-size: 1.08rem; margin-bottom:.4rem; }
.prod-card p { color: var(--muted); font-size:.92rem; }

/* ---------- CTA band ---------- */
.cta-band {
  background: var(--grad-brand); color:#fff; border-radius: var(--radius-lg);
  padding: clamp(2.2rem,5vw,3.4rem); display:flex; gap:1.5rem; align-items:center; justify-content:space-between; flex-wrap:wrap;
  box-shadow: var(--shadow-lg);
}
.cta-band h2 { color:#fff; font-size: clamp(1.5rem,3vw,2.1rem); }
.cta-band p { color: rgba(255,255,255,.86); margin-top:.4rem; max-width:52ch; }

/* ---------- Contact ---------- */
.contact__grid { display:grid; grid-template-columns: 1fr 1.1fr; gap: 2.6rem; }
.contact-item { display:flex; gap:1rem; align-items:flex-start; margin-bottom:1.2rem; }
.contact-icon {
  width:46px;height:46px;border-radius:12px;flex:0 0 auto; display:grid;place-items:center; font-size:1.2rem;
  background: linear-gradient(135deg, rgba(43,197,15,.15), rgba(16,98,200,.15)); color:var(--blue-700);
}
.contact-item strong { display:block; color:var(--ink); font-size:.98rem; }
.contact-item span { color: var(--muted); font-size:.94rem; }

.form-card { background:#fff; border:1px solid var(--line); border-radius: var(--radius-lg); padding: 2rem; box-shadow: var(--shadow); }
.form-card h3 { margin-bottom: 1.2rem; }
.form-group { margin-bottom: 1.05rem; }
.form-group label { display:block; font-size:.85rem; font-weight:600; color: var(--ink-soft); margin-bottom:.35rem; }
.form-control {
  width:100%; padding:.8rem 1rem; border:1.5px solid var(--line); border-radius: 12px;
  font: inherit; font-size:.95rem; background:#fff; transition: border-color .15s, box-shadow .15s;
}
.form-control:focus { border-color: var(--blue); box-shadow: var(--ring); outline:none; }
textarea.form-control { resize: vertical; min-height: 120px; }

/* ---------- Footer ---------- */
.footer { background: var(--blue-900); color: rgba(255,255,255,.78); padding: 3.5rem 0 1.5rem; }
.footer__grid { display:grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 2rem; margin-bottom: 2.4rem; }
.footer h3 { color:#fff; font-size:1rem; margin-bottom:1rem; }
.footer__brand .company-name { color:#fff; }
.footer__brand p { font-size:.92rem; margin-top:.8rem; }
.footer a { color: rgba(255,255,255,.72); font-size:.93rem; }
.footer a:hover { color:#b9f5ac; }
.footer li { margin-bottom:.5rem; }
.footer__contact p { font-size:.92rem; margin-bottom:.5rem; }
.social-icons { display:flex; gap:.6rem; margin-top:1rem; }
.social-icons a {
  width:40px;height:40px;border-radius:10px; display:grid;place-items:center; font-size:1.1rem;
  background: rgba(255,255,255,.08); color:#fff; transition: background .18s, transform .18s;
}
.social-icons a:hover { background: var(--green-600); transform: translateY(-2px); }
.footer-bottom { border-top:1px solid rgba(255,255,255,.12); padding-top:1.3rem; font-size:.85rem; text-align:center; color: rgba(255,255,255,.6); }

/* ---------- Page hero (subpages) ---------- */
.page-hero {
  background:
    radial-gradient(900px 400px at 85% 0%, rgba(43,197,15,.18), transparent 60%),
    var(--grad-brand);
  color:#fff; padding: clamp(3rem,7vw,5rem) 0; position:relative; overflow:hidden;
}
.page-hero h1 { color:#fff; font-size: clamp(2rem,4.4vw,3rem); margin-bottom:.7rem; }
.page-hero p { color: rgba(255,255,255,.9); max-width: 60ch; font-size:1.05rem; }
.page-hero .eyebrow { color:#b9f5ac;} .page-hero .eyebrow::before{ background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 60 24'%3E%3Cpath d='M0 12 H16 L20 12 L24 4 L29 20 L33 8 L37 12 H60' fill='none' stroke='%23b9f5ac' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E"); }
.breadcrumb { font-size:.85rem; color: rgba(255,255,255,.8); margin-bottom:1rem; }
.breadcrumb a:hover { color:#fff; }

/* ---------- Products page filter ---------- */
.filter-bar { display:flex; flex-wrap:wrap; gap:1rem; align-items:center; justify-content:space-between; margin-bottom:2rem; }
.filter-tabs { display:flex; flex-wrap:wrap; gap:.5rem; }
.filter-tab {
  padding:.55rem 1.1rem; border-radius:999px; border:1.5px solid var(--line); background:#fff;
  font-weight:600; font-size:.9rem; color: var(--ink-soft); cursor:pointer; transition: all .16s;
}
.filter-tab:hover { border-color: var(--blue); color: var(--blue-700); }
.filter-tab.active { background: var(--grad-brand); color:#fff; border-color: transparent; }
.search-bar { position:relative; }
.search-input { padding:.7rem 2.6rem .7rem 1rem; border:1.5px solid var(--line); border-radius:999px; font:inherit; min-width:260px; }
.search-input:focus { border-color: var(--blue); box-shadow: var(--ring); outline:none; }
.search-icon { position:absolute; right:1rem; top:50%; transform:translateY(-50%); color: var(--muted); }

.product-badge {
  position:absolute; top:.8rem; right:.8rem; z-index:2; background:#fff; color: var(--blue-700);
  font-size:.72rem; font-weight:700; padding:.3rem .7rem; border-radius:999px; box-shadow: var(--shadow-sm);
}
.product-category { font-size:.75rem; font-weight:700; letter-spacing:.08em; text-transform:uppercase; color: var(--green-700); margin-bottom:.4rem; }
.features-list { display:grid; gap:.35rem; margin:.6rem 0 1rem; }
.features-list li { position:relative; padding-left:1.4rem; font-size:.9rem; color: var(--ink-soft); }
.features-list li::before { content:"✓"; position:absolute; left:0; color: var(--green-600); font-weight:800; }
.specs-title, .product-features h4 { font-size:.8rem; font-weight:700; text-transform:uppercase; letter-spacing:.06em; color: var(--muted); margin-bottom:.5rem; }
.specs-grid { display:grid; grid-template-columns: repeat(2,1fr); gap:.5rem; margin-bottom:1.1rem; }
.spec-item { background: var(--paper-2); border:1px solid var(--line); border-radius:10px; padding:.6rem .7rem; }
.spec-label { display:block; font-size:.72rem; color: var(--muted); }
.spec-value { font-weight:700; font-size:.9rem; color: var(--ink); }
.product-actions { display:flex; gap:.6rem; flex-wrap:wrap; }
.product-card.hide { display:none; }

/* ---------- Formation timeline ---------- */
.track { display:grid; gap:1.2rem; }
.track-item {
  display:grid; grid-template-columns: auto 1fr; gap:1.2rem; background:#fff; border:1px solid var(--line);
  border-radius: var(--radius); padding:1.5rem; box-shadow: var(--shadow-sm);
}
.track-num {
  font-family:'Sora'; font-weight:800; font-size:1.1rem; width:52px;height:52px;border-radius:14px;
  display:grid;place-items:center; color:#fff; background: var(--grad-brand);
}

/* ---------- Reveal on scroll ---------- */
.reveal { opacity:0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity:1; transform:none; }

/* ---------- Back to top ---------- */
.back-to-top {
  position: fixed; bottom: 28px; right: 28px; z-index: 90;
  width:50px;height:50px;border-radius:50%; border:0; cursor:pointer;
  background: var(--grad-brand); color:#fff; font-size:1.3rem; display:grid;place-items:center;
  box-shadow: var(--shadow); opacity:0; visibility:hidden; transform: translateY(10px);
  transition: opacity .25s, transform .25s, visibility .25s;
}
.back-to-top.show { opacity:1; visibility:visible; transform:none; }
.back-to-top:hover { transform: translateY(-3px); }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .grid--3, .grid--4 { grid-template-columns: repeat(2,1fr); }
  .hero__grid, .about__grid, .contact__grid { grid-template-columns: 1fr; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 760px) {
  .nav-menu {
    position: fixed; inset: var(--nav-h) 0 auto 0;
    flex-direction: column; align-items: stretch; gap:0;
    background:#fff; border-bottom:1px solid var(--line);
    padding:.5rem 1rem 1rem; box-shadow: var(--shadow);
    transform: translateY(-140%); transition: transform .28s ease; z-index: 99;
  }
  .nav-menu.active { transform: translateY(0); }
  .nav-menu a { padding:.85rem .6rem; border-radius:10px; }
  .nav-menu a::after { display:none; }
  .nav-menu a:hover, .nav-menu a.active { background: var(--paper-3); }
  .mobile-menu { display:grid; place-items:center; }
  .grid--3, .grid--4, .grid--2 { grid-template-columns: 1fr; }
  .stats, .hero-stats, .specs-grid { grid-template-columns: repeat(2,1fr); }
  .footer__grid { grid-template-columns: 1fr; }
  .company-slogan { display:none; }
  .cta-band { flex-direction: column; align-items:flex-start; }
  .track-item { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .reveal { opacity:1; transform:none; }
}