/* =============================================================
   BlancoDataLab — marketing site
   Design language mirrors friesgroupe.blancodatalab.de login page.
   ============================================================= */

:root {
  --navy-0:   #0a1733;
  --navy-1:   #0f1e40;
  --navy-2:   #1a3060;
  --navy-3:   #1e4080;
  --accent:   #2563eb;
  --accent-d: #1d4ed8;
  --text:     #1a2235;
  --muted:    #5c6b85;
  --rule:     #e3e9f3;
  --soft:     #f4f7fb;
  --soft-2:   #eef3fa;
  --white:    #ffffff;
  --yellow:   #ffd54a;
  --green:    #1e7e4d;
  --red:      #a02828;
  --shadow-lg: 0 22px 60px rgba(8,16,40,.18);
  --shadow-md: 0 10px 30px rgba(8,16,40,.10);
  --shadow-sm: 0 2px 8px rgba(8,16,40,.06);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Inter", -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 16px; line-height: 1.6; color: var(--text);
  background: var(--white); overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
a:hover { color: var(--accent-d); }

/* ─── Layout ───────────────────────────────────────────────── */
.container         { max-width: 1240px; margin: 0 auto; padding: 0 24px; }
.container-narrow  { max-width: 980px;  margin: 0 auto; padding: 0 24px; }

.section            { padding: 96px 0; position: relative; }
.section-light      { background: var(--white); }
.section-dark       { background: linear-gradient(135deg, var(--navy-1) 0%, var(--navy-2) 40%, var(--navy-3) 70%, var(--navy-2) 100%); color: #fff; }
.section-references { background: var(--soft); }

/* ─── Section head ─────────────────────────────────────────── */
.section-head { max-width: 820px; margin: 0 auto 56px; text-align: center; }
.eyebrow {
  display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: .14em;
  color: var(--accent-d); text-transform: uppercase; margin-bottom: 14px;
  padding: 6px 14px; border-radius: 999px; background: rgba(37,99,235,.08);
}
.eyebrow-light { color: #cfd9ef; background: rgba(255,255,255,.10); }
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.02em; color: var(--navy-1); font-weight: 800; }
h2 { font-size: clamp(28px, 3.4vw, 44px); margin-bottom: 18px; }
h3 { font-size: 20px; margin-bottom: 10px; font-weight: 700; }
h4 { font-size: 16px; font-weight: 700; }
.h-light { color: #fff; }
h2 em, h3 em { font-style: italic; font-weight: 800; color: var(--accent); }
.section-dark h2 em { color: var(--yellow); }
.section-sub {
  font-size: 17px; color: var(--muted); margin-top: 8px; line-height: 1.65;
}
.section-sub-light { color: #cfd9ef; }

/* ─── Buttons ──────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 11px 22px; border-radius: 10px; border: 1.5px solid transparent;
  font-family: inherit; font-size: 14px; font-weight: 600; letter-spacing: .01em;
  cursor: pointer; transition: transform .12s, background .18s, box-shadow .18s, border-color .18s;
  white-space: nowrap;
}
.btn-sm  { padding: 8px  16px; font-size: 13px; }
.btn-lg  { padding: 14px 26px; font-size: 15px; }
.btn-block { width: 100%; margin-top: 6px; }
.btn-primary { background: var(--accent-d); color: #fff; box-shadow: 0 4px 14px rgba(29,78,216,.35); }
.btn-primary:hover { background: #1e40af; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(29,78,216,.45); color: #fff; }
.btn-ghost { background: rgba(255,255,255,.10); color: #fff; border-color: rgba(255,255,255,.25); }
.btn-ghost:hover { background: rgba(255,255,255,.18); border-color: rgba(255,255,255,.45); color:#fff; }
.section-light .btn-ghost { color: var(--navy-1); background: transparent; border-color: var(--rule); }
.section-light .btn-ghost:hover { background: var(--soft); border-color: var(--accent); color: var(--accent-d); }

/* ─── Navigation ───────────────────────────────────────────── */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 32px;
  background: rgba(15,30,64,.85); backdrop-filter: blur(10px) saturate(1.1);
  border-bottom: 1px solid rgba(255,255,255,.06);
  color: #fff;
}
.nav-brand { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.nav-brand-name { font-size: 18px; font-weight: 600; letter-spacing: -.01em; color: #fff; }
.nav-brand-name strong { font-weight: 800; }

/* Official BlancoDataLab logo asset (dark variant — has its own navy plate baked in) */
.nav-logo-img    { height: 48px; width: auto; display: block; }
.footer-logo-img { height: 56px; width: auto; display: block; margin-bottom: 14px; }
.nav-links { display: flex; gap: 28px; }
.nav-links a {
  font-size: 14px; font-weight: 500; color: rgba(255,255,255,.85);
  transition: color .15s;
}
.nav-links a:hover { color: #fff; }
.nav-cta { display: flex; align-items: center; gap: 14px; }

.lang-toggle {
  display: inline-flex; align-items: center; gap: 4px;
  background: rgba(255,255,255,.10); border: 1px solid rgba(255,255,255,.20);
  color: #fff; font-family: inherit; font-size: 12px; font-weight: 700;
  border-radius: 999px; padding: 4px 6px; cursor: pointer; letter-spacing: .04em;
}
.lang-toggle span {
  display: inline-block; padding: 3px 9px; border-radius: 999px;
  transition: background .18s, color .18s;
}
.lang-toggle .lang-on  { background: #fff; color: var(--navy-1); }
.lang-toggle .lang-off { color: rgba(255,255,255,.7); }
html.lang-en .lang-toggle .lang-on  { background: transparent; color: rgba(255,255,255,.7); }
html.lang-en .lang-toggle .lang-off { background: #fff; color: var(--navy-1); }

.nav-burger {
  display: none; flex-direction: column; gap: 4px; background: transparent;
  border: 0; padding: 8px; cursor: pointer;
}
.nav-burger span { display: block; width: 22px; height: 2px; background: #fff; border-radius: 2px; }

/* ─── Hero ─────────────────────────────────────────────────── */
.hero { position: relative; min-height: 92vh; padding: 130px 0 80px;
        color: #fff; overflow: hidden; }
.hero-bg {
  position: absolute; inset: 0;
  background: linear-gradient(135deg, var(--navy-1) 0%, var(--navy-2) 40%, var(--navy-3) 70%, var(--navy-2) 100%);
}
.hero-bg::before {
  content: ""; position: absolute; right: -15%; top: -20%; width: 70%; height: 120%;
  background: linear-gradient(135deg, transparent 30%, rgba(255,255,255,.04) 60%, transparent 80%);
  transform: rotate(-15deg);
}
.hero-bg::after {
  content: ""; position: absolute; right: 6%; top: 8%; width: 380px; height: 380px;
  border: 1.5px solid rgba(100,160,220,.18); border-radius: 50%;
}
.constellation { position: absolute; inset: 0; z-index: 1; pointer-events: none; }

.hero-grid {
  position: relative; z-index: 2;
  display: grid; grid-template-columns: 1.1fr 1fr; gap: 60px; align-items: center;
}
.hero-eyebrow {
  display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: .14em;
  color: #b0c8ec; text-transform: uppercase; margin-bottom: 22px;
  padding: 6px 14px; border-radius: 999px;
  background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.15);
}
.hero-title {
  font-size: clamp(36px, 5.2vw, 64px); font-weight: 800; letter-spacing: -0.03em;
  color: #fff; line-height: 1.08; margin-bottom: 22px;
}
.hero-title em { font-style: italic; color: var(--yellow); font-weight: 800; }
.hero-sub {
  font-size: 17px; color: rgba(220,230,250,.85); line-height: 1.65;
  max-width: 560px; margin-bottom: 32px;
}
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 56px; }
.hero-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  padding-top: 32px; border-top: 1px solid rgba(255,255,255,.10);
}
.stat-num { font-size: 22px; font-weight: 800; color: #fff; letter-spacing: -.02em; }
.stat-label { font-size: 12px; color: rgba(180,210,245,.8); margin-top: 4px; font-weight: 500; }

/* Hero preview (stylized dashboard) */
.hero-preview { position: relative; z-index: 2; }
.preview-card {
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.12);
  border-radius: 16px; overflow: hidden; backdrop-filter: blur(8px);
  box-shadow: 0 30px 60px rgba(0,0,0,.35);
}
.preview-head {
  padding: 12px 16px; background: rgba(0,0,0,.18); border-bottom: 1px solid rgba(255,255,255,.08);
  display: flex; align-items: center; gap: 12px;
}
.preview-dots { display: flex; gap: 6px; }
.preview-dots span { width: 10px; height: 10px; border-radius: 50%; background: rgba(255,255,255,.30); }
.preview-dots span:nth-child(1) { background: #ff5f57; }
.preview-dots span:nth-child(2) { background: #ffbd2e; }
.preview-dots span:nth-child(3) { background: #27c93f; }
.preview-title { font-size: 12px; color: rgba(255,255,255,.7); font-weight: 500; }
.preview-body { padding: 20px 22px; }
.preview-kpis { display: grid; grid-template-columns: repeat(3,1fr); gap: 12px; margin-bottom: 20px; }
.kpi {
  background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.08);
  border-radius: 10px; padding: 12px 14px;
}
.kpi-lab { font-size: 10px; text-transform: uppercase; letter-spacing: .08em; color: rgba(255,255,255,.55); font-weight: 600; }
.kpi-val { font-size: 22px; font-weight: 800; color: #fff; margin: 4px 0 2px; letter-spacing: -.01em; }
.kpi-delta { font-size: 11px; font-weight: 600; }
.kpi-delta.up   { color: #5bd084; }
.kpi-delta.down { color: #f9b870; }
.preview-chart {
  display: grid; grid-template-columns: repeat(8,1fr); gap: 8px;
  height: 90px; align-items: end; margin-bottom: 18px;
  padding: 12px; background: rgba(255,255,255,.04); border-radius: 10px;
}
.bar {
  background: linear-gradient(180deg, rgba(140,190,240,.95), rgba(80,140,220,.65));
  border-radius: 4px 4px 0 0; transition: height .3s;
}
.preview-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  font-size: 11px; padding: 4px 10px; border-radius: 999px; font-weight: 600;
  background: rgba(255,255,255,.10); color: rgba(255,255,255,.85);
  border: 1px solid rgba(255,255,255,.12);
}
.tag.tag-blue   { background: rgba(80,140,220,.18); color: #b3d2ff; border-color: rgba(80,140,220,.30); }
.tag.tag-green  { background: rgba(91,208,132,.18); color: #b3eecb; border-color: rgba(91,208,132,.30); }
.tag.tag-orange { background: rgba(249,184,112,.18); color: #ffd3a3; border-color: rgba(249,184,112,.30); }

/* ─── Trust strip / industries ticker ──────────────────────── */
.trust-strip {
  background: var(--navy-0); color: #cfd9ef;
  padding: 24px 0; overflow: hidden; position: relative;
}
.trust-label-text {
  text-align: center; font-size: 12px; font-weight: 600; letter-spacing: .14em;
  text-transform: uppercase; color: rgba(207,217,239,.55); margin-bottom: 12px;
}
.trust-ticker { overflow: hidden; mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent); }
.trust-ticker-row {
  display: inline-flex; gap: 32px; white-space: nowrap;
  animation: marquee 50s linear infinite;
  font-size: 15px; font-weight: 600; color: #d4dfee;
}
.trust-ticker-row span:nth-child(odd)  { color: #fff; }
.trust-ticker-row span:nth-child(even) { color: rgba(255,255,255,.40); padding: 0 4px; }
@keyframes marquee {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

/* ─── About: 3 pillar cards ────────────────────────────────── */
.cards-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 22px; }
.cards-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: 22px; }

.card-pillar, .card-service {
  background: var(--white); border: 1px solid var(--rule);
  border-radius: 16px; padding: 28px 26px;
  transition: transform .2s, box-shadow .2s, border-color .2s;
}
.card-pillar:hover, .card-service:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(37,99,235,.30);
}
.pillar-icon, .service-emoji { font-size: 28px; margin-bottom: 16px; }
.card-pillar h3, .card-service h3 { color: var(--navy-1); margin-bottom: 8px; }
.card-pillar p,  .card-service p  { color: var(--muted); font-size: 14.5px; line-height: 1.6; }

.section-dark .card-service {
  background: rgba(255,255,255,.05); border-color: rgba(255,255,255,.10); color: #fff;
}
.section-dark .card-service h3 { color: #fff; }
.section-dark .card-service p  { color: rgba(220,230,250,.78); }
.section-dark .card-service:hover { border-color: rgba(255,255,255,.30); }

/* ─── Numbers band ─────────────────────────────────────────── */
.numbers-band {
  margin-top: 64px; background: var(--soft);
  border-radius: 18px; padding: 36px 32px; border: 1px solid var(--rule);
}
.numbers-band h3 { color: var(--navy-1); text-align: center; margin-bottom: 22px; font-size: 17px;
                   letter-spacing: .04em; text-transform: uppercase; font-weight: 700; }
.numbers-grid {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px;
}
.number { text-align: center; }
.number-val { font-size: 28px; font-weight: 800; color: var(--navy-1); letter-spacing: -.02em; }
.number-lab { font-size: 12px; color: var(--muted); margin-top: 4px; font-weight: 500; }

/* ─── Solutions ────────────────────────────────────────────── */
.solutions-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 22px; }
.solution-card {
  background: var(--white); border: 1px solid var(--rule); border-radius: 18px;
  padding: 30px; position: relative; transition: box-shadow .2s, transform .2s, border-color .2s;
}
.solution-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: rgba(37,99,235,.30); }
.solution-flagship   { border: 2px solid var(--accent); box-shadow: 0 12px 36px rgba(37,99,235,.15); }
.solution-badge {
  position: absolute; top: 18px; right: 18px;
  font-size: 11px; font-weight: 700; letter-spacing: .04em;
  padding: 4px 10px; border-radius: 999px;
  background: var(--soft-2); color: var(--accent-d);
}
.solution-badge-flagship { background: var(--accent); color: #fff; }
.solution-icon { font-size: 32px; margin-bottom: 14px; }
.solution-card h3 { color: var(--navy-1); margin-bottom: 4px; font-size: 22px; }
.solution-sub { font-size: 13px; color: var(--muted); margin-bottom: 14px; font-weight: 500; }
.solution-card > p { color: var(--text); font-size: 14.5px; line-height: 1.6; margin-bottom: 18px; }
.solution-features { list-style: none; padding: 0; margin: 0 0 22px; }
.solution-features li {
  font-size: 13.5px; color: var(--text); padding: 7px 0 7px 26px;
  border-top: 1px solid var(--soft-2); position: relative;
}
.solution-features li::before {
  content: "✓"; position: absolute; left: 0; top: 7px;
  width: 18px; height: 18px; border-radius: 50%;
  background: rgba(37,99,235,.10); color: var(--accent-d);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 11px; font-weight: 800;
}
.solution-link {
  display: inline-block; font-size: 14px; font-weight: 700; color: var(--accent-d);
  border-bottom: 1.5px solid transparent; transition: border-color .15s, color .15s;
}
.solution-link:hover { border-color: var(--accent-d); color: var(--accent-d); }

/* ─── Case study ───────────────────────────────────────────── */
.case {
  background: var(--white); border: 1px solid var(--rule); border-radius: 20px;
  display: grid; grid-template-columns: 360px 1fr; gap: 0; overflow: hidden;
  box-shadow: var(--shadow-md);
}
.case-meta {
  background: linear-gradient(160deg, var(--soft) 0%, var(--soft-2) 100%);
  padding: 36px 32px; border-right: 1px solid var(--rule);
}
.case-customer { display: flex; align-items: center; gap: 14px; margin-bottom: 26px; }
.case-logo {
  width: 56px; height: 56px; border-radius: 14px;
  background: #fff; border: 1px solid var(--rule);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 26px; font-weight: 900; color: var(--navy-1);
}
.case-customer-name { font-size: 17px; font-weight: 700; color: var(--navy-1); }
.case-customer-sub  { font-size: 12px; color: var(--muted); margin-top: 2px; }
.case-stats { list-style: none; }
.case-stats li {
  padding: 14px 0; border-top: 1px solid var(--rule);
  display: flex; flex-direction: column; gap: 2px;
}
.case-stats li:first-child { border-top: 0; padding-top: 0; }
.case-stats li b { font-size: 24px; color: var(--accent-d); font-weight: 800; letter-spacing: -.02em; }
.case-stats li span { font-size: 12.5px; color: var(--muted); }

.case-body { padding: 36px 36px; }
.case-body h3 { color: var(--navy-1); font-size: 14px; text-transform: uppercase; letter-spacing: .08em;
                margin: 20px 0 6px; font-weight: 700; }
.case-body h3:first-child { margin-top: 0; }
.case-body p { color: var(--text); font-size: 15px; line-height: 1.65; }

/* ─── References ───────────────────────────────────────────── */
.ref-headline {
  display: flex; align-items: center; gap: 22px; justify-content: center;
  margin: 0 auto 40px; max-width: 720px; padding: 22px 28px;
  background: var(--white); border: 1px solid var(--rule); border-radius: 18px; box-shadow: var(--shadow-sm);
}
.ref-big { font-size: 64px; font-weight: 900; color: var(--accent-d); line-height: 1; letter-spacing: -.04em; }
.ref-big-line { font-weight: 700; color: var(--navy-1); font-size: 15px; }
.ref-big-sub  { font-size: 13px; color: var(--muted); margin-top: 4px; }
.ref-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 18px; }
.ref-card {
  background: var(--white); border: 1px solid var(--rule); border-radius: 16px;
  padding: 22px; text-align: center; transition: box-shadow .2s, transform .2s, border-color .2s;
}
.ref-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-sm); border-color: rgba(37,99,235,.30); }
.ref-flag { font-size: 20px; }
.ref-emoji { font-size: 32px; margin: 8px 0; }
.ref-card h4 { color: var(--navy-1); font-size: 17px; margin-bottom: 4px; }
.ref-sub { font-size: 13px; color: var(--muted); margin-bottom: 12px; }
.ref-tags { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; }
.ref-tags span {
  font-size: 11px; padding: 3px 8px; border-radius: 999px;
  background: var(--soft-2); color: var(--accent-d); font-weight: 600;
}
.ref-card-empty { background: var(--soft); border-style: dashed; }
.ref-card-empty .ref-emoji { color: var(--accent-d); }
.ref-link { display: inline-block; margin-top: 8px; font-weight: 700; color: var(--accent-d); }

/* ─── Contact ──────────────────────────────────────────────── */
.contact-grid {
  display: grid; grid-template-columns: 360px 1fr; gap: 48px; align-items: start;
}
.contact-info { display: grid; gap: 22px; }
.contact-block {
  background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.10);
  border-radius: 14px; padding: 18px 20px;
}
.contact-icon { font-size: 22px; margin-bottom: 6px; }
.contact-block h4 { color: #fff; font-size: 14px; margin-bottom: 6px; text-transform: uppercase; letter-spacing: .06em; }
.contact-block p, .contact-block a { color: rgba(220,230,250,.85); font-size: 14px; line-height: 1.55; }
.contact-block a:hover { color: #fff; }

.contact-form {
  background: var(--white); color: var(--text); border-radius: 16px;
  padding: 32px 32px; box-shadow: var(--shadow-lg);
}
.contact-form h3 { color: var(--navy-1); margin-bottom: 18px; font-size: 18px; }
.form-2cols { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.form-row { margin-bottom: 14px; }
.form-row label {
  display: block; font-size: 12px; font-weight: 600; color: #4a5f7a;
  margin-bottom: 6px; letter-spacing: .01em;
}
.form-row input, .form-row select, .form-row textarea {
  width: 100%; padding: 11px 13px; border: 1.5px solid #dde5f0; border-radius: 9px;
  font: inherit; font-size: 14px; color: var(--text); background: #fff;
  transition: border-color .15s, box-shadow .15s;
}
.form-row textarea { resize: vertical; min-height: 100px; }
.form-row input:focus, .form-row select:focus, .form-row textarea:focus {
  outline: none; border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37,99,235,.12);
}
.form-note {
  margin-top: 10px; padding: 10px 12px; border-radius: 8px; font-size: 13px; font-weight: 500;
}
.form-note-ok  { background: #dff3e3; color: #1e7e4d; border: 1px solid #b8e3c6; }
.form-note-err { background: #fde2e2; color: #a02828; border: 1px solid #f5b5b5; }
.form-fineprint { margin-top: 12px; font-size: 11.5px; color: var(--muted); line-height: 1.5; }

/* ─── Footer ───────────────────────────────────────────────── */
.footer {
  background: var(--navy-0); color: #cfd9ef;
  padding: 64px 0 24px;
}
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px;
  padding-bottom: 40px; border-bottom: 1px solid rgba(255,255,255,.08);
}
.footer-brand-col .nav-brand { margin-bottom: 14px; }
.footer-tagline { font-size: 13.5px; color: rgba(207,217,239,.7); line-height: 1.65; max-width: 380px; }
.footer-socials { margin-top: 20px; display: flex; gap: 10px; }
.footer-socials a {
  width: 36px; height: 36px; border-radius: 50%;
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.12);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 700; color: #fff; transition: background .15s, transform .15s;
}
.footer-socials a:hover { background: rgba(255,255,255,.16); transform: translateY(-2px); color: #fff; }

.footer-col h5 {
  color: #fff; font-size: 12px; text-transform: uppercase; letter-spacing: .12em;
  margin-bottom: 14px; font-weight: 700;
}
.footer-col a, .footer-col span {
  display: block; font-size: 13.5px; color: rgba(207,217,239,.75); line-height: 2; cursor: pointer;
}
.footer-col a:hover { color: #fff; }
.footer-bottom {
  padding-top: 22px; display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  font-size: 12.5px; color: rgba(207,217,239,.5);
}
.footer-legal a { color: rgba(207,217,239,.7); }
.footer-legal a:hover { color: #fff; }

/* ─── Back to top button ───────────────────────────────────── */
.back-top {
  position: fixed; bottom: 28px; right: 28px; z-index: 90;
  width: 46px; height: 46px; border-radius: 50%;
  background: var(--accent-d); color: #fff;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 18px; font-weight: 700; box-shadow: 0 8px 22px rgba(29,78,216,.45);
  opacity: 0; pointer-events: none; transform: translateY(8px);
  transition: opacity .2s, transform .2s;
}
.back-top.show { opacity: 1; pointer-events: auto; transform: translateY(0); }
.back-top:hover { background: #1e40af; color: #fff; }

/* ─── Responsive ───────────────────────────────────────────── */
@media (max-width: 1100px) {
  .cards-4         { grid-template-columns: repeat(2, 1fr); }
  .hero-grid       { grid-template-columns: 1fr; }
  .hero-preview    { display: none; }
  .case            { grid-template-columns: 1fr; }
  .case-meta       { border-right: 0; border-bottom: 1px solid var(--rule); }
  .contact-grid    { grid-template-columns: 1fr; }
  .numbers-grid    { grid-template-columns: repeat(3, 1fr); }
  .footer-grid     { grid-template-columns: 1fr 1fr; }
  .nav-links { display: none; }
  .nav-burger { display: flex; }
  .nav-cta { gap: 10px; }
  .nav-links.open {
    display: flex; flex-direction: column; gap: 14px;
    position: absolute; top: 100%; left: 0; right: 0;
    padding: 18px 24px; background: rgba(15,30,64,.96); backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255,255,255,.10);
  }
}
@media (max-width: 720px) {
  .section { padding: 64px 0; }
  .nav { padding: 12px 20px; }
  .nav-brand-name { font-size: 16px; }
  .cards-3, .cards-4, .solutions-grid { grid-template-columns: 1fr; }
  .form-2cols { grid-template-columns: 1fr; }
  .hero-stats { grid-template-columns: repeat(2,1fr); gap: 16px; }
  .numbers-grid { grid-template-columns: repeat(2,1fr); }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .ref-headline { flex-direction: column; text-align: center; gap: 8px; }
  .ref-big { font-size: 48px; }
  .hero-cta .btn { flex: 1 1 100%; }
}