/* =========================================================
   VOLTLINK — Design System
   Style: Trust & Authority + signature "circuit / câblage"
   ========================================================= */

:root {
  /* Couleurs */
  --ink:          #0A1124;   /* encre marine profonde */
  --ink-2:        #0E1830;
  --ink-3:        #14203C;
  --bg:           #FFFFFF;
  --bg-soft:      #F5F7FB;
  --text:         #0E1830;
  --text-muted:   #51607A;
  --text-on-dark: #E7ECF6;
  --muted-on-dark:#9AA8C2;

  --accent:       #1463E6;   /* bleu électrique — "volt" */
  --accent-strong:#0B4FB8;
  --accent-soft:  #E8F0FE;
  --copper:       #C8763C;   /* signature — le conducteur */

  --border:       #E3E8F2;
  --border-dark:  rgba(255,255,255,.10);
  --ring:         rgba(20,99,230,.40);

  /* Typo */
  --font-display: "Space Grotesk", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono:    "JetBrains Mono", ui-monospace, SFMono-Regular, monospace;

  /* Rythme */
  --radius:       16px;
  --radius-sm:    10px;
  --shadow-sm:    0 1px 2px rgba(10,17,36,.06), 0 1px 3px rgba(10,17,36,.05);
  --shadow-md:    0 10px 30px -12px rgba(10,17,36,.18);
  --shadow-lg:    0 30px 60px -25px rgba(10,17,36,.30);
  --container:    1160px;
  --ease:         cubic-bezier(.16,1,.3,1);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3 { font-family: var(--font-display); font-weight: 600; line-height: 1.1; margin: 0; letter-spacing: -.02em; }

/* ---------- Accessibilité ---------- */
.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 200;
  background: var(--accent); color: #fff; padding: 10px 16px; border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus { left: 0; }
:focus-visible { outline: 3px solid var(--ring); outline-offset: 3px; border-radius: 4px; }

/* ---------- Layout ---------- */
.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 24px; }
.section { padding: 104px 0; }
.section-soft { background: var(--bg-soft); }
.section-dark { background: var(--ink); color: var(--text-on-dark); }

.section-head { max-width: 720px; margin: 0 auto 56px; text-align: center; }
.section-title { font-size: clamp(1.7rem, 3.4vw, 2.5rem); }
.section-sub { color: var(--text-muted); font-size: 1.08rem; margin: 18px 0 0; }
.section-sub-dark { color: var(--muted-on-dark); }

/* ---------- Eyebrow (étiquette mono) ---------- */
.eyebrow {
  font-family: var(--font-mono); font-size: .78rem; font-weight: 500;
  letter-spacing: .14em; text-transform: uppercase;
  color: var(--accent); margin: 0 0 16px;
  display: inline-flex; align-items: center; gap: 10px;
}
.eyebrow::before { content: ""; width: 26px; height: 2px; background: var(--copper); display: inline-block; }
.eyebrow-dark { color: var(--accent-strong); }

/* ---------- Boutons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  font-family: var(--font-body); font-weight: 600; font-size: .98rem;
  padding: 14px 26px; border-radius: 999px; border: 1.5px solid transparent;
  cursor: pointer; transition: transform .2s var(--ease), background .2s var(--ease), box-shadow .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease);
  white-space: nowrap;
}
.btn-sm { padding: 10px 20px; font-size: .92rem; }
.btn-block { width: 100%; }
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 8px 20px -8px var(--ring); }
.btn-primary:hover { background: var(--accent-strong); transform: translateY(-2px); box-shadow: 0 14px 28px -10px var(--ring); }
.btn-ghost { background: transparent; color: var(--text-on-dark); border-color: var(--border-dark); }
.hero .btn-ghost { color: var(--text-on-dark); border-color: rgba(255,255,255,.22); }
.btn-ghost:hover { border-color: var(--accent); color: #fff; transform: translateY(-2px); }
.btn-ghost svg { transition: transform .25s var(--ease); }
.btn-ghost:hover svg { transform: translateX(4px); }

/* ============ HEADER ============ */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.72); backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid transparent; transition: border-color .3s, box-shadow .3s, background .3s;
}
.site-header.scrolled { border-bottom-color: var(--border); box-shadow: var(--shadow-sm); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }

.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); }
.brand-mark { color: var(--accent); display: inline-flex; }
.brand-name { font-family: var(--font-display); font-weight: 700; font-size: 1.22rem; letter-spacing: .02em; }
.brand-name-accent { color: var(--accent); }

.nav { display: flex; align-items: center; gap: 30px; }
.nav > a:not(.btn) { font-weight: 500; font-size: .98rem; color: var(--text); position: relative; padding: 4px 0; transition: color .2s; }
.nav > a:not(.btn)::after { content: ""; position: absolute; left: 0; bottom: -2px; width: 0; height: 2px; background: var(--accent); transition: width .25s var(--ease); }
.nav > a:not(.btn):hover { color: var(--accent); }
.nav > a:not(.btn):hover::after { width: 100%; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--ink); border-radius: 2px; transition: transform .25s, opacity .25s; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-nav { display: none; flex-direction: column; gap: 6px; padding: 16px 24px 24px; border-bottom: 1px solid var(--border); background: #fff; }
.mobile-nav a:not(.btn) { padding: 12px 4px; font-weight: 500; border-bottom: 1px solid var(--border); }
.mobile-nav .btn { margin-top: 12px; }

/* ============ HERO ============ */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(1100px 520px at 78% -10%, rgba(20,99,230,.22), transparent 60%),
    radial-gradient(800px 500px at 8% 110%, rgba(200,118,60,.12), transparent 55%),
    linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  color: var(--text-on-dark);
  padding: clamp(96px, 14vw, 168px) 0 clamp(80px, 10vw, 128px);
}
.circuit { position: absolute; inset: 0; opacity: .5; pointer-events: none; }
.circuit svg { width: 100%; height: 100%; }
.circuit-traces path { stroke: rgba(255,255,255,.13); }
.circuit-nodes circle { fill: rgba(255,255,255,.45); }
.circuit-nodes .node-copper { fill: var(--copper); }
.pulse { stroke: var(--accent); stroke-dasharray: 90 1200; opacity: .9; filter: drop-shadow(0 0 6px rgba(20,99,230,.8)); }
.pulse-1 { animation: dash 7s linear infinite; }
.pulse-2 { stroke: var(--copper); filter: drop-shadow(0 0 6px rgba(200,118,60,.7)); animation: dash 9s linear infinite 1.5s; }
.pulse-3 { animation: dash 11s linear infinite 3s; }
@keyframes dash { from { stroke-dashoffset: 1290; } to { stroke-dashoffset: 0; } }

.hero-inner { position: relative; z-index: 2; max-width: 880px; }
.hero .eyebrow { color: #8FB6FF; }
.hero-title { font-size: clamp(2.05rem, 6vw, 4rem); font-weight: 700; letter-spacing: -.03em; overflow-wrap: break-word; }
.hero-title .grad {
  background: linear-gradient(100deg, #4D8DFF 0%, #8FB6FF 55%, var(--copper) 130%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-lead { font-size: clamp(1.05rem, 2vw, 1.28rem); color: var(--muted-on-dark); max-width: 660px; margin: 26px 0 0; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 38px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 44px; }
.hero-tags li {
  font-family: var(--font-mono); font-size: .82rem; color: var(--text-on-dark);
  padding: 7px 15px; border: 1px solid var(--border-dark); border-radius: 999px;
  background: rgba(255,255,255,.04);
}

/* ============ BANDEAU ============ */
.strip { background: var(--ink-2); color: var(--text-on-dark); border-top: 1px solid var(--border-dark); }
.strip-inner { padding: 40px 24px; }
.strip-text { margin: 0; max-width: 980px; font-size: 1.12rem; color: var(--muted-on-dark); }
.strip-text strong { color: var(--text-on-dark); font-weight: 600; }

/* ============ CARTES EXPERTISES ============ */
.cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.card {
  position: relative; background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius); padding: 34px 32px;
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
}
.card::before {
  content: ""; position: absolute; left: 0; top: 24px; bottom: 24px; width: 3px;
  background: linear-gradient(var(--accent), var(--copper)); border-radius: 0 3px 3px 0;
  transform: scaleY(0); transform-origin: top; transition: transform .35s var(--ease);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: #d4ddee; }
.card:hover::before { transform: scaleY(1); }
.card-icon {
  width: 56px; height: 56px; border-radius: 14px; display: grid; place-items: center;
  background: var(--accent-soft); color: var(--accent); margin-bottom: 22px;
}
.card-title { font-size: 1.28rem; margin-bottom: 12px; }
.card-text { color: var(--text-muted); margin: 0 0 18px; }
.card-list { display: flex; flex-direction: column; gap: 9px; }
.card-list li { position: relative; padding-left: 24px; font-size: .96rem; color: var(--text); }
.card-list li::before {
  content: ""; position: absolute; left: 0; top: .55em; width: 9px; height: 9px;
  border: 2px solid var(--accent); border-radius: 50%;
}

/* ============ APPROCHE / STEPS ============ */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: step; }
.step {
  position: relative; padding: 30px 26px; border: 1px solid var(--border-dark);
  border-radius: var(--radius); background: rgba(255,255,255,.03);
  transition: background .3s, border-color .3s, transform .3s var(--ease);
}
.step:hover { background: rgba(255,255,255,.06); border-color: rgba(255,255,255,.18); transform: translateY(-4px); }
.step-num { font-family: var(--font-mono); font-size: 1.05rem; color: var(--copper); display: block; margin-bottom: 14px; }
.step-title { font-size: 1.22rem; color: #fff; margin-bottom: 8px; }
.step-text { color: var(--muted-on-dark); font-size: .96rem; margin: 0; }

/* ============ SECTEURS ============ */
.secteurs-grid { display: grid; grid-template-columns: 1fr 1.15fr; gap: 56px; align-items: center; }
.secteurs-intro .btn { margin-top: 26px; }
.secteurs-list { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.secteur { padding: 26px 24px; border: 1px solid var(--border); border-radius: var(--radius); background: #fff; transition: border-color .3s, box-shadow .3s, transform .3s var(--ease); }
.secteur:hover { border-color: #d4ddee; box-shadow: var(--shadow-sm); transform: translateY(-3px); }
.secteur h3 { font-size: 1.12rem; margin-bottom: 8px; color: var(--ink); }
.secteur p { margin: 0; color: var(--text-muted); font-size: .95rem; }

/* ============ À PROPOS ============ */
.apropos-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: start; }
.apropos-text .section-sub { margin-top: 18px; }
.values { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.value { padding: 26px 24px; border-radius: var(--radius); background: #fff; border: 1px solid var(--border); transition: transform .3s var(--ease), box-shadow .3s; }
.value:hover { transform: translateY(-3px); box-shadow: var(--shadow-sm); }
.value h3 { font-size: 1.08rem; margin-bottom: 8px; color: var(--accent-strong); }
.value p { margin: 0; color: var(--text-muted); font-size: .95rem; }

/* ============ CONTACT ============ */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.contact-info { margin-top: 34px; display: flex; flex-direction: column; gap: 20px; }
.contact-info li { display: flex; flex-direction: column; gap: 3px; }
.contact-label { font-family: var(--font-mono); font-size: .74rem; letter-spacing: .12em; text-transform: uppercase; color: var(--copper); }
.contact-info a, .contact-info span:not(.contact-label) { font-size: 1.08rem; color: var(--text-on-dark); transition: color .2s; }
.contact-info a:hover { color: #8FB6FF; }

.contact-form { background: rgba(255,255,255,.04); border: 1px solid var(--border-dark); border-radius: var(--radius); padding: 32px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: .9rem; font-weight: 500; margin-bottom: 7px; color: var(--text-on-dark); }
.field input, .field textarea {
  width: 100%; padding: 13px 15px; border-radius: var(--radius-sm); font: inherit; font-size: .98rem;
  background: rgba(255,255,255,.05); border: 1.5px solid var(--border-dark); color: #fff;
  transition: border-color .2s, background .2s;
}
.field input::placeholder, .field textarea::placeholder { color: var(--muted-on-dark); }
.field input:focus, .field textarea:focus { outline: none; border-color: var(--accent); background: rgba(255,255,255,.08); }
.field textarea { resize: vertical; min-height: 110px; }
.form-note { font-size: .82rem; color: var(--muted-on-dark); margin: 14px 0 0; }
.hp-field { position: absolute; left: -9999px; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.form-status { margin: 14px 0 0; font-size: .92rem; padding: 12px 15px; border-radius: var(--radius-sm); }
.form-status.is-success { background: rgba(34,197,94,.12); color: #86efac; border: 1px solid rgba(34,197,94,.35); }
.form-status.is-error { background: rgba(248,113,113,.12); color: #fca5a5; border: 1px solid rgba(248,113,113,.35); }

/* ============ FOOTER ============ */
.site-footer { background: #060B17; color: var(--muted-on-dark); padding: 64px 0 28px; }
.footer-inner { display: flex; justify-content: space-between; gap: 40px; flex-wrap: wrap; padding-bottom: 36px; border-bottom: 1px solid var(--border-dark); }
.footer-brand { max-width: 420px; }
.footer-brand .brand-name { color: #fff; font-size: 1.4rem; }
.footer-brand p { margin: 14px 0 0; font-size: .95rem; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 22px; align-content: start; }
.footer-nav a { font-size: .96rem; transition: color .2s; }
.footer-nav a:hover { color: #fff; }
.footer-legal { padding-top: 24px; }
.footer-legal p { margin: 0 0 4px; font-size: .84rem; color: var(--muted-on-dark); }
.footer-bottom { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 20px; margin-top: 16px; border-top: 1px solid var(--border-dark); font-size: .86rem; }
.footer-tag { font-family: var(--font-mono); color: var(--copper); }

/* ============ PAGE LÉGALE ============ */
.page-hero {
  background:
    radial-gradient(800px 360px at 80% -20%, rgba(20,99,230,.22), transparent 60%),
    linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  color: var(--text-on-dark);
  padding: 72px 0 60px;
}
.page-hero h1 { font-size: clamp(2rem, 5vw, 3rem); }
.page-hero .eyebrow { color: #8FB6FF; }
.page-hero-sub { color: var(--muted-on-dark); font-family: var(--font-mono); font-size: .85rem; margin: 14px 0 0; }

.legal { padding: 72px 0 96px; }
.legal-inner { max-width: 820px; }
.legal-block { margin-bottom: 44px; }
.legal-block h2 { font-size: 1.32rem; color: var(--ink); margin-bottom: 14px; }
.legal-block p { color: var(--text-muted); margin: 0 0 14px; }
.legal-block a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
.legal-block a:hover { color: var(--accent-strong); }
.legal-list { display: flex; flex-direction: column; gap: 8px; margin: 0 0 14px; }
.legal-list li { position: relative; padding-left: 20px; color: var(--text); }
.legal-list li::before { content: ""; position: absolute; left: 0; top: .65em; width: 7px; height: 7px; border: 2px solid var(--accent); border-radius: 50%; }
.legal-block em { color: var(--copper); font-style: normal; background: rgba(200,118,60,.08); padding: 1px 6px; border-radius: 4px; }
.legal-back { margin-top: 48px; padding-top: 28px; border-top: 1px solid var(--border); }
.legal-back a { font-weight: 600; color: var(--accent); }

/* ============ Reveal animation ============ */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

/* ============ RESPONSIVE ============ */
@media (max-width: 1024px) {
  .section { padding: 84px 0; }
  .secteurs-grid, .apropos-grid, .contact-grid { grid-template-columns: 1fr; gap: 40px; }
  .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  body { font-size: 16px; }
  .nav { display: none; }
  .nav-toggle { display: flex; }
  .mobile-nav { display: none; }
  .mobile-nav.open { display: flex; }
  .cards { grid-template-columns: 1fr; }
  .secteurs-list, .values { grid-template-columns: 1fr; }
  .section { padding: 72px 0; }
  .hero-cta .btn { flex: 1 1 auto; }
}
@media (max-width: 480px) {
  .container { padding: 0 18px; }
  .card, .contact-form { padding: 26px 22px; }
  .footer-bottom { flex-direction: column; gap: 8px; }
}

/* ============ Reduced motion ============ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; }
  .pulse { display: none; }
}