/* BRIGHTLOGIC — one-page site. Tokens first; every colour and type decision derives from these. */
:root{
  --ink:#0F1419;        /* graphite ink: type, dark bands */
  --ink-2:#1A222C;      /* raised surface on ink */
  --paper:#F2F4F6;      /* cool paper: page ground */
  --card:#FFFFFF;
  --line:#D6DCE2;       /* hairlines on paper */
  --line-ink:#2A3440;   /* hairlines on ink */
  --mute:#56616D;       /* secondary text on paper (5.6:1) */
  --mute-ink:#9AA6B2;   /* secondary text on ink (7:1) */
  --trace:#7C8894;      /* diagram traces */
  --signal:#FFC83D;     /* the one bright colour: fills, never text on paper */
  --signal-2:#B38600;   /* signal edge on paper (3.4:1 on white) */
  --display:'Space Grotesk','IBM Plex Sans','Helvetica Neue',Arial,sans-serif;
  --body:'IBM Plex Sans','Helvetica Neue',Arial,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,SFMono-Regular,Menlo,monospace;
  --wrap:1180px;
  --r:10px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:88px;-webkit-text-size-adjust:100%}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{font-family:var(--body);font-size:17px;line-height:1.6;color:var(--ink);background:var(--paper);-webkit-font-smoothing:antialiased;overflow-x:hidden}
img,svg{display:block;max-width:100%}
a{color:inherit}
:focus-visible{outline:3px solid var(--ink);outline-offset:3px;border-radius:4px}
.on-ink :focus-visible{outline-color:var(--signal)}
.skip{position:absolute;left:-999px;top:8px;background:var(--ink);color:#fff;padding:10px 14px;border-radius:6px;z-index:100}
.skip:focus{left:12px}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 28px}
.mono{font-family:var(--mono)}

/* type scale */
h1,h2,h3{font-family:var(--display);font-weight:600;letter-spacing:-.025em;line-height:1.04;color:var(--ink)}
h1{font-size:clamp(40px,5.6vw,74px)}
h2{font-size:clamp(30px,3.8vw,48px)}
h3{font-size:21px;letter-spacing:-.01em;line-height:1.2}
.lede{font-size:clamp(18px,1.6vw,21px);line-height:1.55;color:var(--mute);max-width:56ch}
.eyebrow{font-family:var(--mono);font-size:13px;letter-spacing:.08em;text-transform:uppercase;color:var(--mute);display:flex;align-items:center;gap:10px}
.eyebrow::before{content:"";width:9px;height:9px;background:var(--signal);border-radius:2px;flex:none}
.mark-hl{background:linear-gradient(transparent 58%,var(--signal) 58%,var(--signal) 92%,transparent 92%);padding:0 .06em}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:10px;font-family:var(--body);font-weight:600;font-size:16px;padding:14px 22px;border-radius:var(--r);text-decoration:none;border:1.5px solid var(--ink);transition:transform .15s ease,background .15s ease,color .15s ease;cursor:pointer}
.btn-solid{background:var(--ink);color:#fff}
.btn-solid:hover{background:#000;transform:translateY(-1px)}
.btn-solid .dot{width:10px;height:10px;background:var(--signal);border-radius:2px}
.btn-line{background:transparent;color:var(--ink)}
.btn-line:hover{background:var(--card)}
.on-ink .btn-solid{background:var(--signal);color:var(--ink);border-color:var(--signal)}
.on-ink .btn-solid .dot{background:var(--ink)}

/* header */
.top{position:sticky;top:0;z-index:40;background:rgba(242,244,246,.88);backdrop-filter:saturate(1.4) blur(12px);-webkit-backdrop-filter:saturate(1.4) blur(12px);border-bottom:1px solid transparent;transition:border-color .2s}
.top.scrolled{border-bottom-color:var(--line)}
.top .wrap{height:72px;display:flex;align-items:center;justify-content:space-between;gap:20px}
.brand{display:flex;align-items:center;text-decoration:none;color:var(--ink)}
.brand svg{height:34px;width:auto}
.nav{display:flex;align-items:center;gap:28px}
.nav a{text-decoration:none;font-size:15px;font-weight:500;color:var(--mute)}
.nav a:hover{color:var(--ink)}
.nav .btn{padding:10px 16px;font-size:15px;color:#fff}
.menu-btn{display:none;background:none;border:1.5px solid var(--ink);border-radius:8px;width:44px;height:44px;cursor:pointer;align-items:center;justify-content:center}
.menu-btn span{display:block;width:18px;height:2px;background:var(--ink);position:relative}
.menu-btn span::before,.menu-btn span::after{content:"";position:absolute;left:0;width:18px;height:2px;background:var(--ink)}
.menu-btn span::before{top:-6px}.menu-btn span::after{top:6px}
@media (max-width:860px){
  .menu-btn{display:flex}
  .nav{position:fixed;inset:72px 0 auto 0;background:var(--paper);flex-direction:column;align-items:stretch;gap:0;padding:8px 20px 20px;border-bottom:1px solid var(--line);display:none}
  .nav.open{display:flex}
  .nav a{padding:14px 4px;border-bottom:1px solid var(--line);font-size:17px;color:var(--ink)}
  .nav .btn{margin-top:14px;justify-content:center;border-bottom:1.5px solid var(--ink)}
}

/* hero */
.hero{padding:72px 0 88px}
.hero-grid{display:grid;grid-template-columns:1.12fr .88fr;gap:56px;align-items:center}
.hero h1{margin:22px 0 24px}
.hero .ctas{display:flex;flex-wrap:wrap;gap:12px;margin-top:34px}
.scope-card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:22px 22px 14px;box-shadow:0 30px 60px -40px rgba(15,20,25,.35)}
.scope-head{display:flex;justify-content:space-between;align-items:center;font-family:var(--mono);font-size:12px;color:var(--mute);margin-bottom:10px;gap:12px}
.scope-head .live{display:flex;align-items:center;gap:8px}
.scope-head .live::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--signal);box-shadow:0 0 0 3px rgba(255,200,61,.25)}
.scope{width:100%;height:auto}
.scope-grid{stroke:var(--line);stroke-width:1}
.scope-label{font-family:var(--mono);font-size:12.5px;fill:var(--mute)}
.scope-label-hot{fill:var(--ink);font-weight:600}
.scope-trace{fill:none;stroke:var(--ink);stroke-width:1.8;stroke-linejoin:miter}
.scope-base{stroke:var(--trace);stroke-width:1.2}
.chain .link{stroke:var(--signal-2);stroke-width:1.5;stroke-dasharray:3 4}
.chain .window{fill:var(--signal);stroke:var(--signal-2);stroke-width:1.2}
.scan{stroke:var(--ink);stroke-width:1.2;opacity:0}
.scope-foot{font-size:13px;color:var(--mute);margin-top:8px;border-top:1px solid var(--line);padding-top:10px}
@media (prefers-reduced-motion:no-preference){
  .scan{animation:scan 4.2s cubic-bezier(.4,0,.6,1) .4s 1 both}
  .chain{animation:chain .5s ease-out 1 both}
  .chain.k0{animation-delay:1.5s}.chain.k1{animation-delay:2.65s}.chain.k2{animation-delay:3.8s}
  @keyframes scan{0%{opacity:.55;transform:translateX(0)}92%{opacity:.55}100%{opacity:0;transform:translateX(556px)}}
  @keyframes chain{from{opacity:.12}to{opacity:1}}
}
@media (max-width:980px){.hero-grid{grid-template-columns:1fr;gap:44px}.hero{padding:48px 0 64px}}

/* ink band: the problem */
.band{background:var(--ink);color:#fff;padding:84px 0}
.band h2{color:#fff;max-width:18ch}
.band .lede{color:var(--mute-ink)}
.band-grid{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:end}
.ledger{border-top:1px solid var(--line-ink)}
.ledger div{display:grid;grid-template-columns:1fr auto;gap:16px;padding:14px 0;border-bottom:1px solid var(--line-ink);font-family:var(--mono);font-size:14px;color:var(--mute-ink)}
.ledger b{font-weight:500;color:#fff}
.ledger .truth{color:var(--ink);background:var(--signal);margin:0 -12px;padding:14px 12px;border-radius:6px;border:0}
.ledger .truth b{color:var(--ink)}
.band .fine{font-size:13px;color:var(--mute-ink);margin-top:12px}
@media (max-width:860px){.band-grid{grid-template-columns:1fr;gap:36px}}

/* sections */
.sec{padding:100px 0}
.sec-head{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:end;margin-bottom:52px}
.sec-head h2{margin-top:16px;max-width:20ch}
.sec-head > div:only-child{grid-column:1 / -1}
@media (max-width:860px){.sec-head{grid-template-columns:1fr;gap:18px}.sec{padding:72px 0}}

/* services */
.svc{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:14px;overflow:hidden}
.svc article{background:var(--card);padding:30px 28px 30px;display:flex;flex-direction:column;gap:12px}
.svc .ic{width:40px;height:40px;border-radius:9px;background:var(--paper);display:grid;place-items:center;border:1px solid var(--line)}
.svc .ic svg{width:22px;height:22px}
.svc p{color:var(--mute);font-size:16px}
.svc ul{list-style:none;margin-top:auto;padding-top:8px;display:grid;gap:7px}
.svc li{font-size:15px;display:flex;gap:10px;line-height:1.45}
.svc li::before{content:"";width:6px;height:6px;margin-top:8px;background:var(--signal);border:1px solid var(--signal-2);border-radius:1px;flex:none}
@media (max-width:980px){.svc{grid-template-columns:1fr 1fr}}
@media (max-width:640px){.svc{grid-template-columns:1fr}}

/* pipeline: ad click -> decision */
.pipe{position:relative;display:grid;grid-template-columns:repeat(5,1fr);gap:0;margin-top:8px}
.pipe::before{content:"";position:absolute;left:10%;right:10%;top:23px;height:2px;background:repeating-linear-gradient(90deg,var(--ink) 0 8px,transparent 8px 14px)}
.pipe li{list-style:none;position:relative;text-align:center;padding:0 10px}
.pipe .node{width:48px;height:48px;margin:0 auto 18px;border-radius:50%;border:2px solid var(--ink);background:var(--paper);display:grid;place-items:center;font-family:var(--mono);font-size:13px;font-weight:600;position:relative;z-index:1}
.pipe li:last-child .node{background:var(--signal);border-color:var(--ink)}
.pipe strong{display:block;font-family:var(--display);font-size:18px;font-weight:600;letter-spacing:-.01em}
.pipe span{display:block;font-size:14.5px;color:var(--mute);margin-top:6px;line-height:1.45}
@media (max-width:860px){
  .pipe{grid-template-columns:1fr;gap:26px}
  .pipe::before{left:23px;right:auto;top:10px;bottom:10px;width:2px;height:auto;background:repeating-linear-gradient(180deg,var(--ink) 0 8px,transparent 8px 14px)}
  .pipe li{display:grid;grid-template-columns:48px 1fr;gap:18px;text-align:left;padding:0}
  .pipe .node{margin:0}
}

/* steps + principles + models */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;counter-reset:step}
.steps li{list-style:none;border-top:2px solid var(--ink);padding-top:22px}
.steps .num{font-family:var(--mono);font-size:13px;color:var(--mute);letter-spacing:.06em}
.steps h3{margin:10px 0 10px}
.steps p{color:var(--mute);font-size:16px}
.principles{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.principles div{padding:24px;background:var(--card);border:1px solid var(--line);border-radius:12px}
.principles h3{font-size:18px;margin-bottom:8px}
.principles p{font-size:15px;color:var(--mute)}
.models{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.models div{padding:28px;border:1px solid var(--line);border-radius:12px;background:var(--card);display:flex;flex-direction:column;gap:10px}
.models .tag{font-family:var(--mono);font-size:12.5px;color:var(--mute);text-transform:uppercase;letter-spacing:.08em}
.models p{color:var(--mute);font-size:16px}
.models .fit{margin-top:auto;font-size:14.5px;color:var(--ink);border-top:1px solid var(--line);padding-top:12px}
@media (max-width:980px){.steps,.models{grid-template-columns:1fr}.principles{grid-template-columns:1fr 1fr}}
@media (max-width:560px){.principles{grid-template-columns:1fr}}
.sub-title{margin:72px 0 26px;font-family:var(--display);font-size:26px;font-weight:600;letter-spacing:-.015em}

/* faq */
.faq{max-width:860px;border-top:1px solid var(--line)}
.faq details{border-bottom:1px solid var(--line)}
.faq summary{cursor:pointer;list-style:none;display:flex;justify-content:space-between;gap:20px;padding:22px 0;font-family:var(--display);font-size:19px;font-weight:600;letter-spacing:-.01em}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"";width:12px;height:12px;flex:none;margin-top:8px;border-right:2px solid var(--ink);border-bottom:2px solid var(--ink);transform:rotate(45deg);transition:transform .2s}
.faq details[open] summary::after{transform:rotate(-135deg);margin-top:12px}
.faq details p{padding:0 0 22px;color:var(--mute);max-width:70ch}

/* contact */
.contact{background:var(--ink);color:#fff;padding:96px 0}
.contact h2{color:#fff}
.contact .lede{color:var(--mute-ink)}
.contact-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:64px}
.facts{margin-top:34px;display:grid;gap:0;border-top:1px solid var(--line-ink)}
.facts div{display:grid;grid-template-columns:130px 1fr;gap:12px;padding:14px 0;border-bottom:1px solid var(--line-ink);font-size:15.5px}
.facts dt{font-family:var(--mono);font-size:12.5px;text-transform:uppercase;letter-spacing:.08em;color:var(--mute-ink);padding-top:3px}
.facts a{color:#fff}
form.lead{display:grid;gap:14px;background:var(--ink-2);border:1px solid var(--line-ink);border-radius:14px;padding:28px}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
label.f{display:grid;gap:7px;font-size:14px;color:var(--mute-ink)}
.f input,.f textarea{font:inherit;font-size:16px;color:#fff;background:var(--ink);border:1.5px solid #6B7784;border-radius:8px;padding:12px 14px;width:100%}
.f textarea{min-height:120px;resize:vertical}
.f input:focus-visible,.f textarea:focus-visible{outline:3px solid var(--signal);outline-offset:1px;border-color:var(--signal)}
.f input[aria-invalid="true"],.f textarea[aria-invalid="true"]{border-color:#FF8A7A}
.send{display:flex;align-items:center;gap:18px;flex-wrap:wrap}
.consent{font-size:14px;color:var(--mute-ink);line-height:1.5;max-width:40ch}
.consent a{color:#fff}
.form-msg{font-size:14.5px;min-height:1px}
.form-msg.err{color:#FFB3A8}
.form-ok{display:none;padding:18px;border-radius:10px;background:var(--signal);color:var(--ink);font-weight:500}
.form-ok.show{display:block}
.hp{position:absolute;left:-5000px}
@media (max-width:900px){.contact-grid{grid-template-columns:1fr;gap:40px}.row2{grid-template-columns:1fr}}

/* footer */
.foot{background:var(--ink);color:var(--mute-ink);border-top:1px solid var(--line-ink);padding:34px 0 40px;font-size:14px}
.foot .wrap{display:flex;justify-content:space-between;gap:20px 40px;flex-wrap:wrap;align-items:center}
.foot-id{display:flex;align-items:center;gap:22px;flex-wrap:wrap}
.foot a{color:var(--mute-ink)}
.foot .brand{color:#fff}

/* legal page */
.legal{max-width:760px;padding:64px 0 96px}
.legal h1{font-size:clamp(34px,4.5vw,52px);margin-bottom:12px}
.legal h2{font-size:24px;margin:40px 0 10px}
.legal p,.legal li{color:#2B333C;margin-bottom:12px}
.legal ul{padding-left:20px}

/* classes that replaced inline styles */
.hero-micro{font-size:13px;color:var(--mute);margin-top:28px}
.on-ink .eyebrow{color:var(--mute-ink)}
.band h2{margin:16px 0 22px}
.contact h2{margin:16px 0 20px}
.sec-tight{padding-top:20px}
.sec-card{background:var(--card);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.opt{opacity:.75}
.back{margin-top:28px}