:root{
  /* Night sky + paper. See research/19-astrelyn-brand-theme.md */
  --paper:#f6f5f1; --card:#fffefb; --sunken:#ecebe4;
  --ink:#161a20; --ink-2:#3d4452; --muted:#5b6270;
  --line:#dcd9cf; --line-2:#c9c5b9; --control:#7f838a;
  --navy:#1b3358; --navy-2:#24457a; --navy-soft:#e6ebf4;
  --brass:#7a5d17; --star-tint:#f8f0d9; --starlight:#e8cf8f; --star-dim:#6e6247;
  --midnight:#0e1a33; --surface-1:#15233f; --surface-2:#1d2f52; --line-dark:#2a3a58; --muted-dark:#9aa3b5;
  --ok:#1f7a4d;
  --serif:"Instrument Serif","Iowan Old Style","Palatino Linotype",Georgia,serif;
  --sans:"Instrument Sans","Helvetica Neue",Arial,system-ui,sans-serif;
  --mono:ui-monospace,"SF Mono",Menlo,monospace;
  --ease:cubic-bezier(.2,.7,.2,1); --dur:.18s;
  /* paper grain: a faint noise tile over the flat colour, no gradients */
  --grain:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .075 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  --grain-light:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 .07 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;font-size:clamp(16px,11px + .4vw,22px)}
body{margin:0;font-family:var(--sans);color:var(--ink);background:var(--grain),var(--paper);line-height:1.6;font-size:1.0625rem;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
svg{display:block}
a{color:var(--navy);text-decoration:none;transition:color var(--dur) var(--ease)}
a:hover{text-decoration:underline;text-underline-offset:.15em;text-decoration-thickness:1px}
::selection{background:var(--star-tint);color:var(--ink)}
:focus-visible{outline:2px solid var(--navy);outline-offset:3px}
h1,h2{margin:0 0 .45em;font-family:var(--serif);font-weight:400;line-height:1.04;letter-spacing:-.012em;text-wrap:balance}
h1{font-size:clamp(2.75rem,5.6vw,4.5rem)}
h1 em,h2 em{font-style:italic;color:var(--brass)}
h2{font-size:clamp(2.1rem,3.6vw,3.1rem);max-width:22ch}
h3{margin:0 0 .4em;font-family:var(--serif);font-weight:400;font-size:1.6rem;line-height:1.1;letter-spacing:-.006em}
p{margin:0 0 1em;text-wrap:pretty}
.container{width:min(70rem,100% - 3rem);margin-inline:auto}
.narrow{max-width:42rem}
.skip{position:absolute;left:-999px;top:0;background:var(--ink);color:#fff;padding:.5rem .75rem}
.skip:focus{left:.5rem;z-index:100}
.lead{font-size:1.2rem;color:var(--ink-2);max-width:52ch;line-height:1.55}
.star{display:inline-block;width:.6em;height:.6em;background:currentColor;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 1.5c.9 5.6 4.9 9.6 10.5 10.5C16.9 12.9 12.9 16.9 12 22.5 11.1 16.9 7.1 12.9 1.5 12 7.1 11.1 11.1 7.1 12 1.5z'/%3E%3C/svg%3E") center/contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 1.5c.9 5.6 4.9 9.6 10.5 10.5C16.9 12.9 12.9 16.9 12 22.5 11.1 16.9 7.1 12.9 1.5 12 7.1 11.1 11.1 7.1 12 1.5z'/%3E%3C/svg%3E") center/contain no-repeat;color:var(--brass)}
.star.dim{color:var(--line-2)}

/* labels: eyebrows and numerals carry the rhythm instead of icons */
.eyebrow{display:flex;align-items:center;gap:.55rem;margin:0 0 1.25rem;font-size:.74rem;font-weight:600;letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.eyebrow .star{width:.8em;height:.8em;color:var(--brass)}
.section-head{margin-bottom:3.25rem}
.work-list .num{font-family:var(--mono);font-size:.74rem;letter-spacing:.1em;color:var(--muted);margin:0 0 .65rem}

/* header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(246,245,241,.84);backdrop-filter:saturate(160%) blur(14px);-webkit-backdrop-filter:saturate(160%) blur(14px);border-bottom:1px solid rgba(22,26,32,.09)}
.nav-row{display:flex;align-items:center;justify-content:space-between;height:4.5rem;gap:1rem}
.brand{display:flex;align-items:flex-end;gap:0;color:var(--ink);font-family:var(--serif);font-size:1.6rem;line-height:1;letter-spacing:0}
.brand:hover{text-decoration:none}
.brand-logo{height:2.4rem;width:auto;display:block}
.nav{display:flex;align-items:center;gap:2rem}
.nav a{position:relative;color:var(--ink-2);font-weight:500;font-size:.92rem;letter-spacing:.005em}
.nav a:hover{color:var(--ink);text-decoration:none}
.nav a:not(.btn)::after{content:"";position:absolute;left:0;right:0;bottom:-.4rem;height:1px;background:currentColor;transform:scaleX(0);transform-origin:left;transition:transform .25s var(--ease)}
.nav a:not(.btn):hover::after{transform:scaleX(1)}
.nav-toggle{display:none;background:none;border:0;padding:.5rem;cursor:pointer}
.nav-toggle span{display:block;width:1.375rem;height:1.5px;background:var(--ink);margin:.375rem 0;transition:transform .2s,opacity .2s}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;padding:.9rem 1.55rem;border-radius:.5rem;font-weight:600;font-size:.98rem;letter-spacing:.005em;border:1px solid transparent;cursor:pointer;font-family:inherit;transition:background var(--dur) var(--ease),border-color var(--dur) var(--ease),color var(--dur) var(--ease),transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease)}
.btn:hover{text-decoration:none}
.btn:active{transform:translateY(0)!important}
.btn-primary{background:var(--navy);color:#fff;box-shadow:inset 0 1px 0 rgba(255,255,255,.1),0 .5rem 1rem -.6rem rgba(27,51,88,.55)}
.btn-primary:hover{background:var(--navy-2);transform:translateY(-1px);box-shadow:inset 0 1px 0 rgba(255,255,255,.1),0 .8rem 1.25rem -.6rem rgba(27,51,88,.6)}
.btn-ghost{background:transparent;color:var(--ink);border-color:var(--line-2)}
.btn-ghost:hover{border-color:var(--ink);background:var(--card);transform:translateY(-1px)}
.btn-sm{padding:.5625rem 1rem;font-size:.88rem}
.nav .btn-sm{color:#fff}

/* hero */
.hero{padding:5.5rem 0 5rem;border-bottom:1px solid var(--line)}
.hero-grid{display:grid;grid-template-columns:1fr 1fr;gap:5rem;align-items:center}
.hero-copy .lead{margin-bottom:1.8em}
.cta-row{display:flex;flex-wrap:wrap;gap:.75rem;margin-bottom:2.4rem}
.facts{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:.6rem 0;font-size:.9rem;color:var(--ink-2)}
.facts li{padding:0 1.25rem;border-left:1px solid var(--line-2);line-height:1.2}
.facts li:first-child{padding-left:0;border-left:0}
/* page enter: the only motion besides the chat */
.hero-copy,.hero-demo{animation:rise .5s var(--ease) both}
.hero-demo{animation-delay:.12s}
@keyframes rise{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* the demo, framed as a browser surface */
.hero-demo{background:var(--card);border:1px solid var(--line);border-radius:1rem;box-shadow:0 .25rem .75rem -.5rem rgba(14,26,51,.2),0 2.5rem 4rem -2.5rem rgba(14,26,51,.45);overflow:hidden}
.demo-bar{display:flex;align-items:center;gap:.4rem;padding:.65rem .9rem;border-bottom:1px solid var(--line);background:var(--paper)}
.demo-bar span{width:.55rem;height:.55rem;border-radius:50%;border:1px solid var(--line-2)}
.demo-bar em{margin-left:.75rem;flex:1;max-width:20rem;text-align:center;font-style:normal;color:var(--muted);font-size:.72rem;font-family:var(--mono);background:var(--card);border:1px solid var(--line);border-radius:999px;padding:.22rem .8rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.demo-screen{height:clamp(26rem,100vh - 13rem,33rem);position:relative}
.demo-screen iframe{width:100%;height:100%;border:0;display:block}
.demo-caption{font-size:.82rem;color:var(--muted);margin:.75rem .25rem 0}
/* static fallback that mirrors the live intake */
.mock{padding:1rem 1.125rem;display:flex;flex-direction:column;height:100%;font-size:.85rem}
.mock-head{display:flex;align-items:center;gap:.4rem;font-weight:600;color:var(--ink);font-size:.78rem;margin-bottom:.75rem}
.mock-head span{color:var(--muted);font-weight:400}
.mock-path{margin-left:auto;display:flex;align-items:center;gap:.25rem}
.mock-path u{display:block;width:.375rem;height:.375rem;border-radius:999px;background:var(--line-2);transition:width .25s var(--ease),background var(--dur) var(--ease)}
.mock-path u.on{width:1rem;background:var(--ink)}
.mock-thread{flex:1;min-height:0;background:var(--paper);border:1px solid var(--line);border-radius:.875rem;padding:1rem;display:flex;flex-direction:column;gap:.6rem;overflow-y:auto;overscroll-behavior:contain;scrollbar-width:thin}
.mock-row{display:flex;align-items:flex-end;gap:.5rem}
.mock-msg{background:var(--card);color:var(--ink);padding:.625rem .875rem;border-radius:.875rem;border-bottom-left-radius:.25rem;border:1px solid var(--line);max-width:80%;line-height:1.45;box-shadow:0 1px 2px rgba(14,26,51,.04)}
.mock-row.me{justify-content:flex-end}
.mock-row.me .mock-msg{background:var(--navy);color:#fff;border-color:var(--navy);border-radius:.875rem;border-bottom-right-radius:.25rem}
.mock-input{margin-top:.75rem;display:flex;align-items:center;gap:.5rem}
.mock-input input{flex:1;min-width:0;border:1px solid var(--control);border-radius:.75rem;padding:.75rem .875rem;font:inherit;font-size:max(16px,.85rem);color:var(--ink);background:var(--card);transition:border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease)}
.mock-input input::placeholder{color:var(--muted)}
.mock-input input:focus{outline:2px solid var(--navy);outline-offset:1px;border-color:var(--navy)}
.mock-input input:disabled{background:var(--paper)}
.mock-input button{flex:none;width:3rem;height:3rem;border:0;border-radius:.75rem;background:var(--navy);color:#fff;font:inherit;font-size:1.05rem;cursor:pointer;transition:background var(--dur) var(--ease),transform var(--dur) var(--ease)}
.mock-input button:hover{background:var(--navy-2)}
.mock-input button:active{transform:scale(.96)}
.mock-input button:disabled{opacity:.45;cursor:default;transform:none}
.mock-foot{margin:.55rem 0 0;font-size:.7rem;color:var(--muted)}
.chat-tools{display:flex;justify-content:space-between;gap:.5rem;margin-top:.5rem}
.chat-tools[hidden]{display:none}
.tool{display:inline-flex;align-items:center;gap:.35rem;border:1px solid var(--line-2);background:var(--card);color:var(--ink-2);border-radius:999px;padding:.4rem .8rem;font:inherit;font-size:.78rem;font-weight:500;cursor:pointer;line-height:1.2;transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease),color var(--dur) var(--ease)}
.tool span{font-size:.95em}
.tool:hover{border-color:var(--navy);color:var(--ink);background:var(--navy-soft)}
.tool[hidden]{display:none}
.tool#chatReset{margin-left:auto}
.chat-chips{display:flex;flex-wrap:wrap;gap:.4rem;padding-left:1.1rem;margin-top:auto;padding-top:.5rem}
.chip{border:1px solid var(--line-2);background:var(--card);color:var(--ink);border-radius:999px;padding:.42rem .8rem;font:inherit;font-size:.82rem;cursor:pointer;line-height:1.2;transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease),transform var(--dur) var(--ease)}
.chip:hover{border-color:var(--navy);background:var(--navy-soft);transform:translateY(-1px)}
.mock-msg p{margin:0 0 .5rem}
.mock-msg .btn{margin-top:.15rem}
.mock-msg.typing{display:flex;gap:.25rem;padding:.8rem .9rem}
.mock-msg.typing i{width:.35rem;height:.35rem;border-radius:50%;background:var(--muted);animation:dot 1s infinite ease-in-out}
.mock-msg.typing i:nth-child(2){animation-delay:.15s}
.mock-msg.typing i:nth-child(3){animation-delay:.3s}
@keyframes dot{0%,80%,100%{opacity:.25}40%{opacity:1}}
.mock[hidden],.booking[hidden]{display:none}
.booking{position:absolute;inset:0;display:flex;flex-direction:column;background:var(--card)}
.booking-bar{display:flex;justify-content:space-between;align-items:center;gap:1rem;padding:.6rem .875rem;border-bottom:1px solid var(--line);font-size:.8rem}
.booking-bar button{background:none;border:0;padding:0;font:inherit;color:var(--navy);cursor:pointer}
.booking iframe{flex:1;width:100%;border:0;display:block}

/* proof: one cited number, set like a pull quote */
.proof{padding:3rem 0;border-bottom:1px solid var(--line);background:var(--grain),var(--card)}
.proof-grid{display:grid;grid-template-columns:auto 1fr;gap:3rem;align-items:center;max-width:66rem}
.proof .proof-num{margin:0;max-width:none;font-family:var(--serif);font-size:clamp(3.6rem,6vw,5.2rem);line-height:.85;letter-spacing:-.02em;color:var(--ink);padding-right:3rem;border-right:1px solid var(--line)}
.proof-num small{display:block;font-family:var(--sans);font-size:.68rem;font-weight:600;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin-top:.7rem;line-height:1.3}
.proof p{margin:0;max-width:60ch;color:var(--ink-2);font-size:1.05rem;line-height:1.6}
.proof strong{color:var(--ink);font-weight:600}
.proof .cite{display:block;margin-top:.5rem;color:var(--muted);font-size:.84em}

/* sections */
.section{padding:7.5rem 0}
.section-dark{background:var(--grain-light),var(--midnight);color:var(--paper)}
.section-dark h2{color:#fff}
.section-dark .star{color:var(--starlight)}
.section-dark .eyebrow{color:var(--muted-dark)}
.section-dark .eyebrow .star{color:var(--starlight)}
.section-dark p{color:var(--muted-dark)}
.section-dark h3{color:#fff}

/* work: three columns on a hairline grid */
.work-list{display:grid;grid-template-columns:repeat(3,1fr);gap:0}
.work-list article{padding:0 2.5rem;display:grid;grid-template-rows:subgrid;grid-row:span 4;align-content:start}
.work-list article:first-child{padding-left:0}
.work-list article:last-child{padding-right:0}
.work-list article+article{border-left:1px solid var(--line)}
.work-list p{color:var(--ink-2);font-size:.98rem;margin:0}
.work-list h3{margin-bottom:.5rem}
.surface{background:var(--card);border:1px solid var(--line);border-radius:.875rem;padding:1.125rem;margin-bottom:1.75rem;font-size:.8rem;min-height:12.5rem;display:flex;flex-direction:column;gap:.75rem;justify-content:center;box-shadow:0 1px 2px rgba(14,26,51,.04),0 1.25rem 2rem -1.5rem rgba(14,26,51,.25);transition:transform .35s var(--ease),box-shadow .35s var(--ease)}
.work-list article:hover .surface{transform:translateY(-3px);box-shadow:0 1px 2px rgba(14,26,51,.04),0 1.75rem 2.5rem -1.5rem rgba(14,26,51,.32)}
.s-row{display:flex;align-items:center;gap:.625rem}
.s-row span{display:flex;flex-direction:column;min-width:0;flex:1}
.s-row small{color:var(--muted);font-size:.72rem}
.s-ring{width:2rem;height:2rem;border-radius:50%;border:3px solid var(--ok);display:grid;place-items:center;font-size:.7rem;font-weight:600;font-family:var(--sans);font-style:normal}
.s-badge{font-style:normal;font-size:.7rem;font-weight:600;color:var(--brass);background:var(--star-tint);padding:.2rem .5rem;border-radius:999px;white-space:nowrap}
.s-card{border:1px solid var(--line);border-radius:.6rem;padding:.75rem;line-height:1.4;color:var(--ink-2);display:flex;flex-direction:column;align-items:flex-start;background:var(--paper)}
.s-card small{display:block;color:var(--muted);text-transform:uppercase;letter-spacing:.1em;font-size:.62rem;font-weight:600;margin-bottom:.35rem}
.s-btn{display:inline-block;width:max-content;margin-top:.75rem;background:var(--navy);color:#fff;font-weight:600;padding:.4rem .7rem;border-radius:.4rem;font-size:.72rem}
.s-log{list-style:none;margin:0;padding:0;display:grid;gap:.55rem;color:var(--ink-2)}
.s-log li{display:flex;align-items:center;gap:.5rem}
.s-log i{width:.5rem;height:.5rem;border-radius:50%;background:var(--ok);flex:none}
.s-log i.wait{background:var(--starlight);border:1px solid var(--brass)}
.s-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:.5rem}
.s-stats div{display:flex;flex-direction:column-reverse;justify-content:flex-end}
.s-stats small{display:block;color:var(--muted);font-size:.66rem;line-height:1.3;margin-top:.2rem}
.s-stats b{font-family:var(--serif);font-weight:400;font-size:1.3rem;color:var(--ink);font-variant-numeric:tabular-nums}
.s-bars{display:flex;align-items:flex-end;gap:.35rem;height:3.25rem}
.s-bars i{flex:1;background:var(--navy);border-radius:.15rem .15rem 0 0;opacity:.85}

/* process: the constellation */
.constellation{width:100%;max-width:60rem;height:auto;margin:.5rem 0 1.5rem}
.constellation line{stroke:var(--star-dim);stroke-width:1}
.constellation circle{fill:var(--starlight)}
.constellation .s{fill:var(--starlight)}
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:0;margin-top:1.5rem}
.steps article{padding:0 2.5rem}
.steps article:first-child{padding-left:0}
.steps article:last-child{padding-right:0}
.steps article+article{border-left:1px solid var(--line-dark)}
.steps .step-num{font-family:var(--serif);font-size:2.6rem;line-height:1;letter-spacing:-.02em;color:var(--star-dim);margin:0 0 1.25rem}
.step-when{font-size:.74rem;font-weight:600;color:var(--muted-dark);margin-bottom:.75rem;letter-spacing:.12em;text-transform:uppercase}
.steps h3{font-size:1.7rem}
.steps p{font-size:.98rem}

/* about */
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:5rem;align-items:start}
.principles{list-style:none;margin:.5rem 0 0;padding:0;counter-reset:p}
.principles li{counter-increment:p;position:relative;padding:1.125rem 0 1.125rem 2.75rem;border-top:1px solid var(--line);color:var(--ink-2);font-size:.98rem}
.principles li::before{content:counter(p,decimal-leading-zero);position:absolute;left:0;top:calc(1.125rem + .3em);font-family:var(--mono);font-size:.74rem;letter-spacing:.1em;color:var(--brass);line-height:1}
.principles li:last-child{border-bottom:1px solid var(--line)}
.principles strong{color:var(--ink);font-weight:600}

/* book */
.book{background:var(--grain),var(--card);border-top:1px solid var(--line);text-align:center;padding:8rem 0}
.book .narrow{margin-inline:auto}
.book .eyebrow{justify-content:center}
.book h2{margin-inline:auto;font-size:clamp(2.4rem,4.4vw,3.6rem);max-width:none}
.book .lead{margin-inline:auto}
.book .cta-row{justify-content:center;margin-bottom:1.5rem}
.contact-line{color:var(--muted);font-size:.95rem;margin:0}

/* footer */
.site-footer{border-top:1px solid var(--line);padding:3.5rem 0 2rem;font-size:.9rem;color:var(--muted)}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr;gap:2rem;padding-bottom:2.5rem;border-bottom:1px solid var(--line);margin-bottom:1.25rem}
.footer-brand img{height:2rem;width:auto;display:block;margin-bottom:1rem}
.footer-brand p{max-width:28ch;margin:0;color:var(--ink-2)}
.footer-col{display:flex;flex-direction:column;align-items:flex-start;gap:.6rem}
.footer-col a{color:var(--ink-2)}
.footer-col a:hover{color:var(--ink)}
.footer-col b{font-size:.72rem;font-weight:600;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin-bottom:.25rem}
.footer-row{display:flex;justify-content:space-between;flex-wrap:wrap;gap:.5rem;font-size:.84rem}

/* motion: the page's only animations */
.fade-in{animation:fade-in .2s ease-out both}
@keyframes fade-in{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* responsive */
@media (max-width:70rem){
  .facts{font-size:.86rem}
  .facts li{padding:0 1rem}
}
@media (max-width:61.25rem){
  .hero-grid,.about-grid{grid-template-columns:1fr;gap:2.75rem}
  .work-list,.steps{grid-template-columns:1fr;gap:0}
  .work-list article,.steps article{padding:2rem 0;border-left:0}
  .work-list article:first-child,.steps article:first-child{padding-top:0}
  .work-list article+article{border-left:0;border-top:1px solid var(--line)}
  .work-list .surface{order:1;margin:1.25rem 0 0}
  .steps article+article{border-left:0;border-top:1px solid var(--line-dark)}
  .hero-demo{max-width:40rem}
  .constellation{display:none}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1/-1}
}
@media (max-width:45rem){
  body{font-size:1rem}
  .container{width:min(70rem,100% - 2rem);padding-left:env(safe-area-inset-left);padding-right:env(safe-area-inset-right)}
  h1{font-size:clamp(2.4rem,10.5vw,2.9rem);line-height:1.06}
  h2{font-size:clamp(1.9rem,8vw,2.3rem)}
  h3{font-size:1.45rem}
  .lead{font-size:1.1rem;max-width:none}
  .section{padding:4rem 0}
  .section-head{margin-bottom:2rem}
  .eyebrow{margin-bottom:.9rem}
  .hero{padding:2.75rem 0 3.5rem}
  .hero-grid{gap:2.25rem}
  .hero-copy .lead{margin-bottom:1.5em}
  .cta-row{gap:.625rem;margin-bottom:1.75rem}
  .cta-row .btn{flex:1 1 calc(50% - .625rem);padding:.9375rem 1rem}
  .facts{flex-direction:column;gap:.5rem;font-size:.92rem}
  .facts li,.facts li:first-child{border-left:0;padding:0 0 0 1rem;position:relative}
  .facts li::before{content:"";position:absolute;left:0;top:.45em;width:.3rem;height:.3rem;border-radius:50%;background:var(--brass)}
  /* header */
  .nav-row{height:3.75rem}
  .brand-logo{height:2.1rem}
  .nav{position:absolute;top:3.75rem;left:0;right:0;background:var(--paper);border-bottom:1px solid var(--line);box-shadow:0 1rem 2rem -1rem rgba(14,26,51,.25);flex-direction:column;align-items:stretch;padding:.25rem 1rem 1rem;gap:0;display:none}
  .nav.open{display:flex}
  .nav a{padding:.9375rem 0;font-size:1.05rem;border-bottom:1px solid var(--line)}
  .nav a::after{display:none}
  .nav .btn-sm{margin-top:.875rem;padding:.9375rem 1rem;font-size:1rem;border-bottom:0}
  .nav-toggle{display:block;padding:.625rem;margin-right:-.625rem}
  .nav-toggle[aria-expanded="true"] span:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
  .nav-toggle[aria-expanded="true"] span:nth-child(2){opacity:0}
  .nav-toggle[aria-expanded="true"] span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}
  /* chat: fills the phone, bigger tap targets */
  .hero-demo{max-width:none;border-radius:.875rem;box-shadow:0 1.25rem 2.5rem -1.5rem rgba(14,26,51,.35)}
  .demo-bar em{margin-left:.5rem;max-width:none}
  .demo-screen{height:clamp(25rem,100vh - 9rem,30rem)}
  .demo-screen{height:clamp(25rem,100svh - 9rem,30rem)}
  .mock{padding:.875rem}
  .mock-thread{padding:.75rem}
  .mock-msg{max-width:88%}
  .chat-chips{padding-left:0;gap:.5rem}
  .chip{padding:.6rem .95rem;font-size:.88rem}
  .tool{padding:.55rem .95rem;font-size:.82rem}
  .mock-input input{padding:.8rem .875rem}
  .mock-input button{width:3.125rem;height:3.125rem}
  /* proof */
  .proof{padding:2.25rem 0}
  .proof-grid{grid-template-columns:1fr;gap:1.25rem}
  .proof .proof-num{padding-right:0;border-right:0;padding-bottom:1.25rem;border-bottom:1px solid var(--line);font-size:3.4rem}
  .proof p{font-size:.98rem}
  /* work: each system reads as one block */
  .work-list article{padding:1.75rem 0}
  .work-list article:first-child{padding-top:0}
  .surface{min-height:0;margin-top:1rem}
  .s-stats b{font-size:1.2rem}
  /* process: vertical timeline */
  .steps{margin-top:.5rem}
  .steps article,.steps article:first-child{position:relative;padding:0 0 2rem 1.625rem;border-left:1px solid var(--line-dark)}
  .steps article+article{border-top:0}
  .steps article::before{content:"";position:absolute;left:-.3125rem;top:.25rem;width:.5625rem;height:.5625rem;border-radius:50%;background:var(--starlight)}
  .steps article:last-child{padding-bottom:0;border-left-color:transparent}
  .steps .step-num{display:none}
  .step-when{margin-bottom:.5rem}
  .steps h3{font-size:1.45rem}
  /* about, book, footer */
  .about-grid{gap:1.5rem}
  .principles li{padding:.95rem 0 .95rem 2.5rem}
  .principles li::before{top:calc(.95rem + .3em)}
  .book{padding:5rem 0}
  .book .lead{font-size:1.05rem}
  .book .cta-row .btn{flex:0 1 auto;min-width:12rem}
  .site-footer{padding:2.75rem 0 calc(1.5rem + env(safe-area-inset-bottom))}
  .footer-grid{grid-template-columns:1fr;gap:1.75rem;padding-bottom:1.75rem}
  .footer-row{flex-direction:column;gap:.35rem}
}
@media (max-width:22.5rem){
  .cta-row .btn{flex-basis:100%}
  h1{font-size:2.25rem}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important;scroll-behavior:auto}}