:root{
  --bg:#0a0e14; --bg2:#0f151e; --panel:#141c27; --line:#243041;
  --text:#e8edf3; --muted:#a3b0c0; --accent:#ff5a1f; --accent2:#ffb020; --teal:#2fd4c0;
  --est:#2fd4c0; --pilot:#ffb020; --hyp:#b49cff;
  --radius:16px; --maxw:1180px;
  --font:"Inter","Segoe UI",Roboto,"Helvetica Neue",Arial,system-ui,sans-serif;
  --mono:ui-monospace,"SF Mono",Menlo,Consolas,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font:17px/1.65 var(--font);-webkit-font-smoothing:antialiased}
img,video,svg,iframe{display:block;max-width:100%}
a{color:var(--accent2)}
a:hover{color:#ffd27a}
:focus-visible{outline:3px solid var(--accent2);outline-offset:3px;border-radius:6px}
.skip{position:absolute;left:-999px;top:8px;background:var(--accent);color:#000;padding:8px 14px;border-radius:8px;z-index:100}
.skip:focus{left:12px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}
h1,h2,h3{line-height:1.15;letter-spacing:-.02em;margin:0 0 .5em}
h1{font-size:clamp(2.4rem,5.4vw,4.3rem);font-weight:800}
h2{font-size:clamp(1.8rem,3.4vw,2.7rem);font-weight:800;max-width:22ch}
h3{font-size:1.2rem;font-weight:700}
p{margin:0 0 1em}
.accent{background:linear-gradient(90deg,var(--accent),var(--accent2));-webkit-background-clip:text;background-clip:text;color:transparent}
.eyebrow{font:600 .8rem/1 var(--mono);letter-spacing:.16em;text-transform:uppercase;color:var(--accent2);margin-bottom:1rem}
.lede{font-size:1.2rem;color:#cfd8e3;max-width:38ch}
.lede-sm{color:var(--muted);max-width:60ch}
.fine{font-size:.85rem;color:var(--muted)}
.btn{display:inline-flex;align-items:center;gap:.4em;background:linear-gradient(135deg,var(--accent),#ff7a2f);color:#0a0e14;font-weight:700;text-decoration:none;padding:.85em 1.4em;border-radius:999px;border:0;cursor:pointer;font-size:1rem;transition:transform .15s,box-shadow .15s;box-shadow:0 8px 24px -10px rgba(255,90,31,.7)}
.btn:hover{color:#0a0e14;transform:translateY(-1px);box-shadow:0 12px 28px -10px rgba(255,90,31,.9)}
.btn-ghost{background:transparent;color:var(--text);border:1.5px solid #3a4a5e;box-shadow:none}
.btn-ghost:hover{color:var(--text);border-color:var(--accent2)}
.btn-sm{padding:.55em 1.1em;font-size:.9rem}

/* nav */
.nav{position:sticky;top:0;z-index:50;background:rgba(10,14,20,.82);backdrop-filter:blur(10px);border-bottom:1px solid rgba(36,48,65,.7)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:.55em;color:var(--text);text-decoration:none;font-weight:800;font-size:1.2rem;letter-spacing:-.01em}
.brand-mark{width:30px;height:30px;color:var(--text)}
.nav-links{display:flex;align-items:center;gap:1.6rem}
.nav-links a:not(.btn){color:var(--muted);text-decoration:none;font-weight:500;font-size:.95rem}
.nav-links a:not(.btn):hover{color:var(--text)}
.nav-toggle{display:none;background:none;border:1.5px solid #3a4a5e;color:var(--text);border-radius:999px;padding:.4em 1em;font:inherit;font-size:.9rem}

/* hero */
.hero{position:relative;overflow:hidden;padding:72px 0 88px;background:
  radial-gradient(900px 500px at 85% 20%,rgba(255,90,31,.18),transparent 60%),
  radial-gradient(700px 500px at 0% 100%,rgba(47,212,192,.10),transparent 60%),var(--bg)}
.hero-grid{display:grid;grid-template-columns:1.25fr .75fr;gap:56px;align-items:center}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin:28px 0 36px}
.hero-stats{list-style:none;padding:0;margin:0 0 10px;display:flex;gap:36px;flex-wrap:wrap}
.hero-stats li{display:flex;flex-direction:column}
.hero-stats .num{font:700 1.9rem/1.1 var(--mono);color:var(--text)}
.hero-stats .lbl{font-size:.82rem;color:var(--muted);text-transform:uppercase;letter-spacing:.08em}
.hero-media{position:relative;margin:0;justify-self:center;width:100%;max-width:340px}
.hero-video{width:100%;aspect-ratio:9/16;object-fit:cover;border-radius:24px;border:1px solid var(--line);box-shadow:0 40px 80px -30px rgba(0,0,0,.8),0 0 0 8px rgba(255,255,255,.02)}
.hero-media figcaption{font-size:.82rem;color:var(--muted);margin-top:12px;text-align:center}
.orbit{position:absolute;inset:-36px;border-radius:50%;border:1.5px dashed rgba(255,176,32,.25);z-index:-1;animation:spin 40s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}

/* sections */
.section{padding:96px 0}
.section-alt{background:var(--bg2);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.story-grid{display:grid;grid-template-columns:.7fr 1.3fr;gap:64px;align-items:center}
.story-media{margin:0}
.story-media video{width:100%;aspect-ratio:4/5;object-fit:cover;border-radius:var(--radius);border:1px solid var(--line)}
.story-media figcaption{font-size:.82rem;color:var(--muted);margin-top:10px}
.timeline{list-style:none;padding:0;margin:24px 0;border-left:2px solid var(--line)}
.timeline li{display:grid;grid-template-columns:72px 1fr;gap:16px;padding:0 0 18px 20px;position:relative}
.timeline li::before{content:"";position:absolute;left:-7px;top:6px;width:12px;height:12px;border-radius:50%;background:var(--accent);box-shadow:0 0 0 4px rgba(255,90,31,.2)}
.t-year{font:700 1rem var(--mono);color:var(--accent2)}
.callout{background:var(--panel);border:1px solid var(--line);border-left:4px solid var(--pilot);padding:16px 18px;border-radius:12px;color:#d5dde7}

/* badges */
.badge{display:inline-block;font:700 .72rem/1 var(--mono);letter-spacing:.08em;text-transform:uppercase;padding:.45em .7em;border-radius:6px;white-space:nowrap;vertical-align:middle;margin-right:.4em}
.badge-est{background:rgba(47,212,192,.14);color:var(--est);border:1px solid rgba(47,212,192,.45)}
.badge-pilot{background:rgba(255,176,32,.14);color:var(--pilot);border:1px solid rgba(255,176,32,.45)}
.badge-hyp{background:rgba(180,156,255,.14);color:var(--hyp);border:1px solid rgba(180,156,255,.45)}
.badge-calc{background:rgba(255,90,31,.12);color:#ff8a5c;border:1px solid rgba(255,90,31,.45)}

/* physics */
.physics-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:56px;align-items:center;margin-top:12px}
.formula{font:600 1.5rem/1 var(--mono);background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:20px 22px;margin:8px 0 20px;color:var(--text);display:inline-block}
.formula span{color:var(--accent2)}
.formula sub{font-size:.55em;color:var(--muted)}
.diagram{margin:0;background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:18px}
.diagram svg{width:100%;height:auto}
.diagram text{font-family:var(--font)}
.diagram figcaption{color:var(--muted);font-size:.85rem;text-align:center;margin-top:6px}

.calc{margin:64px 0 48px;background:linear-gradient(180deg,#151e2a,#111823);border:1px solid var(--line);border-radius:20px;padding:32px}
.calc-head{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-bottom:18px}
.calc-head h3{margin:0;font-size:1.45rem}
.calc-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:36px;align-items:center}
.calc label{display:flex;justify-content:space-between;font-weight:600;margin:6px 0 8px;color:#d5dde7}
.calc output{font-family:var(--mono);color:var(--accent2)}
input[type=range]{width:100%;accent-color:var(--accent);height:28px;margin:0 0 14px}
.readouts{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:8px 0 0}
.readouts div{background:#0d131b;border:1px solid var(--line);border-radius:12px;padding:12px 14px}
.readouts dt{font-size:.78rem;color:var(--muted);text-transform:uppercase;letter-spacing:.06em}
.readouts dd{margin:2px 0 0;font:700 1.4rem var(--mono);color:var(--text)}
.readouts small{font-size:.7em;color:var(--muted)}
.calc-chart svg{width:100%;height:auto}
.calc .fine{margin:20px 0 0;max-width:110ch}

.cards{display:grid;gap:20px}
.cards-3{grid-template-columns:repeat(3,1fr)}
.cards-4{grid-template-columns:repeat(4,1fr);margin-top:28px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:24px}
.card p{color:#c3cdd9;margin:0}
.config-note{color:var(--muted);max-width:80ch;margin:20px 0 64px}
.aud{display:flex;flex-direction:column}
.aud svg{width:34px;height:34px;color:var(--accent);margin-bottom:14px}
.aud p{flex:1;margin-bottom:16px}
.aud a{font-weight:700;text-decoration:none}
.split{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center}
.ticks{list-style:none;padding:0;margin:0 0 28px}
.ticks li{position:relative;padding-left:26px;margin-bottom:10px;color:#c9d3de}
.ticks li::before{content:"";position:absolute;left:0;top:.55em;width:12px;height:12px;border-radius:3px;background:linear-gradient(135deg,var(--accent),var(--accent2))}
.render{margin:0}
.render img{border-radius:var(--radius);border:1px solid var(--line);width:100%;height:auto}
.render figcaption{font-size:.82rem;color:var(--muted);margin-top:10px}

/* evidence */
.legend{display:flex;flex-wrap:wrap;align-items:center;gap:6px 14px;color:var(--muted);font-size:.9rem;margin:20px 0 30px}
.evidence{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:1fr 1fr;gap:18px}
.evidence li{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:22px 24px}
.evidence li:last-child:nth-child(odd){grid-column:1/-1}
.evidence li .badge{margin-bottom:12px}
.evidence h3{font-size:1.1rem}
.evidence h3 small{display:block;font-weight:500;font-size:.8rem;color:var(--muted);margin-top:4px;letter-spacing:0}
.evidence p{color:#c3cdd9;margin-bottom:.6em}
.cite{font-size:.82rem;color:var(--muted)!important}

/* specs */
.specs{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;margin:28px 0 12px}
.specs div{background:var(--panel);padding:24px}
.specs dt{font:600 .75rem var(--mono);text-transform:uppercase;letter-spacing:.1em;color:var(--muted)}
.specs dd{margin:8px 0 0;font-size:1.25rem;font-weight:700}

/* videos */
.vo2{display:grid;grid-template-columns:.8fr 1.2fr;gap:36px;align-items:center;background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:28px;margin:28px 0 56px}
.vo2 h3{font-size:1.6rem;margin-top:10px}
.vo2-frame{aspect-ratio:16/9;border-radius:14px;overflow:hidden;background:#000;border:1px solid var(--line)}
.vo2-frame iframe{width:100%;height:100%;border:0}
.sub{margin:0 0 18px;color:var(--text)}
.vgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-bottom:48px}
.vcard{margin:0;background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}
.vcard video{width:100%;aspect-ratio:9/16;object-fit:cover;background:#000;max-height:560px}
.vcard figcaption{padding:14px 16px 18px;color:#c3cdd9;font-size:.93rem}
.vcard figcaption strong{display:block;color:var(--text);margin-bottom:2px}

/* contact */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:start}
address{font-style:normal;line-height:1.9;margin-top:20px;font-size:1.05rem}
.form{background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:28px;display:flex;flex-direction:column}
.form label{font-weight:600;margin:14px 0 6px;font-size:.95rem}
.form label:first-child{margin-top:0}
.opt{color:var(--muted);font-weight:400}
.form input,.form select,.form textarea{background:#0d131b;color:var(--text);border:1px solid #33435a;border-radius:10px;padding:12px 14px;font:inherit;font-size:1rem}
.form input:focus,.form select:focus,.form textarea:focus{border-color:var(--accent2);outline:none;box-shadow:0 0 0 3px rgba(255,176,32,.25)}
.form .btn{margin-top:20px;align-self:flex-start}
.form .fine{margin:12px 0 0}

.footer{border-top:1px solid var(--line);padding:28px 0;color:var(--muted);font-size:.9rem}
.footer-inner{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap}
.footer a{color:var(--muted)}

/* responsive */
@media (max-width:980px){
  .hero-grid,.story-grid,.physics-grid,.calc-grid,.split,.contact-grid,.vo2{grid-template-columns:1fr}
  .hero-media{max-width:300px}
  .story-media{max-width:420px}
  .cards-4{grid-template-columns:1fr 1fr}
  .specs{grid-template-columns:repeat(2,1fr)}
  .evidence{grid-template-columns:1fr}
}
@media (max-width:760px){
  body{font-size:16px}
  .section{padding:68px 0}
  .hero{padding:44px 0 64px}
  .nav-toggle{display:block}
  .nav-links{display:none;position:absolute;top:68px;left:0;right:0;flex-direction:column;align-items:flex-start;gap:0;background:#0d131b;border-bottom:1px solid var(--line);padding:8px 24px 20px}
  .nav-links.open{display:flex}
  .nav-links a{padding:12px 0;width:100%}
  .nav-links .btn{width:auto;margin-top:8px;padding:.6em 1.2em}
  .cards-3,.cards-4,.vgrid{grid-template-columns:1fr}
  .vcard video{max-height:520px}
  .hero-stats{gap:24px}
  .readouts{grid-template-columns:1fr 1fr}
  .calc{padding:22px}
  .timeline li{grid-template-columns:56px 1fr}
  .formula{font-size:1.15rem}
  .hero-media{max-width:250px}
  .orbit{display:none}
  .hero-stats{display:grid;grid-template-columns:repeat(3,auto);gap:14px;justify-content:start}
  .hero-stats .num{font-size:1.35rem}
  .hero-stats .lbl{font-size:.7rem}
  .story-media video{aspect-ratio:1/1}
  .vcard video{aspect-ratio:4/5;max-height:none}
  .readouts dd{font-size:1.2rem}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .orbit{animation:none}
  *{transition:none!important}
}