:root{
  color-scheme:dark;
  --bg:#07101d;
  --panel:#0c1726;
  --panel2:#0a1421;
  --line:rgba(255,255,255,.09);
  --line2:rgba(118,217,255,.18);
  --text:#f2f6fb;
  --muted:#8fa0b5;
  --cyan:#73dcff;
  --cyan2:#45bfe9;
  --green:#67e5b5;
  --shadow:0 20px 70px rgba(0,0,0,.33);
}
*{box-sizing:border-box}
html{background:var(--bg);scrollbar-color:#30455b #07101d}
body{margin:0;min-height:100vh;font:14px/1.5 Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--text);background:
radial-gradient(900px 500px at 70% -20%,rgba(48,176,222,.16),transparent 60%),
radial-gradient(600px 400px at 5% 30%,rgba(38,100,160,.10),transparent 65%),var(--bg)}
button,input{font:inherit}
button{cursor:pointer}
.topbar{height:70px;display:flex;align-items:center;gap:28px;padding:0 max(24px,calc((100vw - 1500px)/2));border-bottom:1px solid var(--line);background:rgba(5,13,24,.72);backdrop-filter:blur(16px);position:sticky;top:0;z-index:20}
.brand{display:flex;align-items:center;gap:10px;color:#dce7f2;text-decoration:none;letter-spacing:-.01em}.brand strong{color:white}.brand-mark{display:grid;place-items:center;width:30px;height:30px;border:1px solid rgba(115,220,255,.35);background:linear-gradient(145deg,rgba(115,220,255,.15),rgba(115,220,255,.02));color:var(--cyan);font-weight:800;border-radius:7px}
.crumb{color:var(--muted);font-size:13px}.crumb span{padding:0 8px;color:#52657c}.status{margin-left:auto;color:#a9b9ca;font-size:12px;text-transform:uppercase;letter-spacing:.12em;display:flex;align-items:center;gap:8px}.status i{width:7px;height:7px;border-radius:50%;background:var(--green);box-shadow:0 0 18px rgba(103,229,181,.8)}
.app-shell{width:min(1500px,calc(100% - 48px));margin:0 auto;padding:62px 0 38px}.intro{display:flex;align-items:flex-end;justify-content:space-between;gap:30px;margin-bottom:30px}.eyebrow,.kicker{font-size:11px;font-weight:700;letter-spacing:.18em;color:var(--cyan);margin:0 0 12px}.intro h1{font-size:clamp(34px,4vw,62px);line-height:1.02;letter-spacing:-.045em;margin:0 0 16px;max-width:800px}.lede{color:#a6b5c5;font-size:16px;max-width:700px;margin:0}.intro-actions{display:flex;gap:10px;flex-wrap:wrap;justify-content:flex-end}
.button{appearance:none;border:1px solid var(--line);border-radius:8px;padding:11px 16px;color:#eaf3fa;background:#101d2c;transition:.18s ease;font-weight:650;box-shadow:none}.button:hover{transform:translateY(-1px);border-color:rgba(115,220,255,.3)}.button.primary{background:linear-gradient(180deg,#77ddff,#4bbddf);border-color:#7be2ff;color:#04101a;box-shadow:0 8px 30px rgba(68,190,228,.16)}.button.primary:hover{filter:brightness(1.05)}.button.ghost{background:rgba(255,255,255,.025)}.button.wide{width:100%;margin-top:10px;padding:13px 16px}
.workspace{display:grid;grid-template-columns:290px minmax(440px,1fr) 260px;min-height:0;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:rgba(8,17,29,.62);box-shadow:var(--shadow)}
.panel{background:linear-gradient(180deg,rgba(13,26,42,.96),rgba(9,20,33,.96));padding:22px}.controls{border-right:1px solid var(--line);max-height:690px;overflow:auto}.export-panel{border-left:1px solid var(--line);max-height:690px;overflow:auto}.panel-title{display:flex;align-items:flex-start;justify-content:space-between;margin-bottom:20px}.panel-title .kicker{display:block;margin-bottom:2px}.panel-title h2{font-size:19px;margin:0;letter-spacing:-.02em}.icon-button{border:1px solid var(--line);border-radius:7px;background:rgba(255,255,255,.025);color:#8fa7bc;padding:6px 8px}.icon-button:hover{color:white;border-color:var(--line2)}
.control-section{padding:17px 0;border-top:1px solid var(--line)}.control-section h3{margin:0 0 14px;text-transform:uppercase;letter-spacing:.12em;font-size:10px;color:#6f8297}.control{display:block;margin:0 0 17px}.control:last-child{margin-bottom:0}.control>span{display:flex;justify-content:space-between;gap:10px;color:#b9c6d3;font-size:12px;margin-bottom:8px}.control output{color:#eff9ff;font-variant-numeric:tabular-nums}.control[data-unit="mm"] output::after{content:" mm";color:#687c91}.control[data-unit="deg"] output::after{content:"°";color:#687c91}
input[type=range]{width:100%;height:3px;appearance:none;border-radius:20px;background:linear-gradient(90deg,#3db5e0 var(--fill,50%),#25384a var(--fill,50%));outline:none}input[type=range]::-webkit-slider-thumb{appearance:none;width:13px;height:13px;border-radius:50%;background:#e9f9ff;border:2px solid #5ac8ef;box-shadow:0 0 0 4px rgba(90,200,239,.10)}input[type=range]::-moz-range-thumb{width:10px;height:10px;border-radius:50%;background:#e9f9ff;border:2px solid #5ac8ef}
.viewer-card{position:relative;height:690px;min-height:0;min-width:0;background:
linear-gradient(rgba(115,220,255,.025) 1px,transparent 1px),
linear-gradient(90deg,rgba(115,220,255,.025) 1px,transparent 1px),
radial-gradient(circle at 50% 43%,rgba(54,160,211,.14),transparent 42%),#07111d;background-size:32px 32px,32px 32px,auto,auto;overflow:hidden}#glCanvas{position:absolute;inset:0;width:100%;height:100%;display:block;touch-action:none}.viewer-card:after{content:"";position:absolute;inset:0;pointer-events:none;background:radial-gradient(circle at center,transparent 48%,rgba(4,10,18,.38) 100%)}.viewer-overlay{position:absolute;z-index:2;color:#71869b;font-size:11px;letter-spacing:.04em;pointer-events:none}.top-left{left:18px;top:16px;display:flex;align-items:center;gap:10px}.bottom-left{left:18px;bottom:14px}.badge{border:1px solid rgba(103,229,181,.2);background:rgba(103,229,181,.07);color:#86e9c4;border-radius:999px;padding:4px 8px;font-size:9px;letter-spacing:.14em}.axis{position:absolute;right:18px;bottom:18px;z-index:2;width:42px;height:42px;color:#678097;font-size:9px}.axis span{position:absolute;left:20px;bottom:12px;width:1px;height:26px;background:#4f7693;transform:rotate(-18deg);transform-origin:bottom}.axis b{position:absolute;left:7px;top:-4px;color:#78dfff}.axis em{font-style:normal;position:absolute;right:-3px;bottom:0}
.segmented{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--line);border-radius:8px;overflow:hidden;background:#08131f}.segment{border:0;background:transparent;color:#7f93a8;padding:10px 7px;font-size:11px;font-weight:700}.segment.active{background:rgba(115,220,255,.10);color:#dff7ff;box-shadow:inset 0 0 0 1px rgba(115,220,255,.14)}.help{color:#8093a8;font-size:12px;min-height:54px;margin:13px 0 18px}.hidden{display:none!important}.metric-grid{display:grid;grid-template-columns:1fr 1fr;gap:1px;background:var(--line);border:1px solid var(--line);border-radius:9px;overflow:hidden;margin:4px 0 20px}.metric-grid>div{background:#0a1725;padding:12px 10px}.metric-grid span{display:block;color:#6c8197;font-size:10px;text-transform:uppercase;letter-spacing:.08em;margin-bottom:3px}.metric-grid strong{font-size:13px;font-variant-numeric:tabular-nums}.export-note{border-left:2px solid rgba(115,220,255,.5);padding:9px 0 9px 12px;margin:18px 0;color:#aab9c7}.export-note strong{display:block;color:#ddebF6;font-size:12px}.export-note p{font-size:11px;margin:3px 0 0;color:#74889d}
.about-strip{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:12px;overflow:hidden;margin-top:24px}.about-strip>div{background:rgba(8,18,30,.85);padding:19px 22px}.about-strip span{font-size:10px;color:#5cccf3;margin-right:11px}.about-strip strong{font-size:13px}.about-strip p{margin:6px 0 0;color:#70859a;font-size:12px}
footer{width:min(1500px,calc(100% - 48px));margin:0 auto;padding:0 0 34px;color:#50657a;font-size:11px}.toast{position:fixed;right:24px;bottom:24px;z-index:50;transform:translateY(20px);opacity:0;pointer-events:none;background:#102235;border:1px solid rgba(115,220,255,.22);box-shadow:0 15px 60px rgba(0,0,0,.4);padding:11px 14px;border-radius:8px;color:#d8ecf7;transition:.2s ease;font-size:12px}.toast.show{opacity:1;transform:none}
@media(max-width:1100px){.workspace{grid-template-columns:260px 1fr}.export-panel{grid-column:1/-1;border-left:0;border-top:1px solid var(--line);display:grid;grid-template-columns:230px 1fr 1fr;gap:18px;align-items:start}.export-panel .panel-title{grid-column:1/-1;margin-bottom:0}.export-panel .metric-grid{margin:0}.export-panel .button.wide{margin-top:0}.viewer-card{height:620px;min-height:0}}
@media(max-width:760px){.app-shell{width:min(100% - 24px,1500px);padding-top:34px}.topbar{height:60px;padding:0 14px}.crumb{display:none}.intro{display:block}.intro-actions{justify-content:flex-start;margin-top:22px}.workspace{display:block}.controls{max-height:none;border-right:0;border-bottom:1px solid var(--line)}.viewer-card{height:520px;min-height:0}.export-panel{display:block;border-top:1px solid var(--line)}.about-strip{grid-template-columns:1fr}footer{width:calc(100% - 24px)}}
.captcha-backdrop{position:fixed;inset:0;z-index:100;display:none;place-items:center;padding:20px;background:rgba(2,8,15,.78);backdrop-filter:blur(10px)}.captcha-backdrop.visible{display:grid}.captcha-card{width:min(420px,100%);border:1px solid var(--line2);border-radius:14px;background:#0b1725;box-shadow:0 30px 100px rgba(0,0,0,.55);padding:24px}.captcha-card h3{margin:3px 0 7px;font-size:22px}.captcha-card p{margin:0 0 18px;color:var(--muted)}#captchaWidget{min-height:70px;margin:10px 0 16px}.busy{opacity:.65;pointer-events:none}

/* Frontend 1.2: stable preview viewport and serialized preview feedback. */
.viewer-card{contain:layout paint}
.viewer-card:before{content:"UPDATING PREVIEW";position:absolute;z-index:4;right:18px;top:16px;padding:5px 9px;border:1px solid rgba(115,220,255,.18);border-radius:999px;background:rgba(7,17,29,.82);color:#79cce8;font-size:9px;font-weight:750;letter-spacing:.13em;opacity:0;transform:translateY(-3px);transition:opacity .16s ease,transform .16s ease;pointer-events:none}
.viewer-card.is-loading:before{opacity:1;transform:none}
.viewer-card.is-loading #glCanvas{filter:saturate(.92) brightness(.93)}
#glCanvas{transition:filter .18s ease}
@media(max-width:1100px){.controls{max-height:620px}.export-panel{max-height:none;overflow:visible}}
@media(max-width:760px){.controls{max-height:none}.export-panel{max-height:none;overflow:visible}}

.quality-note{margin:2px 0 0;color:#6f8499;font-size:11px;line-height:1.55}