:root{color-scheme:dark;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,sans-serif}*{box-sizing:border-box}html,body{margin:0;height:100%;background:radial-gradient(circle at 20% 20%,#171f31,#0a0d16 45%,#07090f);color:#eef4ff}body{overflow:hidden}.app-shell{position:relative;width:100vw;height:100vh}.viewer{width:100%;height:100%;cursor:grab}.viewer:active{cursor:grabbing}.overlay{position:absolute;inset:0;display:grid;place-items:center;background:#030814c7;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);z-index:3}.welcome-overlay .panel{width:min(640px,92vw);border:1px solid rgba(183,198,255,.2);background:linear-gradient(170deg,#141b30e6,#0a0d19eb);border-radius:22px;padding:clamp(1.2rem,2.5vw,2rem);box-shadow:0 20px 50px #00000073}.eyebrow{color:#8db4ff;letter-spacing:.08em;font-size:.8rem;text-transform:uppercase}h1{margin:.35rem 0 1rem;line-height:1.2;font-size:clamp(1.4rem,4vw,2rem)}.btn{border:1px solid rgba(171,194,255,.24);background:#2b3a60cc;color:#eef4ff;border-radius:12px;padding:.62rem .95rem;font-size:.95rem;cursor:pointer;transition:transform .15s ease,background .2s ease}.btn:hover{transform:translateY(-1px);background:#445890e0}.btn-primary{display:inline-block;margin-top:.5rem;background:linear-gradient(120deg,#4f7fff,#57b2ff);color:#081327;border:none;font-weight:700}.controls{position:absolute;left:50%;bottom:1rem;transform:translate(-50%);z-index:2;display:flex;gap:.7rem;flex-wrap:wrap;justify-content:center;padding:.65rem;border-radius:14px;background:#070a169e;border:1px solid rgba(173,192,255,.22)}.loading-overlay{display:grid;gap:.8rem;place-items:center}.spinner{width:46px;height:46px;border-radius:50%;border:4px solid rgba(255,255,255,.25);border-top-color:#69abff;animation:spin .85s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.toast{position:absolute;top:1rem;left:50%;transform:translate(-50%);z-index:5;width:min(95vw,760px);padding:.85rem 1rem;border-radius:12px;border:1px solid rgba(255,179,120,.5);background:#301603eb;color:#ffd8b7;text-align:center}.hidden{display:none!important}@media(max-width:640px){.controls{width:calc(100vw - 1rem);bottom:.5rem}.btn{flex:1 1 auto}}