.site-header{position:fixed;top:0;left:0;right:0;z-index:1000;background:#000000e6;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-bottom:1px solid rgba(255,255,255,.1);transition:all .3s ease}.nav-container{display:flex;align-items:center;justify-content:space-between;padding:1rem 2rem;max-width:1400px;margin:0 auto;position:relative}.nav-brand{z-index:1001}.brand-link{display:flex;align-items:center;text-decoration:none;transition:all .3s ease}.brand-logo{height:40px;width:auto;max-width:200px;object-fit:contain;transition:all .3s ease}.brand-link:hover{transform:scale(1.05)}.brand-link:hover .brand-logo{filter:brightness(1.1)}.brand-text{color:#fff}.brand-accent{color:#60a5fa;margin-left:2px}.nav-menu{display:flex;align-items:center}.nav-links{display:flex;list-style:none;margin:0;padding:0;gap:2rem}.nav-item{position:relative}.nav-link{display:flex;align-items:center;padding:.5rem 1rem;color:#e5e7eb;text-decoration:none;font-weight:500;border-radius:.5rem;transition:all .3s ease;position:relative;overflow:hidden}.nav-link:before{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,transparent,rgba(96,165,250,.2),transparent);transition:left .5s ease}.nav-link:hover:before{left:100%}.nav-link:hover{color:#60a5fa;background:#60a5fa1a;transform:translateY(-2px)}.nav-link.active{color:#60a5fa;background:#60a5fa26;border:1px solid rgba(96,165,250,.3)}.nav-auth{z-index:1001}.nav-item-auth{display:none}.nav-auth-desktop{display:block}.nav-auth-link{display:flex;align-items:center;gap:.5rem;padding:.75rem 1.5rem;color:#fff;text-decoration:none;font-weight:600;border-radius:2rem;transition:all .3s ease;position:relative;overflow:hidden}.signin-link{background:linear-gradient(135deg,#60a5fa,#3b82f6);box-shadow:0 4px 15px #60a5fa4d}.signin-link:hover{background:linear-gradient(135deg,#3b82f6,#2563eb);transform:translateY(-2px);box-shadow:0 6px 20px #60a5fa66}.profile-link{background:#ffffff1a;border:1px solid rgba(255,255,255,.2)}.profile-link:hover{background:#ffffff26;transform:translateY(-2px)}.profile-link.active{background:#60a5fa26;border-color:#60a5fa4d;color:#60a5fa}.auth-icon{font-size:1.1rem}.auth-text{font-size:.95rem;max-width:120px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.nav-toggle{display:none;flex-direction:column;background:none;border:none;cursor:pointer;padding:.5rem;z-index:1001;transition:all .3s ease}.nav-toggle-line{width:25px;height:3px;background:#fff;margin:3px 0;transition:all .3s ease;border-radius:2px}.nav-toggle.active .nav-toggle-line:nth-child(1){transform:rotate(45deg) translate(6px,6px)}.nav-toggle.active .nav-toggle-line:nth-child(2){opacity:0}.nav-toggle.active .nav-toggle-line:nth-child(3){transform:rotate(-45deg) translate(6px,-6px)}@media (max-width: 768px){.nav-container{padding:1rem}.nav-toggle{display:flex}.nav-menu{position:fixed;top:0;left:0;width:100%;height:100vh;background:#000000f2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);display:flex;flex-direction:column;justify-content:center;align-items:center;padding:6rem 2rem 3rem;transform:translate(-100%);transition:transform .3s ease;z-index:1000}.nav-menu.active{transform:translate(0)}.nav-links{flex-direction:column;gap:2rem;text-align:center;display:flex;justify-content:center;align-items:center}.nav-link{font-size:1.2rem;padding:1rem 2rem;min-width:200px}.nav-auth-desktop{display:none}.nav-item-auth{display:block;margin-top:1rem;border-top:1px solid rgba(255,255,255,.1);padding-top:1rem}.nav-link-auth{background:linear-gradient(135deg,#60a5fa,#3b82f6);color:#fff!important;border-radius:2rem;font-weight:600;box-shadow:0 4px 15px #60a5fa4d;border:none;cursor:pointer;font-family:inherit}.nav-link-auth:hover{background:linear-gradient(135deg,#3b82f6,#2563eb);box-shadow:0 6px 20px #60a5fa66}.nav-link-auth.profile-link{background:#ffffff1a;border:1px solid rgba(255,255,255,.2)}.nav-link-auth.profile-link:hover{background:#ffffff26}}@media (max-width: 480px){.nav-container{padding:.75rem}.brand-logo{height:32px;max-width:150px}.nav-links{gap:1.5rem}.nav-link{font-size:1.1rem;padding:.75rem 1.5rem}}body{padding-top:80px}body:has(canvas#scene){padding-top:0}body:has(canvas#scene) .site-header{background:#000c}body:has(canvas#threejs-canvas){padding-top:0}body:has(canvas#threejs-canvas) .site-header{background:#000c}body:has(.chat-app){padding-top:0}body:has(.chat-app) .site-header{background:#000000f2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px)}body:has(#cesiumContainer){padding-top:0}body:has(#cesiumContainer) .site-header{background:#000000e6}.site-header{animation:slideDown .5s ease-out}@keyframes slideDown{0%{transform:translateY(-100%);opacity:0}to{transform:translateY(0);opacity:1}}@media (prefers-reduced-motion: reduce){.site-header,.nav-link,.nav-auth-link,.nav-toggle-line,.nav-menu{animation:none;transition:none}}.nav-link:focus,.nav-auth-link:focus,.brand-link:focus{outline:2px solid #60a5fa;outline-offset:2px}.nav-toggle:focus{outline:2px solid #60a5fa;outline-offset:4px}.auth-modal-overlay{position:fixed;top:0;left:0;right:0;bottom:0;background:#000000bf;display:flex;align-items:center;justify-content:center;z-index:10000;padding:16px;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);animation:fadeIn .2s ease-out}.auth-modal-overlay.hidden{display:none}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.auth-modal{background:#0c101afa;border:1px solid rgba(255,255,255,.1);border-radius:12px;padding:0;max-width:450px;width:100%;box-shadow:0 20px 40px #00000080;animation:slideUp .3s ease-out;overflow:hidden}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.auth-modal-header{display:flex;align-items:center;justify-content:space-between;padding:24px;border-bottom:1px solid rgba(255,255,255,.1)}.auth-modal-header h2{margin:0;font-size:24px;font-weight:700;color:#e5e7eb}.auth-modal-close{background:none;border:none;color:#94a3b8;font-size:24px;cursor:pointer;padding:0;width:32px;height:32px;display:flex;align-items:center;justify-content:center;border-radius:6px;transition:all .2s ease}.auth-modal-close:hover{background:#ffffff1a;color:#e5e7eb}.auth-modal-body{padding:24px}.auth-modal-body .field{display:grid;gap:8px;margin-bottom:20px}.auth-modal-body .field span{font-weight:600;color:#e5e7eb;font-size:14px}.auth-modal-body .field input{height:44px;border-radius:8px;border:1px solid rgba(255,255,255,.1);background:#0f1627cc;color:#e5e7eb;padding:0 12px;font-size:14px;transition:border-color .2s ease,box-shadow .2s ease;font-family:inherit}.auth-modal-body .field input:focus{outline:none;border-color:#2563eb;box-shadow:0 0 0 3px #2563eb1a}.auth-modal-actions{display:flex;gap:12px;margin-top:8px}.auth-modal-actions .btn{flex:1;height:44px;font-weight:600}.auth-modal-footer{margin-top:16px;text-align:center}.btn-link{background:none;border:none;color:#94a3b8;font-size:14px;cursor:pointer;text-decoration:underline;padding:0;transition:color .2s ease}.btn-link:hover{color:#2563eb}.auth-modal-error{color:#fca5a5;font-size:14px;text-align:center;padding:12px;background:#ef44441a;border-radius:6px;margin-top:16px;border:1px solid rgba(239,68,68,.3)}.auth-modal-error.success{color:#10b981;background:#10b9811a;border-color:#10b9814d}.btn{display:inline-flex;align-items:center;justify-content:center;height:36px;padding:0 14px;border-radius:8px;text-decoration:none;font-weight:600;pointer-events:auto;border:none;cursor:pointer;transition:all .2s ease;font-size:14px}.btn.primary{background:#2563eb;color:#fff;box-shadow:0 8px 24px #2563eb40}.btn.outline{background:transparent;color:#e5e7eb;border:1px solid rgba(255,255,255,.24)}.btn:hover{filter:brightness(1.08);transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn[disabled]{opacity:.7;cursor:not-allowed;filter:none;transform:none}@media (max-width: 600px){.auth-modal{max-width:100%;margin:0}.auth-modal-header,.auth-modal-body{padding:20px}.auth-modal-actions{flex-direction:column}.auth-modal-actions .btn{width:100%}}