*{margin:0;padding:0;box-sizing:border-box}:root{--bg-primary:#1a1a1a;--bg-secondary:#2d2d2d;--bg-tertiary:#3a3a3a;--text-primary:#fff;--text-secondary:#b0b0b0;--text-muted:#888;--accent:#4a9eff;--accent-hover:#3d8bdb;--success:#4caf50;--error:#f44336;--warning:#ff9800;--border:#404040;--shadow:rgba(0,0,0,.3)}body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;background-color:var(--bg-primary);color:var(--text-primary);line-height:1.6;min-height:100vh}.login-page{display:flex;align-items:center;justify-content:center;min-height:100vh;background:linear-gradient(135deg,var(--bg-primary) 0%,var(--bg-secondary) 100%)}.login-container{width:100%;max-width:400px;padding:20px}.login-box{background:var(--bg-secondary);border-radius:12px;padding:40px 30px;box-shadow:0 10px 30px var(--shadow);text-align:center}.login-box h1{font-size:2.5rem;font-weight:700;margin-bottom:10px;background:linear-gradient(135deg,var(--accent),#66b3ff);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.logo-icon{font-size:2.5rem;display:inline-block;margin-right:10px;background:none!important;-webkit-text-fill-color:initial!important}.logo-text{font-size:2rem;font-weight:900;color:var(--accent);background:none!important;-webkit-text-fill-color:var(--accent)!important;border:2px solid var(--accent);padding:2px 8px;border-radius:6px;margin-right:10px;display:inline-block}.subtitle{color:var(--text-secondary);margin-bottom:30px;font-size:1.1rem}.login-form{text-align:left}.form-group{margin-bottom:20px}.form-group label{display:block;margin-bottom:8px;font-weight:500;color:var(--text-secondary)}.form-group input{width:100%;padding:12px 16px;background:var(--bg-tertiary);border:2px solid var(--border);border-radius:8px;color:var(--text-primary);font-size:16px;transition:all .3s ease}.form-group input:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px rgba(74,158,255,.1)}.btn-login{width:100%;padding:14px;background:var(--accent);color:#fff;border:none;border-radius:8px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;margin-bottom:30px}.btn-login:hover{background:var(--accent-hover);transform:translateY(-1px)}.error-message{background:rgba(244,67,54,.1);border:1px solid var(--error);color:var(--error);padding:12px;border-radius:8px;margin-bottom:20px;text-align:center}.demo-users{background:var(--bg-tertiary);padding:20px;border-radius:8px;font-size:.9rem}.demo-users h3{color:var(--text-secondary);margin-bottom:12px;font-size:1rem}.user-demo{margin-bottom:8px;color:var(--text-muted)}.user-demo strong{color:var(--text-primary)}.chat-container{display:flex;flex-direction:column;height:100vh;max-width:1200px;margin:0 auto}.chat-header{background:var(--bg-secondary);padding:20px 30px;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;align-items:center;flex-shrink:0}.header-left h1{font-size:1.8rem;font-weight:700;margin-bottom:5px}.header-left .logo-icon{font-size:1.8rem;margin-right:8px}.user-info{color:var(--text-secondary);font-size:.95rem}.user-level{background:var(--accent);color:#fff;padding:2px 8px;border-radius:12px;font-size:.8rem;font-weight:500;margin-left:8px}.btn-logout{background:var(--bg-tertiary);color:var(--text-primary);padding:10px 20px;border-radius:8px;text-decoration:none;font-weight:500;transition:all .3s ease;border:1px solid var(--border)}.btn-logout:hover{background:var(--error);color:#fff;border-color:var(--error)}.chat-main{flex:1;display:flex;flex-direction:column;min-height:0}.chat-messages{flex:1;overflow-y:auto;padding:30px;scroll-behavior:smooth}.welcome-message{text-align:center;background:var(--bg-secondary);padding:40px 30px;border-radius:12px;margin:50px 0}.welcome-message h2{font-size:2rem;margin-bottom:15px;color:var(--accent)}.welcome-message p{color:var(--text-secondary);font-size:1.1rem}.message-group{margin-bottom:30px}.message{background:var(--bg-secondary);border-radius:12px;padding:20px;margin-bottom:15px;max-width:85%;position:relative}.user-message{margin-left:auto;background:var(--accent);color:#fff}.ai-message{background:var(--bg-secondary);border:1px solid var(--border)}.message-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px;font-size:.9rem}.message-author{font-weight:600}.message-time{opacity:.7}.user-message .message-time{opacity:.8}.message-content{font-size:1rem;line-height:1.5;white-space:pre-wrap}.loading-indicator{display:flex;align-items:center;justify-content:center;padding:20px;background:var(--bg-secondary);margin:20px 30px;border-radius:12px;gap:15px}.loading-dots{display:flex;gap:5px}.loading-dots span{width:8px;height:8px;background:var(--accent);border-radius:50%;animation:loading-bounce 1.4s infinite both}.loading-dots span:nth-child(1) {animation-delay:-.32s}.loading-dots span:nth-child(2) {animation-delay:-.16s}@keyframes loading-bounce {
    0%, 80%, 100% {
        transform: scale(0);
    }
    40% {
        transform: scale(1);
    }
}.chat-form{background:var(--bg-secondary);padding:25px 30px;border-top:1px solid var(--border);display:flex;gap:15px;align-items:flex-end;flex-shrink:0}.chat-form textarea{flex:1;background:var(--bg-tertiary);border:2px solid var(--border);border-radius:12px;padding:15px;color:var(--text-primary);font-size:16px;font-family:inherit;resize:none;min-height:60px;max-height:150px;transition:all .3s ease}.chat-form textarea:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px rgba(74,158,255,.1)}.chat-form textarea::placeholder{color:var(--text-muted)}.chat-form button{background:var(--accent);color:#fff;border:none;border-radius:12px;padding:15px 25px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;gap:8px;min-width:110px;justify-content:center}.chat-form button:hover:not(:disabled) {background:var(--accent-hover);transform:translateY(-1px)}.chat-form button:disabled{opacity:.6;cursor:not-allowed;transform:none}.send-icon{font-size:16px}.chat-messages::-webkit-scrollbar{width:8px}.chat-messages::-webkit-scrollbar-track{background:var(--bg-primary)}.chat-messages::-webkit-scrollbar-thumb{background:var(--border);border-radius:4px}.chat-messages::-webkit-scrollbar-thumb:hover{background:var(--accent)}@media (max-width:768px){.login-box{padding:30px 20px}.chat-header{padding:15px 20px;flex-direction:column;gap:10px;text-align:center}.chat-messages{padding:20px 15px}.message{max-width:95%;padding:15px}.chat-form{padding:20px 15px;flex-direction:column;gap:12px}.chat-form button{align-self:stretch}.welcome-message{margin:20px 0;padding:30px 20px}.welcome-message h2{font-size:1.5rem}}@media (max-width:480px){.login-container{padding:15px}.chat-header h1{font-size:1.5rem}.user-info{font-size:.9rem}.message-content{font-size:.95rem}}.message{animation:fadeInUp .3s ease-out}@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}