:root{--bg-primary:#0d1117;--bg-secondary:#161b22;--bg-tertiary:#21262d;--bg-hover:#30363d;--bg-active:#1c2333;--border:#30363d;--border-light:#484f58;--text-primary:#e6edf3;--text-secondary:#8b949e;--text-muted:#6e7681;--accent:#58a6ff;--accent-hover:#79c0ff;--accent-glow:rgba(88,166,255,.15);--success:#3fb950;--warning:#d29922;--danger:#f85149;--nostr-orange:#f97316;--nostr-orange-dim:rgba(249,115,22,.15);--radius-sm:6px;--radius-md:10px;--radius-lg:16px;--radius-xl:24px;--shadow-sm:0 1px 2px rgba(0,0,0,.3);--shadow-md:0 4px 12px rgba(0,0,0,.4);--shadow-lg:0 8px 24px rgba(0,0,0,.5);--transition:.2s ease}*{box-sizing:border-box;margin:0;padding:0}html,body{background:var(--bg-primary);height:100%;color:var(--text-primary);-webkit-font-smoothing:antialiased;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Inter,Roboto,Helvetica,Arial,sans-serif;line-height:1.5}.login-page{background:radial-gradient(ellipse at top, rgba(88,166,255,.05) 0%, transparent 60%), var(--bg-primary);justify-content:center;align-items:center;min-height:100vh;padding:24px;display:flex}.login-card{background:var(--bg-secondary);border:1px solid var(--border);border-radius:var(--radius-xl);text-align:center;width:100%;max-width:440px;box-shadow:var(--shadow-lg);padding:48px 40px;animation:.5s fadeInUp}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.login-icon{margin-bottom:16px;font-size:56px;animation:3s ease-in-out infinite float}@keyframes float{0%,to{transform:translateY(0)}50%{transform:translateY(-6px)}}.login-title{background:linear-gradient(135deg, var(--text-primary), var(--accent));-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text;margin-bottom:8px;font-size:32px;font-weight:700}.login-subtitle{color:var(--text-secondary);margin-bottom:24px;font-size:16px}.login-description{color:var(--text-muted);margin-bottom:32px;font-size:14px;line-height:1.6}.login-features{flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:32px;display:flex}.feature{background:var(--bg-tertiary);border-radius:var(--radius-lg);color:var(--text-secondary);border:1px solid var(--border);align-items:center;gap:6px;padding:8px 14px;font-size:13px;display:flex}.feature-icon{font-size:16px}.login-button{color:#fff;background:linear-gradient(135deg, var(--nostr-orange), #ea580c);border-radius:var(--radius-md);cursor:pointer;width:100%;transition:all var(--transition);box-shadow:var(--shadow-sm);border:none;padding:14px 24px;font-size:16px;font-weight:600}.login-button:hover:not(:disabled){transform:translateY(-1px);box-shadow:0 4px 16px rgba(249,115,22,.3)}.login-button:active:not(:disabled){transform:translateY(0)}.login-button:disabled{opacity:.6;cursor:not-allowed}.login-error{border-radius:var(--radius-md);color:var(--danger);background:rgba(248,81,73,.1);border:1px solid rgba(248,81,73,.3);margin-top:16px;padding:12px;font-size:13px}.login-hint{color:var(--text-muted);margin-top:20px;font-size:12px}.chat-layout{height:100vh;display:flex;overflow:hidden}.sidebar{background:var(--bg-secondary);border-right:1px solid var(--border);flex-direction:column;gap:20px;width:280px;min-width:280px;padding:20px 16px;display:flex;overflow-y:auto}.sidebar-header{align-items:center;gap:10px;padding:0 4px;display:flex}.sidebar-logo{font-size:28px}.sidebar-title{background:linear-gradient(135deg, var(--text-primary), var(--accent));-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text;font-size:20px;font-weight:700}.sidebar-section{flex-direction:column;gap:8px;display:flex}.sidebar-label{text-transform:uppercase;letter-spacing:.08em;color:var(--text-muted);padding:0 4px;font-size:11px;font-weight:600}.sidebar-select{background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-md);width:100%;color:var(--text-primary);cursor:pointer;transition:border-color var(--transition);padding:10px 12px;font-size:14px}.sidebar-select:focus{border-color:var(--accent);box-shadow:0 0 0 2px var(--accent-glow);outline:none}.sidebar-select option{background:var(--bg-secondary);color:var(--text-primary)}.language-options{flex-direction:column;gap:6px;display:flex}.language-btn{border:1px solid var(--border);border-radius:var(--radius-md);width:100%;color:var(--text-secondary);cursor:pointer;transition:all var(--transition);text-align:left;background:0 0;align-items:center;gap:10px;padding:10px 12px;font-size:14px;display:flex}.language-btn:hover{background:var(--bg-hover);color:var(--text-primary);border-color:var(--border-light)}.language-btn.active{background:var(--accent-glow);border-color:var(--accent);color:var(--accent)}.lang-flag{font-size:18px}.level-options{gap:6px;display:flex}.level-btn{border:1px solid var(--border);border-radius:var(--radius-md);color:var(--text-secondary);cursor:pointer;transition:all var(--transition);background:0 0;flex-direction:column;flex:1;align-items:center;gap:4px;padding:10px 8px;font-size:12px;display:flex}.level-btn:hover{background:var(--bg-hover);color:var(--text-primary)}.level-btn.active{background:var(--accent-glow);border-color:var(--accent);color:var(--accent)}.level-icon{font-size:18px}.sidebar-actions{border-top:1px solid var(--border);flex-direction:column;gap:8px;margin-top:auto;padding-top:16px;display:flex}.new-chat-btn{background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-md);width:100%;color:var(--text-primary);cursor:pointer;transition:all var(--transition);padding:10px;font-size:14px;font-weight:500}.new-chat-btn:hover{background:var(--bg-hover);border-color:var(--accent);color:var(--accent)}.logout-btn{border-radius:var(--radius-md);width:100%;color:var(--text-muted);cursor:pointer;transition:all var(--transition);background:0 0;border:none;padding:8px;font-size:13px}.logout-btn:hover{color:var(--danger);background:rgba(248,81,73,.08)}.chat-main{background:var(--bg-primary);flex-direction:column;flex:1;display:flex;overflow:hidden}.chat-container{flex-direction:column;flex:1;width:100%;max-width:800px;margin:0 auto;padding:0 24px;display:flex}.welcome-screen{text-align:center;flex-direction:column;flex:1;justify-content:center;align-items:center;padding:40px 20px;animation:.4s fadeInUp;display:flex}.welcome-icon{margin-bottom:20px;font-size:64px}.welcome-title{color:var(--text-primary);margin-bottom:12px;font-size:28px;font-weight:700}.welcome-desc{color:var(--text-secondary);max-width:400px;margin-bottom:8px;font-size:16px}.welcome-level{color:var(--text-muted);margin-bottom:32px;font-size:14px}.start-btn{color:#fff;background:linear-gradient(135deg, var(--accent), #3b82f6);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition);box-shadow:var(--shadow-sm);border:none;padding:14px 32px;font-size:16px;font-weight:600}.start-btn:hover{transform:translateY(-1px);box-shadow:0 4px 16px rgba(88,166,255,.3)}.start-btn:active{transform:translateY(0)}.messages-area{scroll-behavior:smooth;flex-direction:column;flex:1;gap:16px;padding:24px 0;display:flex;overflow-y:auto}.messages-area::-webkit-scrollbar{width:6px}.messages-area::-webkit-scrollbar-track{background:0 0}.messages-area::-webkit-scrollbar-thumb{background:var(--bg-hover);border-radius:3px}.message-row{gap:12px;max-width:85%;animation:.3s fadeIn;display:flex}.message-row.user{flex-direction:row-reverse;align-self:flex-end}.message-row.user .message-bubble{background:linear-gradient(135deg, var(--accent), #3b82f6);color:#fff;border-radius:var(--radius-lg) var(--radius-lg) 4px var(--radius-lg)}.message-row.user .message-avatar{background:var(--accent-glow)}.message-row.assistant{align-self:flex-start}.message-row.assistant .message-bubble{background:var(--bg-secondary);border:1px solid var(--border);border-radius:var(--radius-lg) var(--radius-lg) var(--radius-lg) 4px}.message-row.assistant .message-avatar{background:var(--bg-tertiary)}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.message-avatar{border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:36px;height:36px;font-size:16px;display:flex}.message-bubble{word-wrap:break-word;padding:12px 16px;font-size:14px;line-height:1.6}.message-content{white-space:pre-wrap}.typing{padding:16px 20px}.typing-dots{align-items:center;gap:4px;display:flex}.typing-dots span{background:var(--text-muted);border-radius:50%;width:8px;height:8px;animation:1.4s infinite typingBounce}.typing-dots span:nth-child(2){animation-delay:.2s}.typing-dots span:nth-child(3){animation-delay:.4s}@keyframes typingBounce{0%,60%,to{opacity:.4;transform:translateY(0)}30%{opacity:1;transform:translateY(-6px)}}.chat-input-form{padding:16px 0 24px}.input-wrapper{background:var(--bg-secondary);border:1px solid var(--border);border-radius:var(--radius-lg);transition:border-color var(--transition);align-items:center;gap:10px;padding:6px 6px 6px 18px;display:flex}.input-wrapper:focus-within{border-color:var(--accent);box-shadow:0 0 0 2px var(--accent-glow)}.chat-input{color:var(--text-primary);background:0 0;border:none;outline:none;flex:1;padding:8px 0;font-size:15px}.chat-input::placeholder{color:var(--text-muted)}.chat-input:disabled{opacity:.5}.send-btn{border-radius:var(--radius-md);background:linear-gradient(135deg, var(--accent), #3b82f6);color:#fff;cursor:pointer;width:40px;height:40px;transition:all var(--transition);border:none;flex-shrink:0;justify-content:center;align-items:center;font-size:18px;display:flex}.send-btn:hover:not(:disabled){transform:scale(1.05);box-shadow:0 2px 8px rgba(88,166,255,.3)}.send-btn:active:not(:disabled){transform:scale(.95)}.send-btn:disabled{opacity:.4;cursor:not-allowed}@media (width<=768px){.sidebar{width:100%;min-width:unset;border-right:none;border-top:1px solid var(--border);z-index:100;flex-flow:wrap;gap:12px;height:auto;max-height:50vh;padding:12px;position:fixed;bottom:0;left:0;right:0;overflow-y:auto}.sidebar-header{width:100%}.sidebar-section{flex:1;min-width:120px}.sidebar-actions{border-top:none;flex-direction:row;width:100%;margin-top:0}.chat-main{padding-bottom:200px}.message-row{max-width:95%}.login-card{padding:32px 24px}}