:root{--bg:#0a0a0f;--bg-secondary:#12121a;--bg-tertiary:#1a1a28;--bg-card:#16161f;--border:#2a2a3d;--border-light:#3a3a52;--text:#e8e8f0;--text-secondary:#9898b0;--text-muted:#6a6a85;--accent:#7c5cff;--accent-light:#9b7fff;--accent-glow:rgba(124,92,255,.15);--accent-gradient:linear-gradient(135deg,#7c5cff,#5c8cff);--green:#4ade80;--orange:#fb923c;--red:#f87171;--blue:#60a5fa;--radius:12px;--radius-sm:8px;--shadow:0 4px 24px rgba(0,0,0,.3);--font:"Inter",-apple-system,BlinkMacSystemFont,sans-serif;--font-mono:"JetBrains Mono",monospace}*{margin:0;padding:0;box-sizing:border-box}body,html{font-family:var(--font);background:var(--bg);color:var(--text);min-height:100vh;-webkit-font-smoothing:antialiased}a{color:var(--accent-light);text-decoration:none}a:hover{text-decoration:underline}button{cursor:pointer;border:none}button,input,textarea{font-family:var(--font);outline:none}::selection{background:var(--accent);color:#fff}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}::-webkit-scrollbar-thumb:hover{background:var(--border-light)}.landing{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:2rem;background:radial-gradient(ellipse at 50% 0,rgba(124,92,255,.08) 0,transparent 60%)}.landing-logo{font-size:3rem;font-weight:700;background:var(--accent-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;margin-bottom:.5rem}.landing-sub{color:var(--text-secondary);font-size:1.15rem;max-width:480px;text-align:center;line-height:1.6;margin-bottom:2.5rem}.google-btn{display:flex;align-items:center;gap:12px;background:#fff;color:#333;font-weight:600;font-size:1rem;padding:14px 32px;border-radius:50px;box-shadow:0 2px 12px rgba(0,0,0,.2);transition:transform .15s,box-shadow .15s}.google-btn:hover{transform:translateY(-1px);box-shadow:0 4px 20px rgba(0,0,0,.3);text-decoration:none}.google-btn svg{width:20px;height:20px}.features{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:1.5rem;gap:1.5rem;max-width:720px;margin-top:4rem}.feature-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem}.feature-card h3{font-size:.95rem;font-weight:600;margin-bottom:.5rem}.feature-card p{font-size:.85rem;color:var(--text-secondary);line-height:1.5}.dashboard{display:grid;grid-template-columns:1fr 380px;min-height:100vh}.main-panel{display:flex;flex-direction:column;border-right:1px solid var(--border)}.topbar{display:flex;align-items:center;justify-content:space-between;padding:16px 24px;border-bottom:1px solid var(--border);background:var(--bg-secondary)}.topbar-brand{font-size:1.2rem;font-weight:700;background:var(--accent-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent}.topbar-user{display:flex;align-items:center;gap:10px}.topbar-user img{width:32px;height:32px;border-radius:50%}.topbar-user span{font-size:.9rem;color:var(--text-secondary)}.search-area{flex:1 1;display:flex;flex-direction:column;padding:24px;overflow-y:auto}.search-box{position:relative;margin-bottom:24px}.search-box textarea{width:100%;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius);color:var(--text);font-size:1rem;padding:16px 60px 16px 20px;resize:none;min-height:80px;transition:border-color .2s}.search-box textarea:focus{border-color:var(--accent)}.search-box textarea::placeholder{color:var(--text-muted)}.search-btn{position:absolute;right:12px;bottom:12px;background:var(--accent-gradient);color:#fff;width:40px;height:40px;border-radius:50%;display:flex;align-items:center;justify-content:center;transition:opacity .15s}.search-btn:disabled{opacity:.4;cursor:not-allowed}.search-btn svg{width:18px;height:18px}.brief-container{flex:1 1}.brief-loading{display:flex;flex-direction:column;align-items:center;gap:1rem;padding:3rem;color:var(--text-secondary)}.spinner{width:36px;height:36px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(1turn)}}.loading-steps{display:flex;flex-direction:column;gap:8px;font-size:.9rem}.loading-step{display:flex;align-items:center;gap:8px}.loading-step.done{color:var(--green)}.loading-step.active{color:var(--accent-light)}.loading-step.pending{color:var(--text-muted)}.brief{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden}.brief-header{padding:20px 24px;border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:space-between}.brief-header h2{font-size:1.1rem;font-weight:600}.brief-actions{display:flex;gap:8px}.brief-action-btn{display:flex;align-items:center;gap:6px;background:var(--bg-tertiary);color:var(--text-secondary);font-size:.85rem;padding:8px 14px;border-radius:var(--radius-sm);border:1px solid var(--border);transition:all .15s}.brief-action-btn:hover{border-color:var(--accent);color:var(--text)}.brief-action-btn.sent{border-color:var(--green);color:var(--green)}.brief-body{padding:24px}.brief-section{margin-bottom:24px}.brief-section:last-child{margin-bottom:0}.brief-section h3{font-size:.85rem;font-weight:600;text-transform:uppercase;letter-spacing:.05em;color:var(--accent-light);margin-bottom:12px}.brief-section li,.brief-section p{font-size:.95rem;line-height:1.7;color:var(--text-secondary)}.brief-section ol,.brief-section ul{padding-left:1.5rem}.brief-section li{margin-bottom:6px}.brief-section strong{color:var(--text)}.sources-grid{display:flex;flex-direction:column;gap:10px}.source-card{display:flex;gap:12px;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-sm);padding:14px;transition:border-color .15s}.source-card:hover{border-color:var(--border-light)}.source-num{flex-shrink:0;width:24px;height:24px;background:var(--accent-glow);color:var(--accent-light);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:.75rem;font-weight:600}.source-info{flex:1 1;min-width:0}.source-title{font-size:.9rem;font-weight:500;margin-bottom:4px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.source-meta{font-size:.8rem;color:var(--text-muted)}.source-tag{display:inline-block;font-size:.7rem;font-weight:600;text-transform:uppercase;padding:2px 8px;border-radius:4px;margin-right:8px}.source-tag.paper{background:rgba(124,92,255,.15);color:var(--accent-light)}.source-tag.article{background:rgba(96,165,250,.15);color:var(--blue)}.source-tag.video{background:rgba(251,146,60,.15);color:var(--orange)}.source-tag.blog{background:rgba(74,222,128,.15);color:var(--green)}.diagram-container{background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-sm);padding:20px;overflow-x:auto;display:flex;justify-content:center}.diagram-container svg{max-width:100%;height:auto}.chat-panel{display:flex;flex-direction:column;background:var(--bg-secondary)}.chat-header{padding:16px 20px;border-bottom:1px solid var(--border);font-weight:600;font-size:.95rem}.chat-messages{flex:1 1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:12px}.chat-empty{flex:1 1;display:flex;align-items:center;justify-content:center;color:var(--text-muted);text-align:center;padding:2rem}.chat-empty,.chat-msg{font-size:.9rem;line-height:1.6}.chat-msg{max-width:90%;padding:12px 16px;border-radius:var(--radius-sm)}.chat-msg.user{align-self:flex-end;background:var(--accent);color:#fff;border-bottom-right-radius:4px}.chat-msg.assistant{align-self:flex-start;background:var(--bg-tertiary);border:1px solid var(--border);color:var(--text-secondary);border-bottom-left-radius:4px}.chat-msg.assistant p{margin-bottom:8px}.chat-msg.assistant p:last-child{margin-bottom:0}.chat-msg.assistant strong{color:var(--text)}.chat-msg.assistant code{background:var(--bg-card);padding:2px 6px;border-radius:4px;font-family:var(--font-mono);font-size:.85em}.chat-typing{align-self:flex-start;padding:12px 16px;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-sm);display:flex;gap:4px}.chat-typing span{width:6px;height:6px;background:var(--text-muted);border-radius:50%;animation:bounce 1.4s infinite}.chat-typing span:nth-child(2){animation-delay:.2s}.chat-typing span:nth-child(3){animation-delay:.4s}@keyframes bounce{0%,80%,to{transform:translateY(0)}40%{transform:translateY(-6px)}}.chat-input-area{padding:16px;border-top:1px solid var(--border)}.chat-input-wrap{display:flex;gap:8px}.chat-input-wrap input{flex:1 1;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text);font-size:.9rem;padding:12px 16px;transition:border-color .2s}.chat-input-wrap input:focus{border-color:var(--accent)}.chat-input-wrap input::placeholder{color:var(--text-muted)}.chat-send-btn{background:var(--accent-gradient);color:#fff;padding:12px 16px;border-radius:var(--radius-sm);font-size:.9rem;font-weight:500;transition:opacity .15s}.chat-send-btn:disabled{opacity:.4;cursor:not-allowed}.cached-badge{display:inline-flex;align-items:center;gap:4px;background:rgba(74,222,128,.1);color:var(--green);font-size:.75rem;font-weight:600;padding:4px 10px;border-radius:20px;margin-left:12px}@media (max-width:900px){.dashboard{grid-template-columns:1fr}.chat-panel{height:50vh;border-top:1px solid var(--border)}.features{grid-template-columns:1fr}}