:root{--bg:#f4f7f8;--panel:#fff;--sidebar:#e9eef1;--text:#172026;--muted:#667783;--line:#d8e0e5;--hover:#dfe8ec;--assistant:#fff;--user:#e5f0f2;--accent:#0e6475;--accent-strong:#0a3f4c;--steel:#42515a;--warning:#b7791f;--danger-bg:#fff1f1;--danger:#9f2323;--message-column:760px}*{box-sizing:border-box}body,html{height:100%;overflow:hidden}body{background:var(--bg);color:var(--text);font-family:ui-sans-serif,-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Microsoft YaHei,sans-serif;margin:0}button,textarea{font:inherit}button{cursor:pointer}.chat-app,.chat-page{height:100vh;overflow:hidden}.chat-app{display:grid;grid-template-columns:280px minmax(0,1fr)}.chat-sidebar{background:var(--sidebar);border-right:1px solid var(--line);display:flex;flex-direction:column;gap:14px;height:100vh;overflow:hidden;padding:14px}.sidebar-brand{align-items:center;display:flex;gap:8px;justify-content:center;min-height:72px;padding:4px 6px}.brand-logo{background:#fff;border:1px solid var(--line);display:block;flex:0 0 auto;height:57px;overflow:hidden;position:relative;width:76px}.brand-logo img{background:#fff;height:100%;object-fit:cover;object-position:center;transform:scale(1.32);width:100%}.brand-name{align-items:center;display:grid;flex:0 0 auto;grid-gap:3px;gap:3px;justify-items:center;min-width:0;text-align:center}.brand-name strong{color:var(--accent-strong);font-size:18px;font-weight:800;line-height:1.2}.brand-name small{color:var(--muted);font-size:12px;font-weight:700;line-height:1.2}.icon-button,.menu-button,.new-chat-button,.send-button,.tool-button{align-items:center;border:0;border-radius:8px;display:inline-flex;justify-content:center}.new-chat-button{background:#fff;border:1px solid var(--line);color:var(--text);gap:8px;min-height:42px;padding:0 12px}.history-item:hover,.icon-button:hover,.menu-button:hover,.new-chat-button:hover,.tool-button:hover{background:var(--hover)}.history-search{align-items:center;background:#fff;border:1px solid var(--line);border-radius:8px;color:var(--muted);display:flex;gap:8px;min-height:40px;padding:0 10px}.history-search input{background:transparent;border:0;color:var(--text);min-width:0;outline:none;width:100%}.history-list{border-top:1px solid var(--line);display:flex;flex:1 1;flex-direction:column;gap:4px;min-height:120px;overflow-y:auto;padding-top:12px}.sidebar-label{color:var(--muted);font-size:12px;padding:0 8px 6px}.history-item{align-items:flex-start;background:transparent;border:0;border-radius:8px;color:var(--text);display:grid;grid-gap:4px;gap:4px;justify-items:start;min-height:54px;padding:9px 8px;text-align:left;width:100%}.history-item.active{background:#fff;box-shadow:inset 3px 0 0 var(--accent)}.history-item span{font-size:14px;max-width:100%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.empty-history,.history-item small{color:var(--muted);font-size:12px}.empty-history{margin:8px}.sidebar-section{border-top:1px solid var(--line);display:grid;grid-gap:6px;gap:6px;margin-top:6px;padding-top:16px}.sidebar-section span{color:var(--muted);font-size:12px;padding:0 8px}.sidebar-section p{border-radius:8px;color:#3f464d;font-size:14px;margin:0;padding:10px 8px}.chat-main{display:grid;grid-template-rows:auto minmax(0,1fr) auto;height:100vh;min-width:0;overflow:hidden}.chat-topbar{align-items:center;background:rgba(244,247,248,.96);border-bottom:1px solid var(--line);display:flex;gap:12px;justify-content:space-between;min-height:60px;padding:10px 18px;position:-webkit-sticky;position:sticky;top:0;z-index:2}.chat-topbar div{display:grid;flex:1 1;grid-gap:2px;gap:2px}.chat-topbar strong{color:var(--accent-strong);font-size:15px}.chat-topbar span{color:var(--muted);font-size:12px}.capability-grid{align-self:start;display:grid;grid-gap:12px;gap:12px;grid-template-columns:repeat(2,minmax(0,1fr));justify-self:center;margin:0 auto 20px;max-width:var(--message-column);padding:0;position:relative;width:100%;z-index:1}.capability-grid button{align-content:start;background:#fff;border:1px solid rgba(202,218,225,.92);border-radius:8px;box-shadow:0 14px 34px rgba(32,48,56,.08);color:var(--text);display:grid;grid-gap:12px;gap:12px;grid-template-columns:40px minmax(0,1fr) 20px;min-height:104px;padding:16px;text-align:left;transition:background .16s ease,border-color .16s ease,box-shadow .16s ease,transform .16s ease}.capability-grid button:hover{background:#fbfdfe;border-color:#9fc2cb;box-shadow:0 18px 36px rgba(14,100,117,.16);transform:translateY(-2px)}.capability-grid button>svg:first-child{background:#e5f0f2;border:1px solid #c7dde3;border-radius:8px;color:var(--accent);justify-self:center;padding:8px;height:40px;width:40px}.capability-grid span{display:grid;align-content:start;grid-gap:6px;gap:6px;min-width:0}.capability-grid strong{color:var(--accent-strong);font-size:15px;line-height:1.25}.capability-grid small{color:var(--muted);font-size:13px;line-height:1.5;white-space:normal}.capability-arrow{align-self:start;color:#8aa0aa;justify-self:end;margin-top:9px}.icon-button,.menu-button,.tool-button{background:transparent;color:var(--text);flex:0 0 auto;height:40px;width:40px}.menu-button{display:none}.message-list{display:flex;flex-direction:column;gap:0;min-height:0;overflow-y:auto;padding:22px 18px 24px}.message{display:grid;grid-gap:14px;gap:14px;justify-content:center;padding:18px 0;width:100%}.message,.message.user{grid-template-columns:34px minmax(0,var(--message-column)) 34px}.avatar{align-items:center;background:var(--steel);border-radius:50%;color:#fff;display:flex;font-size:12px;font-weight:700;height:30px;justify-content:center;margin-top:3px;width:30px}.message.user .avatar{background:var(--accent);grid-column:3;grid-row:1}.message.user .message-content{grid-column:2;grid-row:1;justify-self:end;max-width:100%;width:-moz-fit-content;width:fit-content}.message-content{background:var(--assistant);border:1px solid var(--line);border-radius:14px;grid-column:2;padding:14px 16px;word-break:break-word}.message.user .message-content{background:var(--user);border-color:#c2d9df}.markdown-body{line-height:1.75}.markdown-body>:first-child{margin-top:0}.markdown-body>:last-child{margin-bottom:0}.markdown-body blockquote,.markdown-body ol,.markdown-body p,.markdown-body pre,.markdown-body table,.markdown-body ul{margin:0 0 12px}.markdown-body ol,.markdown-body ul{padding-left:22px}.markdown-body li+li{margin-top:4px}.markdown-body code{background:#f1f5f9;border-radius:5px;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:.92em;padding:2px 5px}.markdown-body pre{background:#111827;border-radius:10px;color:#f8fafc;overflow-x:auto;padding:12px}.markdown-body pre code{background:transparent;color:inherit;padding:0}.markdown-body blockquote{border-left:3px solid #cbd5e1;color:var(--muted);padding-left:12px}.markdown-body a{color:var(--accent)}.reasoning-box{background:#f7fafb;border:1px solid #d9e6ea;border-radius:10px;color:#475569;margin-bottom:12px;padding:10px 12px}.reasoning-box summary{cursor:pointer;font-size:13px;font-weight:700;margin-bottom:8px}.loading-line{align-items:center;display:inline-flex;gap:8px}.spin{animation:spin .9s linear infinite}@keyframes spin{to{transform:rotate(1turn)}}.composer-wrap{background:linear-gradient(180deg,hsla(240,7%,97%,0),var(--bg) 18%);padding:16px 18px 18px}.attachment-row,.composer,.composer-note,.error-line,.follow-up-row{margin-left:auto;margin-right:auto;max-width:820px}.follow-up-row{display:flex;flex-wrap:wrap;gap:8px;justify-content:flex-start;margin-bottom:10px}.follow-up-row button{background:#fff;border:1px solid var(--line);border-radius:999px;color:var(--steel);font-size:13px;line-height:1.45;max-width:100%;padding:8px 12px;text-align:left}.follow-up-row button:hover{background:var(--hover);border-color:#bfd1d8;color:var(--accent-strong)}.attachment-row{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:10px}.attachment-pill{align-items:center;background:#fff;border:1px solid var(--line);border-radius:8px;display:flex;gap:8px;max-width:260px;min-height:38px;padding:6px 8px}.attachment-pill img{border-radius:5px;height:24px;object-fit:cover;width:24px}.attachment-pill span{font-size:13px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.attachment-pill button{background:transparent;border:0;color:var(--muted);font-size:20px;line-height:1;padding:0 3px}.error-line{background:var(--danger-bg);border:1px solid #f0caca;border-radius:8px;color:var(--danger);margin-bottom:10px;padding:10px 12px}.composer{align-items:flex-end;background:#fff;border:1px solid #d1d5db;border-radius:18px;box-shadow:0 14px 40px rgba(15,23,42,.08);display:grid;grid-gap:6px;gap:6px;grid-template-columns:40px 40px minmax(0,1fr) 40px;padding:8px}.composer textarea{background:transparent;border:0;line-height:1.55;max-height:180px;min-height:40px;outline:none;padding:9px 6px;resize:none}.send-button{background:var(--accent-strong);color:#fff;height:40px;width:40px}.send-button:disabled{background:#d1d5db;color:#fff;cursor:not-allowed}.composer-note{color:var(--muted);font-size:12px;margin-bottom:0;margin-top:8px;text-align:center}@media (max-width:820px){.chat-app{grid-template-columns:1fr}.chat-sidebar{display:none}.menu-button{display:inline-flex}.message-list{padding-left:12px;padding-right:12px}.capability-grid{display:flex;gap:10px;margin:0 auto 18px;overflow-x:auto;overscroll-behavior-x:contain;padding:0 12px 4px;width:calc(100% - 24px)}.capability-grid button{flex:0 0 248px}.message,.message.user{grid-template-columns:30px minmax(0,1fr) 30px}}@media (max-width:560px){.chat-topbar{padding-left:12px;padding-right:12px}.composer-wrap{padding:12px}.composer{grid-template-columns:38px 38px minmax(0,1fr) 38px;border-radius:16px;padding:7px}.capability-grid{gap:8px;margin:0 auto 16px;padding:0 10px 4px;width:calc(100% - 20px)}.capability-grid button{flex-basis:228px;grid-template-columns:36px minmax(0,1fr) 18px;min-height:118px;padding:14px}.capability-grid button>svg:first-child{height:36px;padding:7px;width:36px}.send-button,.tool-button{height:38px;width:38px}}