:root{--primary-color:#00a862;--primary-light:#e9faf2;--bg-color:#f7f9fa;--sidebar-bg:#fff;--text-main:#1f2329;--text-secondary:#8f959e;--text-tertiary:#b0b5bd;--border-color:#e5e7eb;--hover-bg:#f0f2f5;--white:#fff;--shadow-sm:0 1px 3px #0000000a;--shadow-md:0 4px 20px #0000000f;--shadow-focus:0 4px 20px #00a8621f;--radius-sm:8px;--radius-md:12px;--radius-lg:16px;--radius-pill:20px}*{box-sizing:border-box;margin:0;padding:0}body,html{background-color:var(--bg-color);height:100%;color:var(--text-main);margin:0;padding:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,PingFang SC,Microsoft YaHei,sans-serif;overflow:hidden}.app-container{height:100vh;display:flex}.sidebar{background-color:var(--sidebar-bg);border-right:1px solid var(--border-color);flex-direction:column;width:280px;padding:16px;display:flex}.logo-area{-webkit-user-select:none;user-select:none;border-bottom:1px solid var(--border-color);align-items:center;margin-bottom:16px;padding:16px 8px 20px;display:flex}.logo-title{letter-spacing:3px;color:var(--primary-color);font-size:28px;font-weight:800;line-height:1}.new-chat-btn{background-color:var(--bg-color);border:1px solid var(--border-color);border-radius:var(--radius-md);color:var(--text-main);cursor:pointer;outline:none;align-items:center;gap:8px;width:100%;margin-bottom:20px;padding:12px 14px;font-family:inherit;font-size:14px;font-weight:500;transition:all .2s;display:flex}.new-chat-btn:hover{background-color:var(--primary-light);border-color:var(--primary-color);color:var(--primary-color);box-shadow:0 2px 8px #00a86214}.new-chat-icon{font-size:18px;font-weight:300;line-height:1}.history-list{flex:1;overflow-y:auto}.history-title{color:var(--text-secondary);margin:0 8px 12px;font-size:12px;font-weight:600}.empty-history{text-align:center;border-radius:var(--radius-md);border:1px dashed var(--border-color);background:var(--white);flex-direction:column;justify-content:center;align-items:center;gap:10px;margin:0 4px;padding:32px 16px;display:flex}.empty-icon{background:var(--bg-color);width:40px;height:40px;color:var(--text-tertiary);border-radius:10px;justify-content:center;align-items:center;display:flex}.empty-icon svg{width:20px;height:20px}.empty-title{color:var(--text-secondary);font-size:14px;font-weight:500}.empty-desc{color:var(--text-tertiary);font-size:12px;line-height:1.5}.history-item{color:var(--text-main);cursor:pointer;border-radius:var(--radius-sm);white-space:nowrap;text-overflow:ellipsis;padding:10px 12px;font-size:14px;transition:background-color .2s;overflow:hidden}.history-item:hover{background-color:var(--hover-bg)}.user-area{border-top:1px solid var(--border-color);cursor:pointer;border-radius:var(--radius-sm);justify-content:space-between;align-items:center;margin-top:10px;padding:12px 8px 8px;transition:background-color .2s;display:flex}.user-area:hover{background-color:var(--hover-bg)}.user-info{align-items:center;gap:10px;display:flex}.user-avatar{background-color:var(--border-color);width:32px;height:32px;color:var(--text-secondary);border-radius:50%;justify-content:center;align-items:center;font-size:14px;font-weight:500;display:flex}.user-text{flex-direction:column;gap:2px;display:flex}.user-name{color:var(--text-main);font-size:14px;font-weight:500}.user-hint{color:var(--text-tertiary);font-size:11px}.settings-icon{width:28px;height:28px;color:var(--text-secondary);border-radius:8px;justify-content:center;align-items:center;transition:all .2s;display:flex}.settings-icon:hover{background:var(--hover-bg);color:var(--text-main)}.settings-icon svg{width:16px;height:16px}.main-content{flex-direction:column;flex:1;display:flex;position:relative;overflow:hidden}.top-bar{justify-content:flex-end;height:60px;padding:10px 20px;display:flex}.greeting-area{flex-direction:column;flex:1;justify-content:center;align-items:center;gap:32px;padding:0 20%;display:flex}.hero{text-align:center;flex-direction:column;align-items:center;gap:12px;display:flex}.greeting-title{color:var(--text-main);font-size:30px;font-weight:600;line-height:1.2}.hero-sub{color:var(--text-secondary);max-width:420px;font-size:15px;line-height:1.5}.suggestion-buttons{flex-wrap:wrap;justify-content:center;gap:10px;max-width:560px;display:flex}.suggestion-btn{background-color:var(--white);border:1px solid var(--border-color);border-radius:var(--radius-pill);cursor:pointer;color:var(--text-secondary);box-shadow:var(--shadow-sm);align-items:center;gap:6px;padding:8px 16px;font-family:inherit;font-size:13px;transition:all .2s;display:flex}.suggestion-btn:hover{border-color:var(--primary-color);color:var(--primary-color);background:var(--primary-light);box-shadow:0 4px 12px #0000000f}.suggestion-btn svg{opacity:.6;width:14px;height:14px}.chat-history{overflow-anchor:none;flex-direction:column;flex:1;gap:28px;padding:20px 20% 44px;display:flex;overflow:hidden auto}.msg-row{width:100%;display:flex}.msg-row.user{justify-content:flex-end}.msg-row.ai{justify-content:flex-start}.msg-bubble{border-radius:var(--radius-md);word-break:break-word;white-space:pre-wrap;padding:12px 16px;font-size:15px;line-height:1.6}.msg-row.user .msg-bubble{background:var(--primary-color);color:#fff;border-bottom-right-radius:4px}.msg-row.ai .msg-bubble{background:var(--white);color:var(--text-main);border:1px solid var(--border-color);box-shadow:var(--shadow-sm);border-bottom-left-radius:4px}.input-area-wrapper{padding:20px 20% 32px}.input-container{background-color:var(--white);border-radius:var(--radius-lg);box-shadow:var(--shadow-md);border:1px solid var(--border-color);padding:14px 16px;transition:box-shadow .3s,border-color .3s;position:relative}.input-container:focus-within{border-color:var(--primary-color);box-shadow:var(--shadow-focus)}textarea{resize:none;width:100%;min-height:24px;max-height:150px;color:var(--text-main);background:0 0;border:none;outline:none;font-family:inherit;font-size:16px;line-height:1.5}.input-actions{justify-content:space-between;align-items:center;margin-top:12px;display:flex}.upload-btn{border:1px solid var(--border-color);width:32px;height:32px;color:var(--text-secondary);cursor:pointer;background-color:#0000;border-radius:50%;justify-content:center;align-items:center;transition:all .2s;display:flex}.upload-btn:hover{background-color:var(--bg-color);color:var(--primary-color);border-color:var(--primary-color)}.upload-btn svg{width:16px;height:16px}.send-btn{background-color:var(--primary-color);color:#fff;cursor:pointer;border:none;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:36px;height:36px;transition:opacity .2s,transform .1s;display:flex;box-shadow:0 2px 8px #00a8624d}.send-btn:active{transform:scale(.95)}.send-btn:disabled{box-shadow:none;cursor:not-allowed;background-color:#ccc}.send-btn svg{width:16px;height:16px}.input-hint{color:var(--text-tertiary);text-align:center;flex:1;font-size:12px}.disclaimer{text-align:center;color:var(--text-secondary);margin-top:16px;font-size:12px}.disclaimer a{color:inherit;text-decoration:none}.disclaimer a:hover{color:var(--primary-color)}.user-area-wrapper{position:relative}.user-popup{border:1px solid var(--border-color);opacity:0;visibility:hidden;pointer-events:none;z-index:100;background:#fff;border-radius:12px;padding:6px;transition:opacity .15s,transform .15s,visibility .15s;position:absolute;bottom:calc(100% + 8px);left:0;right:0;transform:translateY(6px);box-shadow:0 8px 28px #0000001f}.user-popup.show{opacity:1;visibility:visible;pointer-events:auto;transform:translateY(0)}.user-popup-item{color:var(--text-main);cursor:pointer;-webkit-user-select:none;user-select:none;border-radius:8px;align-items:center;gap:10px;padding:9px 12px;font-size:13px;transition:background .15s,color .15s;display:flex}.user-popup-item:hover{background:var(--hover-bg)}.user-popup-item.danger{color:#dc2626}.user-popup-item.danger:hover{background:#fee}.user-popup-item svg{flex-shrink:0!important;width:14px!important;height:14px!important;display:block!important}.user-popup-divider{background:var(--border-color);height:1px;margin:4px 8px}.delete-modal-overlay{z-index:2000;background:#0006;justify-content:center;align-items:center;display:flex;position:fixed;inset:0}.delete-modal{background:#fff;border-radius:14px;width:380px;padding:24px;box-shadow:0 20px 60px #0003}.delete-modal-title{color:var(--text-main);margin:0 0 8px;font-size:17px;font-weight:600}.delete-modal-desc{color:var(--text-secondary);margin:0 0 20px;font-size:14px;line-height:1.5}.delete-modal-actions{justify-content:flex-end;gap:10px;display:flex}.delete-modal-btn{cursor:pointer;border:1px solid #0000;border-radius:8px;padding:9px 18px;font-family:inherit;font-size:14px;font-weight:500;transition:all .15s}.delete-modal-btn.cancel{border-color:var(--border-color);color:var(--text-main);background:#fff}.delete-modal-btn.cancel:hover{background:var(--hover-bg)}.delete-modal-btn.confirm{color:#fff;background:#dc2626}.delete-modal-btn.confirm:hover{background:#b91c1c}.msg-bubble-wrap{max-width:80%;display:inline-block;position:relative}.msg-bubble-wrap .msg-bubble{max-width:100%}.msg-menu-container{z-index:10;margin-top:4px;display:flex;position:absolute;top:100%}.msg-row.user .msg-menu-container{right:0}.msg-row.ai .msg-menu-container{left:0}.msg-menu-trigger{color:#b0b5bd;cursor:pointer;background:0 0;border:none;border-radius:6px;justify-content:center;align-items:center;width:22px;height:22px;padding:0;font-family:inherit;transition:background .15s,color .15s;display:flex}.msg-menu-trigger svg{width:14px;height:14px}.msg-menu-trigger:hover{background:var(--hover-bg);color:var(--text-main)}.msg-menu{border:1px solid var(--border-color);z-index:50;background:#fff;border-radius:10px;min-width:130px;padding:4px;animation:.12s ease-out msgMenuIn;position:absolute;top:calc(100% + 4px);box-shadow:0 8px 24px #0000001f}.msg-row.user .msg-menu{right:0}.msg-row.ai .msg-menu{left:0}@keyframes msgMenuIn{0%{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:translateY(0)}}.msg-menu-item{width:100%;color:var(--text-main);cursor:pointer;text-align:left;background:0 0;border:none;border-radius:6px;align-items:center;gap:10px;padding:8px 10px;font-family:inherit;font-size:13px;transition:background .15s,color .15s;display:flex}.msg-menu-item:hover{background:var(--hover-bg)}.msg-menu-item.danger{color:#dc2626}.msg-menu-item.danger:hover{background:#fee}.msg-menu-item svg{flex-shrink:0;width:14px;height:14px}