/* 复用现有原生侧栏：本页锚定在 .session-sidebar 右侧（left/top 由 JS 写入） */
    .lah-overlay{
      position:fixed;inset:0;z-index:100000;background:#FBFBFB;overflow-y:auto;
      display:flex;flex-direction:column;
      font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;
      color:rgba(0,0,0,0.82);-webkit-font-smoothing:antialiased;animation:lah-fade .2s ease;
    }
    @keyframes lah-fade{from{opacity:0}to{opacity:1}}
    /* 顶部栏：返回 + 历史 */
    .lah-topbar{
      flex:0 0 auto;display:flex;align-items:center;justify-content:space-between;
      height:52px;padding:0 18px;
    }
    .lah-icon-btn{
      display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;
      border:none;background:transparent;border-radius:8px;color:rgba(0,0,0,0.64);cursor:pointer;
      transition:background .15s ease;
    }
    .lah-icon-btn:hover{background:rgba(0,0,0,0.05);}
    .lah-icon-btn svg{width:18px;height:18px;}
    /* 中央内容 */
    .lah-center{
      flex:1 1 auto;display:flex;flex-direction:column;align-items:center;
      padding:0 24px;margin-top:calc(20vh - 40px);
    }
    .lah-avatar{
      width:100px;height:100px;border-radius:28px;flex:0 0 auto;margin-bottom:14px;
      background:linear-gradient(135deg,#5b9dff,#2f6bff);
      display:flex;align-items:center;justify-content:center;
      box-shadow:0 10px 26px rgba(47,107,255,.28);
    }
    .lah-avatar svg{width:56px;height:56px;stroke:#fff;fill:none;}
    .lah-greeting{
      margin:0 0 22px;font-size:32px;line-height:48px;font-weight:700;
      font-family:"Songti SC","STSong","SimSun",serif;color:rgba(0,0,0,0.82);text-align:center;
    }
    /* Composer 输入框 */
    .lah-composer{
      width:100%;max-width:710px;background:#fff;border:1px solid rgba(0,0,0,0.06);
      border-radius:28px;box-shadow:0 6px 12px rgba(0,0,0,0.03);
      padding:16px 10px 10px;box-sizing:border-box;
    }
    .lah-input{
      display:block;width:100%;border:none;outline:none;resize:none;background:transparent;
      padding:0 10px;min-height:26px;max-height:160px;font:inherit;font-size:16px;line-height:24px;
      color:rgba(0,0,0,0.82);box-sizing:border-box;overflow-y:auto;
    }
    .lah-input::placeholder{color:rgba(0,0,0,0.28);}
    .lah-toolbar{display:flex;align-items:center;gap:8px;margin-top:14px;padding:0 2px;}
    .lah-tool-btn{
      display:inline-flex;align-items:center;justify-content:center;width:36px;height:36px;
      border:none;border-radius:28px;background:transparent;color:rgba(0,0,0,0.64);cursor:pointer;
      transition:background .15s ease;
    }
    .lah-tool-btn:hover{background:rgba(0,0,0,0.05);}
    .lah-tool-btn svg{width:20px;height:20px;}
    .lah-tool-btn--at{font-size:18px;font-weight:500;}
    .lah-agent-chip{
      display:inline-flex;align-items:center;gap:4px;height:28px;padding:3px 8px;border-radius:8px;
      background:rgba(109,128,255,0.08);color:#495DFF;font-size:14px;line-height:22px;cursor:pointer;
      user-select:none;
    }
    .lah-agent-chip svg{width:12px;height:12px;}
    .lah-send{
      margin-left:auto;display:inline-flex;align-items:center;justify-content:center;
      width:36px;height:36px;border:none;border-radius:50%;background:#495DFF;color:#fff;cursor:pointer;
      transition:background .15s ease,opacity .15s ease;
    }
    .lah-send:hover{background:#3546e0;}
    .lah-send svg{width:18px;height:18px;}
    /* 快捷指令 chips（输入框下方） */
    .lah-chips{
      display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-top:16px;
      width:100%;max-width:710px;
    }
    .lah-chip{
      display:inline-flex;align-items:center;gap:7px;padding:12px 16px;
      border:1px solid rgba(0,0,0,0.09);border-radius:20px;background:#fff;
      font:inherit;font-size:16px;line-height:24px;color:rgba(0,0,0,0.82);cursor:pointer;
      transition:border-color .15s ease,background .15s ease,box-shadow .15s ease;
    }
    .lah-chip:hover{border-color:rgba(0,0,0,0.16);box-shadow:0 4px 12px rgba(15,23,42,.06);}
    .lah-chip__ic{display:inline-flex;align-items:center;color:rgba(0,0,0,0.5);flex:0 0 auto;}
    .lah-chip__ic svg{width:18px;height:18px;}
    /* 底部提示 */
    .lah-footer{
      flex:0 0 auto;text-align:center;padding:18px 0 22px;
      font-size:12px;line-height:18px;color:rgba(0,0,0,0.28);
    }