:root{
  --internal-bg:#f4f7fb;
  --internal-panel:#ffffff;
  --internal-text:#162033;
  --internal-muted:#66758a;
  --internal-line:#d8e0ea;
  --internal-primary:#155eef;
  --internal-primary-dark:#0f49c9;
  --internal-accent:#16a34a;
  --internal-warn:#f59e0b;
  --internal-shadow:0 20px 60px rgba(18,35,67,.10);
}
*{box-sizing:border-box}
body.internal-body{margin:0;font-family:"PingFang SC","Microsoft YaHei",sans-serif;background:
linear-gradient(180deg,#eef4ff 0%,#f4f7fb 180px,#f4f7fb 100%);color:var(--internal-text)}
.internal-shell{min-height:100vh}
.internal-header{padding:28px 24px 12px}
.internal-header .inner{max-width:1180px;margin:0 auto;background:linear-gradient(135deg,#0f1f3d 0%,#194d92 100%);color:#fff;border-radius:24px;padding:28px 32px;box-shadow:var(--internal-shadow)}
.btn-back-home{background:#eaf1ff;color:var(--internal-primary);border:1px solid #c7d7fb}
.btn-back-home:hover{background:#dbeafe}
.internal-header h1{margin:0 0 10px;font-size:2rem}
.internal-header p{margin:0;color:rgba(255,255,255,.78);line-height:1.7}
.internal-header .meta{margin-top:14px;display:flex;gap:10px;flex-wrap:wrap}
.internal-badge{display:inline-flex;align-items:center;gap:6px;padding:6px 12px;border-radius:999px;background:rgba(255,255,255,.14);font-size:.85rem}
.internal-main{max-width:1180px;margin:0 auto;padding:0 24px 56px}
.internal-login{max-width:440px;margin:-48px auto 0;background:var(--internal-panel);border:1px solid var(--internal-line);border-radius:22px;padding:28px;box-shadow:var(--internal-shadow)}
.internal-login h2{margin:0 0 8px;font-size:1.45rem}
.internal-login p{margin:0 0 20px;color:var(--internal-muted);line-height:1.65}
.form-row{display:flex;gap:12px;flex-wrap:wrap}
.form-field{margin-bottom:14px}
.form-field label{display:block;font-size:.92rem;font-weight:600;margin-bottom:8px}
.form-field input,.kb-toolbar input,.kb-toolbar textarea,.kb-toolbar select{width:100%;padding:12px 14px;border:1px solid var(--internal-line);border-radius:14px;background:#fff;color:var(--internal-text);font-size:1rem}
.form-field input:focus,.kb-toolbar input:focus,.kb-toolbar textarea:focus,.kb-toolbar select:focus{outline:none;border-color:var(--internal-primary);box-shadow:0 0 0 4px rgba(21,94,239,.12)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:none;border-radius:14px;padding:12px 18px;font-size:.96rem;font-weight:700;cursor:pointer;text-decoration:none;transition:.2s}
.btn-primary{background:var(--internal-primary);color:#fff}
.btn-primary:hover{background:var(--internal-primary-dark)}
.btn-secondary{background:#eaf1ff;color:var(--internal-primary)}
.btn-ghost{background:#fff;color:var(--internal-text);border:1px solid var(--internal-line)}
.login-error,.kb-error{min-height:20px;color:#dc2626;font-size:.92rem;margin-top:8px}
.internal-apps{display:none;padding-top:28px}
.section-heading{display:flex;align-items:end;justify-content:space-between;gap:16px;margin-bottom:18px}
.section-heading h2{margin:0;font-size:1.6rem}
.section-heading p{margin:6px 0 0;color:var(--internal-muted)}
.app-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}
.app-card{background:var(--internal-panel);border:1px solid var(--internal-line);border-radius:22px;padding:22px;box-shadow:var(--internal-shadow);display:flex;flex-direction:column;gap:14px}
.app-card.coming-soon{opacity:.84}
.app-top{display:flex;align-items:center;justify-content:space-between;gap:12px}
.app-icon{width:52px;height:52px;border-radius:16px;background:linear-gradient(135deg,#dbeafe,#eff6ff);display:flex;align-items:center;justify-content:center;color:var(--internal-primary);font-size:1.35rem}
.app-status{display:inline-flex;padding:5px 10px;border-radius:999px;font-size:.8rem;font-weight:700}
.app-status.live{background:#dcfce7;color:#166534}
.app-status.plan{background:#fef3c7;color:#92400e}
.app-card h3{margin:0;font-size:1.25rem}
.app-card p{margin:0;color:var(--internal-muted);line-height:1.7}
.app-features{margin:0;padding:0;list-style:none;display:grid;gap:8px}
.app-features li{color:#344256;font-size:.95rem}
.app-actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:auto}
.internal-topbar{display:none;align-items:center;justify-content:space-between;gap:12px;padding:22px 0 8px}
.internal-topbar-left{display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.internal-user{color:var(--internal-muted);font-size:.95rem}
.kb-layout{display:grid;grid-template-columns:minmax(0,1.8fr) minmax(320px,1fr);gap:18px;padding-top:24px}
.kb-panel{background:var(--internal-panel);border:1px solid var(--internal-line);border-radius:22px;box-shadow:var(--internal-shadow)}
.kb-panel .hd{padding:20px 22px 0}
.kb-panel .bd{padding:20px 22px 22px}
.kb-panel h2,.kb-panel h3{margin:0}
.kb-sub{margin:10px 0 0;color:var(--internal-muted);line-height:1.65}
.kb-toolbar{display:grid;gap:12px}
.kb-toolbar .inline{display:grid;grid-template-columns:1fr 160px 140px;gap:12px}
.kb-toolbar textarea{min-height:120px;resize:vertical}
.kb-chat{display:grid;gap:14px}
.kb-answer{background:#f7fafc;border:1px solid #e6edf6;border-radius:18px;padding:16px;min-height:180px;line-height:1.8;white-space:pre-wrap}
.kb-answer.empty{color:var(--internal-muted)}
.kb-sources{display:grid;gap:12px}
.source-card{border:1px solid var(--internal-line);border-radius:16px;padding:14px;background:#fff}
.source-card h4{margin:0 0 6px;font-size:1rem}
.source-meta{font-size:.84rem;color:var(--internal-muted);margin-bottom:8px}
.source-snippet{font-size:.93rem;color:#344256;line-height:1.7}
.kb-loading{display:none;color:var(--internal-primary);font-weight:700}
.kb-note{color:var(--internal-muted);font-size:.9rem}
.hidden{display:none!important}
@media (max-width: 960px){
  .app-grid,.kb-layout{grid-template-columns:1fr}
  .kb-toolbar .inline{grid-template-columns:1fr}
}
@media (max-width: 640px){
  .internal-header,.internal-main{padding-left:16px;padding-right:16px}
  .internal-header .inner,.internal-login,.app-card,.kb-panel{padding-left:18px;padding-right:18px}
  .internal-header h1{font-size:1.6rem}
  .internal-topbar{align-items:flex-start}
  .internal-topbar-left{align-items:flex-start}
  .btn-back-home{padding:10px 14px;font-size:.9rem}
}