:root{
  --brand:#5D2E89;
  --brand-light:rgba(93,46,137,.08);
  --brand-border:rgba(93,46,137,.18);
  --bg:#f4f3f8;
  --card:#ffffff;
  --line:#e5e7eb;
  --text:#111827;
  --muted:rgba(17,24,39,.55);
  --shadow:0 2px 16px rgba(93,46,137,.07);
  --r:20px;
}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font:15px/1.45 system-ui,-apple-system,Segoe UI,Roboto,Arial;color:var(--text);background:var(--bg)}

.shell{max-width:1180px;margin:0 auto;padding:14px}

/* ── Header ── */
.shell__top{
  background:linear-gradient(135deg,#f5f0fc 0%,#ede5f8 100%);
  border:1px solid var(--brand-border);
  border-radius:var(--r);
  padding:18px 22px;
  margin-bottom:12px;
}

.shell__brand{
  display:flex;
  align-items:center;
  gap:12px;
  margin-bottom:14px;
}

.logo{
  width:40px;height:40px;
  border-radius:11px;
  background:var(--brand);
  display:flex;align-items:center;justify-content:center;
  font-weight:800;font-size:13px;color:#fff;
  border:none;
  flex-shrink:0;
}

.h1{
  font-size:18px;font-weight:800;
  letter-spacing:-.2px;
  color:#3C1F6A;
}

.muted{
  font-size:12.5px;
  color:var(--text);
  margin-top:2px;
}

/* ── Záložky kanceláří ── */
.tabs{display:flex;flex-wrap:wrap;gap:7px}

.tab{
  appearance:none;
  background:rgba(255,255,255,.7);
  border:1px solid var(--brand-border);
  border-radius:999px;
  padding:6px 14px;
  font-size:13px;font-weight:600;
  color:var(--text);
  cursor:pointer;
  transition:background .15s, color .15s;
}

.tab:hover{
  background:rgba(255,255,255,.95);
}

.tab.is-active{
  background:var(--brand);
  border-color:transparent;
  color:#fff;
}

.tab:active{transform:translateY(1px)}

/* ── iframe ── */
.frame{
  background:var(--card);
  border:1px solid rgba(17,24,39,.07);
  border-radius:18px;
  box-shadow:var(--shadow);
  overflow:hidden;
}

.frame iframe{width:100%;height:82vh;border:0;display:block;background:#fff}

/* ── Mobil ── */
@media(max-width:600px){
  .shell__top{padding:14px 16px}
  .h1{font-size:16px}
  .tab{padding:5px 12px;font-size:12px}
}