/* RED20 PWA Shell v31 - only floating Back button, no page menu links */
:root{
  --red20-pwa-blue:#2563eb;
  --red20-pwa-blue2:#1d4ed8;
  --red20-pwa-card:rgba(15,23,42,.94);
  --red20-pwa-line:rgba(148,163,184,.30);
}
.red20-pwa-shell,.red20-pwa-shell *{box-sizing:border-box}
.red20-pwa-shell{position:fixed;right:14px;bottom:14px;z-index:2147482400;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Arial;display:flex;align-items:flex-end;gap:10px;pointer-events:none}
.red20-pwa-actions{display:flex;gap:8px;align-items:center;pointer-events:auto}
.red20-pwa-btn{border:1px solid var(--red20-pwa-line);background:linear-gradient(135deg,var(--red20-pwa-blue),var(--red20-pwa-blue2));color:#fff;border-radius:999px;min-height:42px;padding:9px 14px;font-size:13px;font-weight:950;box-shadow:0 14px 34px rgba(37,99,235,.26);cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;gap:7px;line-height:1;white-space:nowrap}
.red20-pwa-btn:hover{filter:brightness(1.06)}
.red20-pwa-btn:active{transform:scale(.98)}
.red20-pwa-btn.secondary{background:var(--red20-pwa-card);backdrop-filter:blur(14px);box-shadow:0 12px 32px rgba(0,0,0,.26)}
.red20-pwa-toast{position:fixed;left:12px;right:12px;bottom:72px;z-index:2147482600;display:flex;justify-content:center;pointer-events:none}.red20-pwa-toast>div{max-width:520px;border-radius:16px;background:rgba(15,23,42,.97);border:1px solid rgba(148,163,184,.28);color:#e5e7eb;padding:10px 13px;box-shadow:0 18px 50px rgba(0,0,0,.42);font-size:13px;font-weight:900;line-height:1.35}
@media(max-width:580px){.red20-pwa-shell{right:10px;bottom:10px}.red20-pwa-btn{min-height:40px;padding:8px 12px;font-size:12px}}
@media print{.red20-pwa-shell,.red20-pwa-toast{display:none!important}}