:root{
  --bg:#f6f7f9; --panel:#ffffff; --panel-2:#f1f3f6; --line:#e3e6ec;
  --text:#14161a; --muted:#6b7280; --brand:#4f46e5; --brand-ink:#ffffff;
  --mine:#4f46e5; --mine-ink:#fff; --theirs:#ffffff; --theirs-ink:#14161a;
  --danger:#dc2626; --radius:14px;
  --safe-t:env(safe-area-inset-top,0px); --safe-b:env(safe-area-inset-bottom,0px);
}
@media (prefers-color-scheme:dark){
  :root{
    --bg:#0d0f13; --panel:#15181e; --panel-2:#1b1f27; --line:#272c36;
    --text:#e8eaef; --muted:#9aa3b2; --theirs:#1f242e; --theirs-ink:#e8eaef;
  }
}
*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{
  font:15px/1.5 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg); color:var(--text); overscroll-behavior:none;
  -webkit-font-smoothing:antialiased;
}
.hidden{display:none !important}
[hidden]{display:none !important}
.muted{color:var(--muted)}
.small{font-size:12px}
button{font:inherit}

/* ---------- accesso ---------- */
.auth{min-height:100dvh;display:grid;place-items:center;padding:24px 16px}
.auth-card{width:100%;max-width:380px;background:var(--panel);border:1px solid var(--line);
  border-radius:20px;padding:28px 24px 22px;box-shadow:0 10px 40px rgba(0,0,0,.06)}
.logo{color:var(--brand);display:flex;justify-content:center;margin-bottom:10px}
.auth h1{margin:0 0 4px;font-size:22px;text-align:center}
.auth .muted{margin:0 0 20px;text-align:center;font-size:13px}
.field{display:block;margin-bottom:14px}
.field span{display:block;font-size:12px;font-weight:600;color:var(--muted);margin-bottom:5px}
input,textarea{
  width:100%;padding:11px 12px;border:1px solid var(--line);border-radius:10px;
  background:var(--panel-2);color:var(--text);font:inherit;outline:none
}
input:focus,textarea:focus{border-color:var(--brand);background:var(--panel)}
.btn{border:0;border-radius:10px;padding:11px 16px;font-weight:600;cursor:pointer;
  background:var(--panel-2);color:var(--text)}
.btn.primary{background:var(--brand);color:var(--brand-ink);width:100%}
.btn.primary:disabled{opacity:.6;cursor:progress}
.btn.small{padding:7px 12px;font-size:13px;background:var(--brand);color:#fff;white-space:nowrap}
.link{background:none;border:0;color:var(--brand);font-weight:600;cursor:pointer;padding:0}
.switch{text-align:center;font-size:13px;color:var(--muted);margin:16px 0 0}
.error{color:var(--danger);font-size:13px;margin:0 0 12px}

/* ---------- layout app ---------- */
.app{display:grid;grid-template-columns:320px 1fr;height:100dvh}
.sidebar{background:var(--panel);border-right:1px solid var(--line);display:flex;flex-direction:column;min-height:0}
.side-head{display:flex;align-items:center;gap:10px;padding:calc(12px + var(--safe-t)) 14px 12px;border-bottom:1px solid var(--line)}
.profile{display:flex;align-items:center;gap:10px;flex:1;min-width:0}
.me-text{min-width:0}
.me-text strong{display:block;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.me-text span{display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.avatar{width:38px;height:38px;border-radius:50%;display:grid;place-items:center;
  color:#fff;font-weight:700;font-size:15px;background:var(--brand);flex:none;text-transform:uppercase}
.icon-btn{background:none;border:0;color:var(--muted);cursor:pointer;padding:8px;border-radius:9px;display:grid;place-items:center}
.icon-btn:hover{background:var(--panel-2);color:var(--text)}

.banner{margin:10px;padding:11px 12px;background:var(--panel-2);border:1px solid var(--line);
  border-radius:12px;display:flex;gap:10px;align-items:center}
.banner strong{display:block;font-size:13px}
.banner p{margin:2px 0 0;font-size:12px;color:var(--muted)}

.status{display:flex;align-items:center;justify-content:space-between;gap:8px;
  margin:0 10px 4px;padding:6px 10px;font-size:12px;color:var(--muted);
  background:var(--panel-2);border-radius:9px}
.status b{font-weight:700}
.status b.ok{color:#16a34a}
.status b.ko{color:var(--danger)}

.chat-list{flex:1;overflow-y:auto;padding:6px 8px calc(10px + var(--safe-b))}
.section-label{font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;
  color:var(--muted);padding:12px 8px 6px}
.row{display:flex;align-items:center;gap:11px;width:100%;padding:9px 8px;border:0;border-radius:12px;
  background:none;color:var(--text);cursor:pointer;text-align:left}
.row:hover{background:var(--panel-2)}
.row.active{background:color-mix(in srgb,var(--brand) 14%,transparent)}
.row-text{flex:1;min-width:0}
.row-text strong{display:block;font-size:14px;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.row-text span{display:block;font-size:12px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.badge{background:var(--brand);color:#fff;font-size:11px;font-weight:700;min-width:20px;height:20px;
  border-radius:10px;display:grid;place-items:center;padding:0 6px;flex:none}
.dot{width:9px;height:9px;border-radius:50%;background:#22c55e;flex:none;box-shadow:0 0 0 2px var(--panel)}

/* ---------- conversazione ---------- */
.chat{display:flex;flex-direction:column;min-width:0;min-height:0;background:var(--bg)}
.chat-head{display:flex;align-items:center;gap:11px;padding:calc(11px + var(--safe-t)) 14px 11px;
  background:var(--panel);border-bottom:1px solid var(--line)}
.chat-title{min-width:0}
.chat-title strong{display:block;font-size:15px}
.only-mobile{display:none}
.messages{flex:1;overflow-y:auto;padding:16px 14px;display:flex;flex-direction:column;gap:3px}
.empty{margin:auto;color:var(--muted);text-align:center;font-size:14px}
.day{align-self:center;background:var(--panel-2);color:var(--muted);font-size:11px;font-weight:600;
  padding:4px 11px;border-radius:20px;margin:12px 0 6px}
.msg{max-width:min(78%,560px);width:fit-content;padding:7px 11px;border-radius:16px;
  overflow-wrap:anywhere}
.msg.them{align-self:flex-start;background:var(--theirs);color:var(--theirs-ink);
  border-bottom-left-radius:5px;border:1px solid var(--line)}
.msg.me{align-self:flex-end;background:var(--mine);color:var(--mine-ink);border-bottom-right-radius:5px}
.msg .who{display:block;font-size:11.5px;font-weight:700;margin-bottom:1px;opacity:.9}
.msg .text{white-space:pre-wrap}
.msg .time{font-size:10.5px;opacity:.6;margin-left:7px;white-space:nowrap}
.msg.group-cont{margin-top:-1px}

.composer{display:flex;gap:9px;align-items:flex-end;padding:10px 12px calc(10px + var(--safe-b));
  background:var(--panel);border-top:1px solid var(--line)}
.composer textarea{resize:none;max-height:140px;border-radius:20px;padding:10px 14px}
.send{width:42px;height:42px;flex:none;border:0;border-radius:50%;background:var(--brand);color:#fff;
  display:grid;place-items:center;cursor:pointer}
.send:disabled{opacity:.45}

.toast{position:fixed;left:50%;bottom:calc(22px + var(--safe-b));transform:translateX(-50%);
  background:#14161a;color:#fff;padding:11px 18px;border-radius:11px;font-size:13.5px;
  z-index:50;max-width:88vw;text-align:center;box-shadow:0 8px 30px rgba(0,0,0,.25)}

/* ---------- mobile ---------- */
@media (max-width:760px){
  .app{grid-template-columns:1fr}
  .sidebar{grid-column:1;grid-row:1}
  .chat{display:none}
  .app.show-chat .sidebar{display:none}
  .app.show-chat .chat{display:flex;grid-column:1;grid-row:1}
  .only-mobile{display:grid}
  .msg{max-width:84%}
}