:root{
  /* Light, brand — matches the desktop NoTrack Coder app */
  --bg:#ffffff; --bg2:#f6f5fb; --panel:#ffffff; --panel2:#f3f1fa; --line:#e7e5ef; --line2:#dedbec;
  --text:#14121c; --dim:#5b5570; --mute:#8a8398;
  --accent:#7c3aed; --accent-soft:#f1ebfe; --accent-line:#d9ccfb; --accent2:#7c3aed; --err:#dc2645;
  --radius:14px; --font:-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;
  --shadow:0 10px 30px rgba(20,18,28,.08);
}
:root[data-theme="dark"]{
  --bg:#0e0b16; --bg2:#141020; --panel:#171225; --panel2:#1e1830; --line:#2a2340; --line2:#352c52;
  --text:#ece9f5; --dim:#b7b0cc; --mute:#7d7595; --accent-soft:#241a3a; --accent-line:#3a2d63;
  --shadow:0 10px 30px rgba(0,0,0,.4);
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font);font-size:15px;line-height:1.55}
.hidden{display:none!important}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;background:var(--accent);color:#fff;border:0;border-radius:11px;padding:10px 16px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none;text-align:center}
.btn:hover{background:#6d28d9}

/* login gate */
.gate{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;padding:20px;background:var(--bg2)}
.gate-card{background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:36px 32px;max-width:360px;width:100%;text-align:center;box-shadow:var(--shadow)}
.brand{display:inline-flex;align-items:center;gap:11px;margin-bottom:12px;text-decoration:none;color:var(--text)}
.brand-mark{display:block;flex:none;border-radius:30%;box-shadow:0 4px 16px -5px rgba(118,75,162,.5)}
.brand-name{font-family:system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;font-weight:700;font-size:18px;letter-spacing:-.03em;color:var(--text)}
.brand .brand-c{color:#6d28d9}

/* Reply preloader — 1:1 with the desktop app: weaving brand-gradient dots + "Thinking… Ns",
   replaced by the streamed reply as soon as it arrives. */
.sc-dots{display:inline-flex;gap:5px;align-items:center;vertical-align:middle}
.sc-dots i{width:7px;height:7px;border-radius:50%;background:linear-gradient(135deg,#667eea,#764ba2);animation:scweave 1.2s ease-in-out infinite}
.sc-dots i:nth-child(2){animation-delay:.18s}
.sc-dots i:nth-child(3){animation-delay:.36s}
@keyframes scweave{0%,100%{transform:scale(.55);opacity:.35}40%{transform:scale(1);opacity:1}}
.bubble .tt{color:var(--dim);font-size:13px;margin-left:8px}
.msg-assistant .bubble.thinking{background:transparent;border:0;padding-left:0;box-shadow:none}
.brand .logo{width:34px;height:34px;border-radius:9px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;display:grid;place-items:center;font-weight:800;font-size:18px;box-shadow:0 4px 16px -5px rgba(118,75,162,.6);border:1px solid rgba(255,255,255,.25)}
.brand span{color:var(--accent)}
.gate-card p{color:var(--dim);margin:0 0 20px}

/* app shell */
.app{display:flex;height:100vh;height:100dvh;background:var(--bg)}
.sidebar{width:272px;flex:0 0 272px;min-height:0;background:var(--bg2);border-right:1px solid var(--line);display:flex;flex-direction:column;padding:12px;gap:10px}
.side-tabs{display:flex;gap:4px;background:var(--panel2);border:1px solid var(--line);border-radius:12px;padding:4px}
.side-tabs button{flex:1;background:transparent;border:0;border-radius:9px;padding:8px;font:inherit;font-weight:600;color:var(--dim);cursor:pointer}
.side-tabs button.on{background:var(--panel);color:var(--text);box-shadow:var(--shadow)}
.side-tabs button.tab-soon{opacity:.55;cursor:not-allowed;display:inline-flex;align-items:center;justify-content:center;gap:6px}
.side-tabs button.tab-soon .soon{font-size:9px;font-weight:800;text-transform:uppercase;letter-spacing:.05em;color:#fff;background:var(--mute);border-radius:999px;padding:1px 6px}
.side-cap{font-size:11.5px;color:var(--mute);text-align:center;padding:2px 4px 4px;letter-spacing:.01em}
.btn-new{width:100%}
.conv-list{flex:1;min-height:0;overflow-y:auto;-webkit-overflow-scrolling:touch;overscroll-behavior:contain;display:flex;flex-direction:column;gap:1px;margin-top:2px}
.conv{display:flex;align-items:center;gap:2px;border:0;background:transparent;border-radius:9px;color:var(--dim);padding-left:4px}
.conv:hover{background:var(--panel2);color:var(--text)}
.conv.active{background:color-mix(in srgb,var(--accent) 15%,var(--panel));color:var(--text)}
.conv.active .conv-title{font-weight:600}
.conv.active .conv-ico{opacity:1;border-color:var(--accent)}
.conv-ico{flex:0 0 auto;width:15px;height:15px;border:1.6px solid currentColor;border-radius:999px;opacity:.5}
.conv-title{flex:1;min-width:0;text-align:left;background:transparent;border:0;color:inherit;padding:9px 6px 9px 9px;cursor:pointer;font:inherit;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.conv-del{flex:0 0 auto;width:24px;height:24px;margin-right:4px;border:0;background:transparent;color:var(--mute);border-radius:7px;cursor:pointer;font-size:17px;line-height:1;opacity:0;transition:opacity .12s,background .12s}
.conv:hover .conv-del{opacity:1}
.conv-del:hover{background:color-mix(in srgb,var(--err) 18%,transparent);color:var(--err)}
.sidebar-foot{border-top:1px solid var(--line);padding-top:10px;display:flex;align-items:center;justify-content:space-between}
.tier{font-size:10px;font-weight:800;color:#fff;background:var(--accent);padding:2px 7px;border-radius:999px;text-transform:uppercase;letter-spacing:.06em;flex:0 0 auto}
.user{display:flex;align-items:center;gap:7px;min-width:0}
.user-av{width:26px;height:26px;border-radius:999px;background:transparent;color:var(--dim);display:grid;place-items:center;font-size:14px;flex:0 0 auto;overflow:hidden}
.user-av img{border-radius:999px}
.user-av img{width:100%;height:100%;object-fit:cover}
.user-name{font-size:13.5px;font-weight:600;color:var(--text);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.back-site{flex:0 0 auto;width:32px;height:32px;border-radius:9px;border:1px solid var(--line);background:var(--panel);color:var(--dim);display:grid;place-items:center;text-decoration:none;font-size:15px}
.back-site:hover{color:var(--accent);border-color:var(--accent-line)}

.main{flex:1;display:flex;flex-direction:column;min-width:0;min-height:0;position:relative}
.topbar{height:52px;flex:0 0 52px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:12px;padding:0 16px}
.topbar .brand{font-size:16px;margin:0;text-decoration:none;color:var(--text);cursor:pointer}
.topbar .brand:hover{opacity:.85}
.theme-btn{margin-left:auto;display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;border:1px solid var(--line);border-radius:8px;background:var(--panel);color:var(--dim);cursor:pointer;padding:0;transition:background .12s,color .12s,border-color .12s}
.theme-btn:hover{background:var(--panel2);color:var(--text)}
.theme-btn svg{width:15px;height:15px;display:block}
.messages{flex:1;min-height:0;overflow-y:auto;-webkit-overflow-scrolling:touch;overscroll-behavior:contain;padding:24px 16px;display:flex;flex-direction:column;gap:14px;max-width:820px;width:100%;margin:0 auto}
.welcome{margin:auto;text-align:center;color:var(--dim);max-width:460px}
.welcome .logo-lg{width:56px;height:56px;border-radius:16px;background:var(--accent);color:#fff;display:grid;place-items:center;font-weight:800;font-size:28px;margin:0 auto 18px}
.welcome h1{color:var(--text);font-size:26px;font-weight:800;letter-spacing:-.02em;margin:0 0 8px}
.pc-steps{text-align:left;max-width:420px;margin:14px auto 18px;padding-left:20px;display:flex;flex-direction:column;gap:9px;color:var(--text)}
.pc-steps li{font-size:14.5px;line-height:1.5}
.pc-dl{margin:0 auto}
.pc-note{font-size:12.5px;color:var(--mute);margin-top:14px}
.msg{display:flex}
.msg-user{justify-content:flex-end}
.bubble{white-space:pre-wrap;word-wrap:break-word;padding:11px 14px;border-radius:14px;max-width:80%}
.msg-user .bubble{background:var(--accent);color:#fff;border-bottom-right-radius:4px}
.msg-assistant .bubble{background:var(--panel2);border:1px solid var(--line);border-bottom-left-radius:4px}

.card{align-self:flex-start;max-width:80%;background:var(--panel2);border:1px solid var(--line);border-radius:12px;padding:12px 14px}
.card-err{border-color:color-mix(in srgb,var(--err) 45%,var(--line))}
.card-title{font-weight:600}
.card-text{color:var(--dim);margin-top:4px;font-size:14px}
.card-upgrade{align-self:flex-start;background:transparent;border:0;padding:0}

.composer{display:flex;gap:10px;align-items:flex-end;padding:14px 16px;border-top:1px solid var(--line);max-width:820px;width:100%;margin:0 auto}
#input{flex:1;resize:none;background:var(--panel);border:1px solid var(--line2);color:var(--text);border-radius:12px;padding:12px 14px;font:inherit;max-height:200px;box-shadow:var(--shadow)}
#input:focus{outline:none;border-color:var(--accent)}
.btn-send{align-self:stretch}

/* Mobile burger (opens the chats sidebar) — hidden on desktop. */
.burger{display:none;align-items:center;justify-content:center;width:34px;height:34px;border:1px solid var(--line);border-radius:9px;background:var(--panel);color:var(--text);cursor:pointer;padding:0;flex:0 0 auto}
.burger svg{width:20px;height:20px;display:block}
.side-backdrop{display:none}

@media (max-width:720px){
  .burger{display:inline-flex}
  .sidebar{position:fixed;z-index:30;left:0;top:0;bottom:0;transform:translateX(-100%);transition:transform .2s;box-shadow:var(--shadow)}
  .sidebar.open{transform:none}
  .sidebar.open ~ .side-backdrop{display:block;position:fixed;inset:0;z-index:20;background:rgba(10,8,16,.4)}
  .messages,.composer{padding-left:12px;padding-right:12px}
}