:root{
  --bg:#070D18;--panel:#0C1526;--card:#111D33;--line:#1C2A44;--text:#E7EEF8;--dim:#8C9DB8;
  --accent:#4CC9F0;--accent2:#7B8CFF;--glow:rgba(76,201,240,.45);--err:#FF7A7A;--radius:18px;
  font-synthesis:none;
}

*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{background:var(--bg);color:var(--text);font:16px/1.55 ui-sans-serif,system-ui,"Segoe UI",Roboto,sans-serif;-webkit-font-smoothing:antialiased}
button,input,textarea,select{font:inherit;color:inherit}
button{cursor:pointer;border:0;background:none}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:10px}
.dim{color:var(--dim)} .small{font-size:13px} .err{color:var(--err);min-height:1.4em}
code{font:13px ui-monospace,Menlo,Consolas,monospace;background:var(--card);padding:1px 6px;border-radius:6px}
[hidden]{display:none!important}

/* the glowing core */
.core{position:relative;border-radius:50%;display:grid;place-items:center;flex:none}
.core span{width:42%;height:42%;border-radius:50%;background:radial-gradient(circle at 40% 35%,#fff,var(--accent) 45%,var(--accent2));box-shadow:0 0 18px var(--glow),0 0 42px var(--glow)}
.core::before{content:"";position:absolute;inset:0;border-radius:50%;border:2px solid var(--accent);opacity:.75;box-shadow:0 0 22px var(--glow),inset 0 0 18px var(--glow)}
.core.small{width:26px;height:26px}.core.small::before{border-width:1.5px}
.core.big{width:92px;height:92px}
.core.huge{width:132px;height:132px;animation:breathe 4.5s ease-in-out infinite}
.core.busy span{animation:pulse 1s ease-in-out infinite}
@keyframes breathe{50%{transform:scale(1.04)}}
@keyframes pulse{50%{transform:scale(.8);opacity:.75}}
@media (prefers-reduced-motion: reduce){.core.huge,.core.busy span{animation:none}}

/* sign in */
.login{min-height:100%;display:grid;place-items:center;padding:24px}
.login-card{width:min(400px,100%);text-align:center;display:flex;flex-direction:column;align-items:center;gap:12px}
.login h1{letter-spacing:.32em;font-size:22px;margin:8px 0 0;font-weight:700}
.login form{display:flex;flex-direction:column;gap:10px;width:100%;margin-top:8px}
.login input{text-align:center;letter-spacing:.12em;font-size:18px}
input,textarea,select{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:12px 14px;width:100%}
input:focus,textarea:focus,select:focus{outline:none;border-color:var(--accent)}
.primary{background:var(--accent);color:#04121C;font-weight:650;border-radius:12px;padding:12px 18px}
.ghost{border:1px solid var(--line);border-radius:12px;padding:10px 14px;background:var(--card)}
.link{color:var(--dim);padding:8px 6px;border-radius:8px}.link:hover{color:var(--text)}
a.link{text-decoration:none}

/* layout */
.app{display:grid;grid-template-columns:288px 1fr;height:100%}
.side{background:var(--panel);border-right:1px solid var(--line);display:flex;flex-direction:column;padding:14px 12px;min-height:0}
.side-top{display:flex;align-items:center;justify-content:space-between;padding:4px 6px 12px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;letter-spacing:.28em;font-size:14px}
.new{display:flex;align-items:center;gap:8px;border:1px solid var(--line);background:var(--card);border-radius:14px;padding:10px 14px;font-weight:600}
.new span{color:var(--accent);font-size:20px;line-height:1}
.new:hover{border-color:var(--accent)}
.search{margin:10px 0 6px;padding:9px 12px;font-size:14px}
.chats{flex:1;overflow:auto;margin:4px -4px;padding:0 4px}
.chats h4{font-size:12px;color:var(--dim);font-weight:600;margin:14px 8px 4px;text-transform:uppercase;letter-spacing:.06em}
.chat-item{display:block;width:100%;text-align:left;padding:9px 10px;border-radius:10px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-size:14.5px}
.chat-item:hover{background:var(--card)}
.chat-item.on{background:var(--card);box-shadow:inset 3px 0 0 var(--accent)}
.side-bottom{display:flex;justify-content:space-between;border-top:1px solid var(--line);padding-top:8px;margin-top:6px}
.scrim{display:none}
.main{display:flex;flex-direction:column;min-width:0;height:100%;position:relative}
.bar{display:flex;align-items:center;gap:8px;padding:12px 18px;border-bottom:1px solid var(--line);min-height:56px}
.title{flex:1;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.icon{width:40px;height:40px;border-radius:12px;display:grid;place-items:center;font-size:18px;color:var(--dim)}
.icon:hover{background:var(--card);color:var(--text)}
.only-mobile{display:none}

.empty{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;padding:24px;text-align:center}
.empty h2{margin:14px 0 0;font-size:26px;font-weight:650}
.chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-top:10px;max-width:620px}
.chip{border:1px solid var(--line);background:var(--card);border-radius:999px;padding:8px 14px;font-size:14px}
.chip:hover{border-color:var(--accent)}

.thread{flex:1;overflow:auto;padding:24px 18px 8px;display:none}
.thread.on{display:block}
.msg{max-width:760px;margin:0 auto 18px;display:flex;gap:12px}
.msg.user{justify-content:flex-end}
.msg.user .bubble{background:var(--card);border:1px solid var(--line);border-radius:18px 18px 4px 18px;padding:10px 14px;max-width:80%;white-space:pre-wrap;word-wrap:break-word}
.msg.bot .core{margin-top:3px}
.msg.bot .body{flex:1;min-width:0}
.msg.bot .text p{margin:0 0 10px}.msg.bot .text p:last-child{margin:0}
.msg.bot .text ul,.msg.bot .text ol{margin:0 0 10px;padding-left:22px}
.msg.bot .text a{color:var(--accent)}
.meta{font-size:12px;color:var(--dim);margin-top:6px;display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.src{display:inline-flex;gap:6px;align-items:center;border:1px solid var(--line);border-radius:999px;padding:2px 10px;color:var(--dim);text-decoration:none;font-size:12px}
.src:hover{border-color:var(--accent);color:var(--text)}
.thinking .text{color:var(--dim)}

.composer{padding:10px 18px calc(14px + env(safe-area-inset-bottom))}
.box{max-width:760px;margin:0 auto;display:flex;align-items:flex-end;gap:6px;background:var(--panel);border:1px solid var(--line);border-radius:24px;padding:6px 6px 6px 16px;box-shadow:0 8px 30px rgba(0,0,0,.18)}
.box:focus-within{border-color:var(--accent)}
.box textarea{border:0;background:none;padding:9px 0;resize:none;max-height:200px;line-height:1.45}
.box textarea:focus{outline:none}
.box svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.send{width:40px;height:40px;border-radius:50%;background:var(--accent);color:#04121C;display:grid;place-items:center}
.send:disabled{opacity:.4;cursor:default}
.mic.rec{color:#fff;background:var(--err);animation:pulse 1.2s infinite}
.hint{max-width:760px;margin:6px auto 0;font-size:12px;min-height:1em;text-align:center}

.sheet{position:fixed;inset:0;background:rgba(2,6,14,.6);display:grid;place-items:center;padding:16px;z-index:20}
.sheet-card{background:var(--panel);border:1px solid var(--line);border-radius:22px;width:min(520px,100%);max-height:90vh;overflow:auto;padding:18px 20px}
.sheet-head{display:flex;justify-content:space-between;align-items:center}
.sheet-head h2{margin:0;font-size:20px}
.group{border-top:1px solid var(--line);padding:14px 0;display:flex;flex-direction:column;gap:10px}
.group:first-of-type{border-top:0}
.group h3{margin:0;font-size:13px;text-transform:uppercase;letter-spacing:.08em;color:var(--dim)}
.group p{margin:0}
label{display:flex;flex-direction:column;gap:6px;font-size:14px}
label.row{flex-direction:row;align-items:center;gap:10px}
label.row input{width:auto}
.sheet-foot{display:flex;justify-content:space-between;align-items:center;padding-top:12px;border-top:1px solid var(--line)}
.toast{position:fixed;left:50%;bottom:96px;transform:translateX(-50%) translateY(20px);background:var(--card);border:1px solid var(--line);padding:10px 16px;border-radius:12px;opacity:0;transition:.2s;pointer-events:none;z-index:30;max-width:90vw}
.toast.on{opacity:1;transform:translateX(-50%)}

@media (max-width:820px){
  .app{grid-template-columns:1fr}
  .side{position:fixed;inset:0 auto 0 0;width:min(86vw,320px);z-index:10;transform:translateX(-100%);transition:transform .2s}
  .side.open{transform:none}
  .scrim{display:block;position:fixed;inset:0;background:rgba(2,6,14,.5);z-index:9;opacity:0;pointer-events:none;transition:.2s}
  .side.open + .scrim{opacity:1;pointer-events:auto}
  .only-mobile{display:grid}
  .bar{padding:8px 10px}
  .thread{padding:16px 12px 6px}
  .composer{padding:8px 10px calc(10px + env(safe-area-inset-bottom))}
}

.stack{display:flex;flex-direction:column;gap:10px;width:100%}
.wide{width:100%}
.login .link{margin-top:2px}
.row2{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:8px 0;border-bottom:1px solid var(--line)}
.row2:last-child{border-bottom:0}
.row2 .what{min-width:0}
.row2 .what b{display:block;font-weight:600;font-size:14px}
.row2 .what span{font-size:12.5px;color:var(--dim);display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.mini{border:1px solid var(--line);background:var(--card);border-radius:10px;padding:6px 10px;font-size:13px;flex:none}
.mini.danger{color:var(--err)}
.switch{display:flex;flex-direction:row;align-items:flex-start;gap:10px;font-size:14px}
.switch input{width:auto;margin-top:4px}
.bad{color:var(--err)}
details summary{cursor:pointer;color:var(--dim);font-size:13px}
#huSteps{margin:0 0 14px;padding-left:22px}#huSteps li{margin:6px 0}