:root {
  --bg: #0d1117;
  --bg-2: #131a24;
  --panel: #161d29;
  --panel-2: #1c2533;
  --border: #263141;
  --text: #e6edf3;
  --muted: #93a1b3;
  --accent: #7c5cff;
  --accent-2: #4dd0c4;
  --user: #243044;
  --radius: 16px;
  --maxw: 820px;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: radial-gradient(1200px 600px at 70% -10%, #1b2333 0%, var(--bg) 55%);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  flex-direction: column;
  line-height: 1.55;
}

/* ---- top bar ---- */
.topbar {
  position: sticky; top: 0; z-index: 5;
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 18px;
  background: rgba(13,17,23,.82);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 38px; height: 38px; border-radius: 11px;
  display: grid; place-items: center;
  font-weight: 800; font-size: 19px; color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 4px 14px rgba(124,92,255,.35);
}
.brand-text { display: flex; flex-direction: column; }
.brand-text strong { font-size: 15px; }
.brand-text span { font-size: 12px; color: var(--muted); }
.ghost-btn {
  background: transparent; color: var(--muted);
  border: 1px solid var(--border); border-radius: 10px;
  padding: 8px 12px; font-size: 13px; cursor: pointer; transition: .15s;
}
.ghost-btn:hover { color: var(--text); border-color: var(--accent); }

/* ---- chat area ---- */
.chat {
  flex: 1; overflow-y: auto;
  padding: 26px 18px 40px;
}
.chat > *, .composer-inner, .disclaimer { max-width: var(--maxw); margin-left: auto; margin-right: auto; }

.welcome { text-align: center; padding: 8vh 8px 4vh; }
.welcome h1 { font-size: 30px; margin: 0 0 10px; font-weight: 800; }
.welcome h1 span { background: linear-gradient(135deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.welcome p { color: var(--muted); max-width: 560px; margin: 0 auto 26px; }
.suggestions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; max-width: 620px; margin: 0 auto; }
.chip {
  text-align: left; background: var(--panel); color: var(--text);
  border: 1px solid var(--border); border-radius: 12px;
  padding: 12px 14px; font-size: 14px; cursor: pointer; transition: .15s;
}
.chip:hover { border-color: var(--accent); transform: translateY(-1px); background: var(--panel-2); }

/* ---- messages ---- */
.msg { display: flex; gap: 12px; margin: 18px 0; }
.msg .avatar {
  flex: 0 0 32px; width: 32px; height: 32px; border-radius: 9px;
  display: grid; place-items: center; font-size: 14px; font-weight: 700;
}
.msg.user { flex-direction: row-reverse; }
.msg.user .avatar { background: var(--user); color: var(--text); }
.msg.bot .avatar { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; }
.bubble {
  max-width: 84%; padding: 13px 16px; border-radius: var(--radius);
  border: 1px solid var(--border); background: var(--panel);
}
.msg.user .bubble { background: var(--user); border-color: #2f3d52; border-bottom-right-radius: 6px; }
.msg.bot .bubble { border-bottom-left-radius: 6px; }

/* ---- agent activity panel ---- */
.activity {
  margin-bottom: 10px; border: 1px solid var(--border);
  border-radius: 12px; background: var(--bg-2); overflow: hidden;
}
.activity summary {
  cursor: pointer; list-style: none; padding: 9px 12px;
  font-size: 13px; color: var(--muted); display: flex; align-items: center; gap: 8px;
}
.activity summary::-webkit-details-marker { display: none; }
.activity[open] summary { border-bottom: 1px solid var(--border); }
.activity .body { padding: 10px 12px; font-size: 13px; color: var(--muted); }
.step { display: flex; gap: 8px; padding: 3px 0; align-items: flex-start; }
.step .dot { color: var(--accent-2); }
.queries { display: flex; flex-wrap: wrap; gap: 6px; margin: 4px 0 8px; }
.qpill { background: var(--panel-2); border: 1px solid var(--border); border-radius: 999px; padding: 3px 10px; font-size: 12px; }

.spinner {
  width: 13px; height: 13px; border-radius: 50%;
  border: 2px solid var(--border); border-top-color: var(--accent);
  display: inline-block; animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.live { display: flex; align-items: center; gap: 9px; font-size: 13px; color: var(--muted); padding: 2px 0; }

/* ---- markdown content ---- */
.md > *:first-child { margin-top: 0; }
.md > *:last-child { margin-bottom: 0; }
.md h1, .md h2, .md h3 { line-height: 1.3; margin: 16px 0 8px; }
.md h1 { font-size: 20px; } .md h2 { font-size: 18px; } .md h3 { font-size: 16px; }
.md p { margin: 9px 0; }
.md ul, .md ol { margin: 9px 0; padding-left: 22px; }
.md li { margin: 4px 0; }
.md a { color: var(--accent-2); }
.md code { background: var(--bg); border: 1px solid var(--border); border-radius: 5px; padding: 1px 5px; font-size: 13px; }
.md pre { background: var(--bg); border: 1px solid var(--border); border-radius: 10px; padding: 12px; overflow-x: auto; }
.md pre code { border: 0; padding: 0; }
.md strong { color: #fff; }
.cite {
  display: inline-block; min-width: 18px; text-align: center;
  background: var(--panel-2); border: 1px solid var(--border); color: var(--accent-2);
  border-radius: 6px; font-size: 11px; padding: 0 5px; margin: 0 1px; text-decoration: none;
  vertical-align: text-top;
}
.cite:hover { border-color: var(--accent-2); }
.cursor::after { content: "▍"; color: var(--accent); animation: blink 1s steps(2) infinite; }
@keyframes blink { 0%,50% { opacity: 1; } 50.01%,100% { opacity: 0; } }

/* ---- sources ---- */
.sources { margin-top: 12px; border-top: 1px dashed var(--border); padding-top: 10px; }
.sources h4 { margin: 0 0 7px; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.source { display: flex; gap: 8px; align-items: baseline; font-size: 13px; padding: 2px 0; }
.source .n { color: var(--accent-2); font-weight: 700; flex: 0 0 auto; }
.source a { color: var(--text); text-decoration: none; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.source a:hover { color: var(--accent-2); }

/* ---- composer ---- */
.composer {
  position: sticky; bottom: 0;
  padding: 12px 18px 14px;
  background: linear-gradient(transparent, var(--bg) 22%);
}
.composer-inner {
  display: flex; gap: 8px; align-items: flex-end;
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 16px; padding: 8px 8px 8px 14px;
}
.composer-inner:focus-within { border-color: var(--accent); }
#input {
  flex: 1; resize: none; border: 0; outline: 0; background: transparent;
  color: var(--text); font: inherit; max-height: 180px; padding: 6px 0;
}
#send {
  flex: 0 0 auto; width: 40px; height: 40px; border-radius: 11px; border: 0; cursor: pointer;
  background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff;
  display: grid; place-items: center; transition: .15s;
}
#send:disabled { opacity: .45; cursor: default; }
.disclaimer { color: var(--muted); font-size: 11.5px; text-align: center; margin: 8px auto 0; }
.error-note { color: #ff8a8a; }

@media (max-width: 600px) {
  .suggestions { grid-template-columns: 1fr; }
  .bubble { max-width: 90%; }
  .welcome { padding-top: 5vh; }
}