:root {
  --ink: #1a1a2e;
  --muted: #5a5a72;
  --accent: #0b5563;
  --accent-light: #e8f4f6;
  --warn-bg: #fff4e5;
  --warn-edge: #d97706;
  --rule: #e2e2ec;
  --user-bg: #0b5563;
  --bot-bg: #f5f7f8;
  --bg: #fbfbfd;
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink); background: var(--bg); line-height: 1.5;
}
.hidden { display: none !important; }
.badge {
  background: var(--warn-edge); color: #fff; font-size: .6em; font-weight: 700;
  padding: .2em .6em; border-radius: 999px; vertical-align: middle; letter-spacing: .04em;
}
.badge.small { font-size: .55rem; }

#send-btn, #reset-btn {
  font: inherit; border: none; border-radius: 8px; cursor: pointer;
}

/* --- App shell --- */
.app { display: flex; flex-direction: column; height: 100vh; max-width: 860px; margin: 0 auto; }
.topbar {
  display: flex; align-items: center; gap: 1rem; padding: .7rem 1rem;
  border-bottom: 1px solid var(--rule); background: #fff;
}
.brand { font-weight: 700; font-size: 1.1rem; }
.stack-meta { color: var(--muted); font-size: .72rem; flex: 1; }
.ghost { background: transparent; border: 1px solid var(--rule); padding: .35rem .8rem; color: var(--muted); }
.caveat-banner {
  background: var(--warn-bg); color: #7a4b07; font-size: .76rem;
  padding: .45rem 1rem; border-bottom: 1px solid #f0dcc0;
}

/* --- Chat --- */
.chat { flex: 1; overflow-y: auto; padding: 1.2rem 1rem; }
.empty-state { text-align: center; color: var(--muted); margin-top: 3rem; }
.empty-state h2 { color: var(--ink); }
.suggestions { display: flex; flex-wrap: wrap; gap: .5rem; justify-content: center; margin-top: 1.2rem; }
.chip {
  background: var(--accent-light); color: var(--accent); border: 1px solid #cfe6ea;
  border-radius: 999px; padding: .4rem .9rem; font-size: .82rem; cursor: pointer;
}
.msg { margin: 0 0 1.1rem; display: flex; }
.msg.user { justify-content: flex-end; }
.bubble { max-width: 88%; padding: .7rem 1rem; border-radius: 12px; }
.msg.user .bubble { background: var(--user-bg); color: #fff; border-bottom-right-radius: 3px; }
.msg.bot .bubble { background: var(--bot-bg); border-bottom-left-radius: 3px; width: 100%; max-width: 100%; }
.bubble :first-child { margin-top: 0; }
.bubble :last-child { margin-bottom: 0; }
.bubble ul, .bubble ol { padding-left: 1.3rem; }
.bubble code { background: #e8e8ef; padding: .1em .3em; border-radius: 3px; font-size: .9em; }

/* --- Citations --- */
.context-box {
  background: #fff; border: 1px solid var(--rule); border-radius: 10px;
  margin: 0 0 .5rem; font-size: .82rem; overflow: hidden;
}
.context-head {
  padding: .45rem .8rem; cursor: pointer; color: var(--accent); font-weight: 600;
  display: flex; justify-content: space-between; align-items: center; user-select: none;
}
.context-body { padding: 0 .8rem .6rem; display: none; }
.context-box.open .context-body { display: block; }
.cit { padding: .5rem 0; border-top: 1px dashed var(--rule); }
.cit-meta { color: var(--muted); font-size: .74rem; }
.cit-src { font-weight: 600; color: var(--ink); }
a.cit-link { color: var(--accent); text-decoration: none; }
a.cit-link:hover { text-decoration: underline; }

/* --- Feedback --- */
.feedback {
  margin-top: .6rem; padding: .6rem .8rem; border: 1px dashed var(--rule);
  border-radius: 10px; font-size: .82rem; background: #fff;
}
.fb-row { display: flex; flex-wrap: wrap; align-items: center; gap: .5rem; margin-bottom: .5rem; }
.fb-label { color: var(--muted); }
.stars { display: inline-flex; gap: .15rem; cursor: pointer; }
.star { font-size: 1.15rem; color: #d3d3dd; }
.star.on { color: #e8a13a; }
.tag {
  border: 1px solid var(--rule); border-radius: 999px; padding: .2rem .6rem;
  cursor: pointer; background: #fff; font-size: .76rem;
}
.tag.on { background: var(--accent); color: #fff; border-color: var(--accent); }
.fb-comment { width: 100%; border: 1px solid var(--rule); border-radius: 6px; padding: .4rem; font: inherit; font-size: .82rem; resize: vertical; }
.fb-submit { background: var(--accent); color: #fff; border: none; border-radius: 6px; padding: .35rem .9rem; cursor: pointer; font: inherit; font-size: .8rem; }
.fb-done { color: var(--accent); font-weight: 600; }

/* --- Composer --- */
.composer { display: flex; gap: .6rem; padding: .8rem 1rem; border-top: 1px solid var(--rule); background: #fff; }
#input { flex: 1; resize: none; border: 1px solid var(--rule); border-radius: 10px; padding: .6rem .8rem; font: inherit; max-height: 160px; }
#send-btn { background: var(--accent); color: #fff; padding: 0 1.3rem; font-weight: 600; }
#send-btn:disabled { background: #b8c4c7; cursor: not-allowed; }
/* Retrieval (RAG) toggle — device parity with the on-device "Search" toggle. */
.retrieval-toggle { font: inherit; border: 1px solid var(--accent); border-radius: 8px;
  cursor: pointer; padding: 0 .8rem; font-size: .8rem; font-weight: 600; white-space: nowrap; }
.retrieval-toggle.on { background: var(--accent); color: #fff; }
.retrieval-toggle.off { background: transparent; color: var(--muted); border-color: var(--rule); }
.cursor-blink::after { content: "▋"; animation: blink 1s steps(2) infinite; color: var(--muted); }
@keyframes blink { 0%,50% { opacity: 1 } 50.01%,100% { opacity: 0 } }

/* --- About modal --- */
.muted { color: var(--muted); }
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,.45);
  display: flex; align-items: center; justify-content: center; padding: 1rem; z-index: 50; }
.modal-overlay.hidden { display: none; }
.modal { background: #fff; border-radius: 14px; width: min(720px, 100%);
  max-height: 86vh; display: flex; flex-direction: column; overflow: hidden; }
.modal-head { display: flex; align-items: center; justify-content: space-between;
  padding: .9rem 1.1rem; border-bottom: 1px solid var(--rule); }
.modal-head h2 { font-size: 1.05rem; margin: 0; }
.modal-body { padding: 1.1rem; overflow-y: auto; }
.about-grid { display: grid; grid-template-columns: max-content 1fr; gap: .5rem 1rem; margin: 0 0 1rem; }
.about-grid dt { font-weight: 700; color: var(--accent); }
.about-grid dd { margin: 0; }
.about-prompt-head { display: flex; align-items: center; justify-content: space-between;
  margin-bottom: .4rem; font-weight: 700; }
.raw-prompt { background: var(--bot-bg); border: 1px solid var(--rule); border-radius: 8px;
  padding: .8rem; font-size: .8rem; line-height: 1.5; white-space: pre-wrap; word-break: break-word;
  max-height: 40vh; overflow-y: auto; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }