:root {
  --bg: #0b0f1e;
  --surface: #12182e;
  --surface-2: #1a223d;
  --border: #2a3352;
  --text: #e8ecf4;
  --text-dim: #9aa3b8;
  --text-muted: #6b738a;
  --accent: #6e8bff;
  --green: #10b981;
  --gold: #f59e0b;
  --red: #ef4444;
  --cyan: #22d3ee;
  --purple: #7c3aed;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; height: 100%; background: var(--bg); color: var(--text); font-family: 'DM Sans', system-ui, sans-serif; font-size: 14px; }
.hidden { display: none !important; }

/* Login */
.login-screen { position: fixed; inset: 0; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #0b0f1e, #1a223d); z-index: 100; }
.login-card { width: 380px; padding: 36px; background: rgba(15,20,46,0.85); border: 1px solid var(--border); border-radius: 14px; }
.form-row { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }
.form-row label { font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-dim); font-weight: 600; }
input { background: rgba(0,0,0,0.25); color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 10px 12px; font-size: 14px; font-family: inherit; outline: none; transition: border-color .15s; }
input:focus { border-color: var(--accent); }
.btn-primary { background: var(--accent); color: white; border: none; border-radius: 8px; padding: 8px 18px; font-size: 13px; font-weight: 600; cursor: pointer; font-family: inherit; transition: filter .15s; }
.btn-primary:hover { filter: brightness(1.1); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-ghost { background: transparent; color: var(--text-dim); border: 1px solid var(--border); border-radius: 8px; padding: 6px 12px; font-size: 12px; cursor: pointer; font-family: inherit; transition: color .15s, border-color .15s; }
.btn-ghost:hover { color: var(--text); border-color: var(--accent); }
.login-error { color: var(--red); font-size: 12px; padding: 8px 12px; background: rgba(239,68,68,0.1); border: 1px solid rgba(239,68,68,0.3); border-radius: 8px; margin-bottom: 12px; }

/* Brand */
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark { width: 38px; height: 38px; background: var(--accent); color: white; border-radius: 8px; display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 18px; }
.brand-text .brand-name { font-family: 'DM Serif Display', serif; font-size: 18px; }
.brand-text .brand-name span { color: var(--accent); }
.brand-text .brand-sub { font-size: 10px; color: var(--text-dim); text-transform: uppercase; letter-spacing: 0.08em; }

/* App shell */
.topbar { display: flex; align-items: center; justify-content: space-between; padding: 14px 24px; border-bottom: 1px solid var(--border); background: rgba(11,15,30,0.85); backdrop-filter: blur(8px); position: sticky; top: 0; z-index: 10; }
.topbar-right { display: flex; align-items: center; gap: 10px; }
.user-chip-mini { font-size: 12px; color: var(--text-dim); padding: 6px 10px; background: var(--surface); border: 1px solid var(--border); border-radius: 8px; }

.chat-main { max-width: 980px; margin: 0 auto; padding: 24px; display: flex; flex-direction: column; height: calc(100vh - 67px); }

/* Thread */
.thread { flex: 1; overflow-y: auto; padding-right: 6px; padding-bottom: 12px; }
.thread::-webkit-scrollbar { width: 8px; }
.thread::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }

.empty-state { text-align: center; padding: 80px 12px; color: var(--text-dim); }
.empty-title { font-family: 'DM Serif Display', serif; font-size: 24px; color: var(--text); margin-bottom: 8px; }
.empty-sub { margin-bottom: 24px; font-size: 13px; }
.src-tag { font-family: 'JetBrains Mono', monospace; padding: 2px 8px; background: var(--surface); border: 1px solid var(--border); border-radius: 6px; color: var(--cyan); font-size: 11px; }
.suggested { display: flex; flex-direction: column; align-items: center; gap: 8px; margin-top: 20px; }
.suggest { background: var(--surface); border: 1px solid var(--border); color: var(--text); padding: 10px 14px; border-radius: 10px; font-size: 13px; cursor: pointer; font-family: inherit; transition: border-color .15s; max-width: 540px; text-align: left; width: 100%; }
.suggest:hover { border-color: var(--accent); }

.msg { margin-bottom: 18px; }
.msg-user { display: flex; justify-content: flex-end; }
.msg-user .bubble { background: var(--accent); color: white; padding: 10px 14px; border-radius: 14px 14px 4px 14px; max-width: 75%; }
.msg-agent .bubble { background: var(--surface); border: 1px solid var(--border); color: var(--text); padding: 14px 18px; border-radius: 14px 14px 14px 4px; max-width: 92%; line-height: 1.55; }
.msg-agent .bubble p { margin: 0 0 8px; }
.msg-agent .bubble p:last-child { margin-bottom: 0; }
.msg-agent .bubble ul, .msg-agent .bubble ol { margin: 8px 0; padding-left: 22px; }
.msg-agent .bubble li { margin-bottom: 4px; }
.msg-agent .bubble strong { color: var(--text); }
.msg-agent .bubble code { font-family: 'JetBrains Mono', monospace; font-size: 12px; padding: 1px 5px; background: var(--surface-2); border-radius: 4px; }
.msg-agent .bubble pre { background: var(--surface-2); padding: 10px; border-radius: 8px; overflow-x: auto; font-family: 'JetBrains Mono', monospace; font-size: 12px; }

.tool-trace { font-size: 11px; color: var(--text-muted); font-family: 'JetBrains Mono', monospace; padding: 6px 10px; background: rgba(110,139,255,0.08); border-left: 2px solid var(--accent); margin: 6px 0; border-radius: 0 6px 6px 0; }
.tool-trace.error { background: rgba(239,68,68,0.1); border-left-color: var(--red); color: #fca5a5; }

.citations { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }
.cite { display: inline-flex; align-items: center; gap: 6px; padding: 4px 10px; font-size: 11px; font-family: 'JetBrains Mono', monospace; background: var(--surface-2); border: 1px solid var(--border); border-radius: 6px; color: var(--text-dim); text-decoration: none; transition: border-color .15s, color .15s; }
.cite:hover { border-color: var(--accent); color: var(--text); }
.cite-label { color: var(--cyan); }

/* Ask form */
.ask-form { display: flex; gap: 8px; padding-top: 12px; border-top: 1px solid var(--border); }
.ask-form input { flex: 1; padding: 12px 16px; font-size: 14px; }
.ask-form .btn-primary { padding: 12px 22px; }

/* Toast */
.toast { position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%); padding: 12px 18px; background: var(--surface); border: 1px solid var(--border); border-radius: 8px; font-size: 13px; z-index: 200; box-shadow: 0 12px 30px rgba(0,0,0,0.4); }
.toast.error { border-color: var(--red); color: #fca5a5; }