:root {
  /* CORE palette */
  --navy: #051C2C;
  --red: #CE1126;
  --pale: #D9E1F2;
  --white: #FFFFFF;
  --muted: #5A6B7A;

  --bg: var(--white);
  --fg: var(--navy);
  --accent: var(--red);
  --user-bg: var(--pale);
  --model-bg: var(--white);
  --border: var(--pale);
}
* { box-sizing: border-box; }
html { height: 100%; }
body { margin: 0; padding: 0; background: var(--bg); color: var(--fg); font: 15px/1.45 -apple-system, "Segoe UI", system-ui, sans-serif;
       display: flex; flex-direction: column; min-height: 100vh; min-height: 100dvh; }

header { flex: 0 0 auto; position: sticky; top: 0; z-index: 10;
         display: flex; justify-content: space-between; align-items: center;
         padding: 14px 22px; background: var(--navy); color: var(--white);
         border-bottom: 3px solid var(--red); }
.brand { color: var(--white); text-decoration: none; font-weight: 700; letter-spacing: 0.04em; text-transform: uppercase; font-size: 14px; }
.brand:hover { color: var(--white); opacity: 0.9; }
.logout { color: rgba(255,255,255,0.75); text-decoration: none; font-size: 13px; }
.logout:hover { color: var(--white); }

.muted { color: var(--muted); font-size: 13px; }
.error { color: var(--accent); }

/* ─── login ───────────────────────────────────────────────── */
.login-card { max-width: 380px; margin: 80px auto; padding: 32px; background: var(--white); border: 1px solid var(--border); border-radius: 6px; box-shadow: 0 2px 16px rgba(5,28,44,0.06); }
.login-card h1 { margin-top: 0; font-size: 22px; color: var(--navy); }
.login-card input[type=password] { width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 4px; font-size: 15px; margin-top: 8px; color: var(--fg); }
.login-card input[type=password]:focus { border-color: var(--navy); outline: none; }
.login-card button { margin-top: 14px; padding: 10px 16px; background: var(--accent); color: var(--white); border: 0; border-radius: 4px; font-size: 14px; font-weight: 600; cursor: pointer; }
.login-card button:hover { background: var(--navy); }

/* ─── chat layout: header (sticky) → head → messages (scroll) → composer (sticky bottom) ─── */
.chat { flex: 1; display: flex; flex-direction: column; max-width: 820px; width: 100%; margin: 0 auto;
        padding: 0 18px; min-height: 0; }
.chat-head { flex: 0 0 auto; padding: 24px 0 14px; }
.chat h1 { margin: 0 0 6px; font-size: 28px; font-weight: 700; letter-spacing: -0.01em; color: var(--navy); }
.chat-head > .muted { margin: 0; }

.messages { flex: 1 1 auto; overflow-y: auto; min-height: 0;
            padding: 4px 0 12px; -webkit-overflow-scrolling: touch; }
.msg { padding: 14px 16px; margin: 10px 0; border-radius: 8px; border: 1px solid var(--border); }
.msg.user { background: var(--user-bg); border-color: transparent; }
.msg.model { background: var(--model-bg); border-left: 3px solid var(--red); }
.msg.thinking { color: var(--muted); font-style: italic; border-left-color: var(--pale); }
.msg p { margin: 0.5em 0; }
.msg p:first-child { margin-top: 0; }
.msg p:last-child { margin-bottom: 0; }
.msg a { color: var(--navy); font-weight: 600; }
.msg a:hover { color: var(--accent); }
.msg ul, .msg ol { margin: 8px 0; padding-left: 22px; }
.msg li { margin: 3px 0; }
.msg strong { color: var(--navy); }
.msg em { font-style: italic; }
.msg h1, .msg h2, .msg h3, .msg h4 { color: var(--navy); margin: 14px 0 6px; }
.msg h1 { font-size: 20px; } .msg h2 { font-size: 18px; } .msg h3 { font-size: 16px; } .msg h4 { font-size: 15px; }
.msg code { background: rgba(5,28,44,0.06); padding: 1px 5px; border-radius: 3px; font-family: ui-monospace, "SF Mono", Menlo, monospace; font-size: 13px; }
.msg pre { background: rgba(5,28,44,0.06); padding: 10px 12px; border-radius: 4px; overflow-x: auto; }
.msg pre code { background: transparent; padding: 0; }
.msg blockquote { border-left: 3px solid var(--pale); margin: 8px 0; padding: 2px 12px; color: var(--muted); }
.msg table { border-collapse: collapse; margin: 8px 0; font-size: 13px; }
.msg th, .msg td { border: 1px solid var(--border); padding: 6px 10px; text-align: left; }
.msg th { background: rgba(5,28,44,0.04); }

.usage { margin-top: 10px; font-size: 11px; color: var(--muted);
         font-family: ui-monospace, "SF Mono", Menlo, monospace; letter-spacing: 0.02em; }
.calls { margin-top: 8px; font-size: 12px; color: var(--muted); }
.calls summary { cursor: pointer; }
.calls pre { background: rgba(5,28,44,0.04); padding: 10px; border-radius: 4px; overflow-x: auto; white-space: pre-wrap; color: var(--fg); }

.no-tools-warning { margin-top: 10px; padding: 10px 12px;
                    background: rgba(206,17,38,0.08); border: 1px solid var(--accent);
                    border-radius: 4px; color: var(--accent); font-size: 13px; line-height: 1.4; }
.no-tools-warning strong { color: var(--accent); }

/* Hallucination grounding: red banner + inline strike-through on links
   whose href didn't come from any tool result this turn. */
.ungrounded-banner { margin: 0 0 12px; padding: 10px 12px;
                     background: var(--accent); color: var(--white);
                     border-radius: 4px; font-size: 13px; line-height: 1.4; }
.ungrounded-banner strong { color: var(--white); }
.ungrounded-banner code { background: rgba(255,255,255,0.18); color: var(--white);
                          padding: 1px 4px; border-radius: 3px; }
.msg a.flagged-link { color: var(--accent); text-decoration: line-through;
                      text-decoration-thickness: 2px;
                      background: rgba(206,17,38,0.08); padding: 0 4px; border-radius: 3px; }
.msg a.flagged-link::before { content: "🚨 "; text-decoration: none; display: inline-block; }

/* ─── composer pinned at bottom ─── */
.chat-form { flex: 0 0 auto; position: sticky; bottom: 0; z-index: 5;
             padding: 12px 0 16px; padding-bottom: calc(16px + env(safe-area-inset-bottom));
             background: var(--bg); border-top: 1px solid var(--border); }
.chat-form textarea { width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 4px; font-size: 15px; font-family: inherit; resize: vertical; color: var(--fg); }
.chat-form textarea:focus { border-color: var(--navy); outline: none; }
.chat-form .row { display: flex; justify-content: space-between; align-items: center; margin-top: 8px; gap: 10px; flex-wrap: wrap; }
.chat-form .actions { display: flex; gap: 8px; }
.chat-form button { padding: 8px 16px; border: 1px solid var(--border); border-radius: 4px; background: var(--white); color: var(--fg); cursor: pointer; font-size: 14px; min-height: 40px; }
.chat-form #reset:hover { border-color: var(--navy); }
.chat-form #send { background: var(--accent); color: var(--white); border-color: var(--accent); font-weight: 600; }
.chat-form #send:hover { background: var(--navy); border-color: var(--navy); }
.chat-form #send:disabled { opacity: 0.6; cursor: wait; }

/* ─── narrow viewports (phones in portrait, narrow tablets) ─── */
@media (max-width: 600px) {
  .chat { padding: 0 12px; }
  .chat-head { padding: 14px 0 10px; }
  .chat h1 { font-size: 22px; }
  .chat-head > .muted { font-size: 12px; }
  header { padding: 10px 14px; }
}

/* ─── short viewports (phones in landscape, ≤500px tall) ─── */
@media (max-height: 500px) {
  .chat-head { padding: 8px 0 4px; }
  .chat h1 { font-size: 18px; margin: 0; }
  .chat-head > .muted { display: none; }
  .chat-form { padding: 6px 0 10px; }
  .chat-form textarea { font-size: 14px; padding: 8px 10px; }
  .chat-form .row { margin-top: 6px; }
  .msg { padding: 10px 12px; margin: 6px 0; }
  header { padding: 6px 14px; border-bottom-width: 2px; }
  .brand { font-size: 13px; }
}