:root {
  --fg: #1d2330;
  --muted: #5b6475;
  --bg: #ffffff;
  --soft: #f3f5f9;
  --accent: #2f5bd3;
  --warn: #9a3412;
  --line: #d9dee8;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.5;
}
body { margin: 0; }
.hero, main, footer { max-width: 60rem; margin: 0 auto; padding: 0 1.25rem; }
.hero { padding-top: 3rem; padding-bottom: 1.5rem; }
.kicker { color: var(--accent); font-weight: 600; margin: 0; }
h1 { font-size: clamp(1.8rem, 4vw, 2.6rem); line-height: 1.15; margin: 0.4rem 0 1rem; }
.lead { font-size: 1.15rem; color: var(--muted); max-width: 44rem; }
section { padding: 2rem 0; border-top: 1px solid var(--line); }
.cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(17rem, 1fr)); gap: 1.5rem; }
.card { background: var(--soft); border-radius: 0.75rem; padding: 0.25rem 1.25rem 1rem; }
.small { font-size: 0.9rem; color: var(--muted); }
.button, button {
  display: inline-block; font: inherit; font-weight: 600; cursor: pointer;
  background: var(--accent); color: #fff; border: 0; border-radius: 0.5rem;
  padding: 0.55rem 1rem; text-decoration: none;
}
.button.secondary { background: var(--soft); color: var(--accent); }
button:disabled, .button[aria-disabled="true"] { opacity: 0.45; cursor: not-allowed; }
input, select { font: inherit; padding: 0.45rem 0.6rem; border: 1px solid var(--line); border-radius: 0.4rem; }
.demo-controls { display: flex; flex-wrap: wrap; gap: 1rem; align-items: end; margin-bottom: 0.75rem; }
.demo-controls label { display: flex; flex-direction: column; font-size: 0.9rem; color: var(--muted); }
.chat { border: 1px solid var(--line); border-radius: 0.75rem; overflow: hidden; max-width: 32rem; }
.messages { height: 18rem; overflow-y: auto; padding: 0.75rem; display: flex; flex-direction: column; gap: 0.5rem; background: var(--soft); }
.messages > div { padding: 0.5rem 0.75rem; border-radius: 0.6rem; max-width: 85%; }
.messages .user { align-self: flex-end; background: var(--accent); color: #fff; }
.messages .bot, .messages .ai-disclosure-reply { align-self: flex-start; background: #fff; border: 1px solid var(--line); }
.messages .system { align-self: center; color: var(--muted); font-size: 0.85rem; }
.ai-disclosure-label { background: #eef2ff; color: #1e3a8a; font-weight: 600; font-size: 0.9rem; padding: 0.5rem 0.75rem; border-bottom: 1px solid var(--line); }
.messages .ai-disclosure-notice { align-self: stretch; max-width: none; background: #eef2ff; color: #1e3a8a; font-size: 0.9rem; text-align: center; }
.messages .ai-disclosure-crisis { align-self: stretch; max-width: none; background: #fff7ed; color: var(--warn); border: 1px solid #fdba74; }
.ai-disclosure-crisis ul { margin: 0.4rem 0 0; padding-left: 1.2rem; }
.ai-disclosure-crisis a { color: var(--warn); font-weight: 600; }
.chat-input { display: flex; gap: 0.5rem; padding: 0.6rem; border-top: 1px solid var(--line); }
.chat-input input { flex: 1; }
#signup-form { display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; }
#signup-form label { width: 100%; font-weight: 600; }
#signup-form input { flex: 1; min-width: 14rem; }
footer { padding-bottom: 3rem; border-top: 1px solid var(--line); }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
a { color: var(--accent); }