:root {
  --bg: #0b0d12;
  --panel: #11141b;
  --panel-2: #171b24;
  --text: #f2f4f8;
  --muted: #9ca5b5;
  --line: #262c38;
  --accent: #e8ecf5;
  --bubble-user: #1b2230;
  --bubble-ai: #12161e;
  --danger: #ff6b6b;
}
* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; background: var(--bg); color: var(--text); font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
body { padding: 0 16px 28px; }
button, textarea { font: inherit; }
button { cursor: pointer; }
.shell { width: min(920px, 100%); margin: 0 auto; min-height: 100vh; display: flex; flex-direction: column; }
.topbar { position: sticky; top: 0; z-index: 5; display: flex; justify-content: space-between; align-items: center; padding: 18px 0 14px; background: linear-gradient(var(--bg) 75%, transparent); backdrop-filter: blur(7px); }
.brand { display: flex; align-items: center; gap: 11px; }
.logo { width: 38px; height: 38px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 12px; background: var(--panel-2); font-weight: 800; text-transform: lowercase; }
.brand-name { font-size: 16px; font-weight: 750; }
.brand-sub { font-size: 12px; color: var(--muted); margin-top: 1px; }
.ghost { color: var(--muted); background: transparent; border: 1px solid var(--line); padding: 8px 12px; border-radius: 10px; }
.ghost:hover { color: var(--text); background: var(--panel); }
.hero { padding: 12vh 0 40px; text-align: center; }
.hero h1 { font-size: clamp(42px, 8vw, 76px); letter-spacing: -0.05em; line-height: .95; margin: 0; }
.hero p { max-width: 560px; margin: 18px auto 26px; color: var(--muted); font-size: 15px; line-height: 1.6; }
.chips { display: flex; flex-wrap: wrap; justify-content: center; gap: 9px; }
.chip { border: 1px solid var(--line); color: #c8cfdb; background: var(--panel); border-radius: 999px; padding: 9px 13px; }
.chip:hover { background: var(--panel-2); color: var(--text); }
.chat { display: flex; flex-direction: column; gap: 15px; padding-bottom: 22px; }
.message { display: flex; gap: 10px; }
.message.user { justify-content: flex-end; }
.bubble { max-width: min(760px, 92%); border: 1px solid var(--line); border-radius: 17px; padding: 13px 15px; line-height: 1.58; white-space: pre-wrap; overflow-wrap: anywhere; }
.user .bubble { background: var(--bubble-user); border-bottom-right-radius: 6px; }
.assistant .bubble { background: var(--bubble-ai); border-bottom-left-radius: 6px; }
.meta { color: var(--muted); font-size: 11px; margin-bottom: 5px; }
.typing { color: var(--muted); font-size: 13px; padding: 7px 2px; }
.composer { position: sticky; bottom: 10px; margin-top: auto; background: rgba(11,13,18,.9); backdrop-filter: blur(12px); border: 1px solid var(--line); border-radius: 18px; padding: 10px; box-shadow: 0 18px 50px rgba(0,0,0,.35); }
textarea { width: 100%; resize: none; max-height: 180px; min-height: 48px; border: 0; outline: 0; background: transparent; color: var(--text); padding: 10px 8px 6px; line-height: 1.5; }
textarea::placeholder { color: #70798a; }
.composer-row { display: flex; align-items: center; gap: 10px; padding: 5px 4px 2px; }
.status { color: #aeb7c6; font-size: 12px; }
.hint { margin-left: auto; color: #6f7888; font-size: 11px; }
.send { border: 0; background: var(--accent); color: #0d1016; border-radius: 10px; padding: 9px 13px; font-weight: 750; }
.send:disabled { opacity: .45; cursor: default; }
.footer { text-align: center; color: #616a7b; font-size: 11px; padding: 16px 0 2px; }
.error { color: var(--danger); }
@media (max-width: 650px) { .hero { padding-top: 9vh; } .hint { display: none; } .bubble { max-width: 96%; } body { padding-inline: 10px; } }