:root{--border: #eee;--muted: #666;--accent: #0ea5e9;--bg: #ffffff;--bubble-me: #dcfce7;--bubble-me-text: #065f46;--bubble-other: #f1f5f9;--bubble-other-text: #0f172a}html,body,#root{height:100%}*{box-sizing:border-box}body{margin:0;background:var(--bg)}.app{height:100vh;display:flex;flex-direction:column;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}.header{padding:12px 16px;border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:space-between}.main-grid{flex:1;min-height:0;display:grid;grid-template-columns:280px 1fr}.sidebar{border-right:1px solid var(--border);padding:12px;min-width:0}input[type=text],input[type=email],input[type=password]{border:1px solid var(--border);border-radius:8px;padding:8px}button{border:1px solid var(--border);border-radius:8px;background:#fff;cursor:pointer}button:hover{background:#f8fafc}@media (max-width: 1024px){.main-grid{grid-template-columns:240px 1fr}}@media (max-width: 480px){.main-grid{grid-template-columns:1fr}.msg{max-width:88%;font-size:13px}}.day-sep{color:#666;font-size:12px;text-align:center;margin:8px 0}.ticks{font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}.msg{max-width:72%;padding:8px 10px;border-radius:12px;font-size:14px;line-height:1.35}.msg-me{background:#dcf8c6;border-top-right-radius:4px;color:var(--bubble-me-text)}.msg-other{background:#fff;border:1px solid #eee;border-top-left-radius:4px;color:var(--bubble-other-text)}.call-banner button{box-shadow:0 1px #0000000d}