:root{color-scheme:light dark}
*{box-sizing:border-box}
body{margin:0;font:16px/1.5 system-ui,sans-serif;display:flex;flex-direction:column;height:100vh}
.center{margin:auto}.card{display:flex;flex-direction:column;gap:.6rem;min-width:16rem}
.card input,.card button{padding:.6rem;font-size:1rem}
.err{color:#c00;min-height:1.2em;margin:0}
.bar{display:flex;gap:.5rem;align-items:center;padding:.5rem;border-bottom:1px solid #8884}
.spacer{flex:1}
.log{flex:1;overflow-y:auto;padding:1rem;display:flex;flex-direction:column;gap:.75rem}
.msg{padding:.6rem .8rem;border-radius:.6rem;max-width:70ch;white-space:pre-wrap}
.msg.user{align-self:flex-end;background:#2563eb22}
.msg.assistant{align-self:flex-start;background:#8881}
.composer{display:flex;gap:.5rem;padding:.5rem;border-top:1px solid #8884}
.composer textarea{flex:1;resize:none;padding:.6rem;font:inherit}
.composer button{padding:0 1.2rem}