:root { color-scheme: dark; --ink: #efece2; --muted: #aaa69d; --line: #30322d; --paper: #151714; --field: #1d201b; --acid: #c7fa55; }
* { box-sizing: border-box; }
body { margin: 0; background: #0c0d0b; color: var(--ink); font: 16px/1.55 ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace; }
.shell { width: min(900px, calc(100% - 32px)); min-height: 100svh; margin: auto; display: grid; grid-template-rows: auto 1fr auto; }
header { padding: 32px 0 22px; border-bottom: 1px solid var(--line); }
.brand { color: var(--ink); text-decoration: none; letter-spacing: .12em; font-size: 14px; font-weight: 700; }
.brand span { color: var(--acid); }
header p { color: var(--muted); margin: 12px 0 0; max-width: 620px; font-size: 14px; }
.chat { min-height: 0; display: grid; grid-template-rows: 1fr auto; }
.messages { padding: 32px 0; display: flex; flex-direction: column; gap: 18px; overflow-y: auto; }
.message { max-width: 78%; padding: 16px 18px; border: 1px solid var(--line); border-radius: 3px; white-space: pre-wrap; }
.message p { margin: 0; }
.message small { display: block; margin-top: 9px; color: var(--muted); font-size: 12px; }
.message.user { align-self: end; background: var(--acid); border-color: var(--acid); color: #14150f; }
.message.assistant { align-self: start; background: var(--paper); }
.composer { display: grid; grid-template-columns: 1fr auto; gap: 10px; padding: 20px 0 28px; border-top: 1px solid var(--line); }
textarea { width: 100%; resize: vertical; min-height: 54px; max-height: 240px; padding: 14px; background: var(--field); color: var(--ink); border: 1px solid #454941; border-radius: 3px; font: inherit; }
textarea:focus { outline: 1px solid var(--acid); border-color: var(--acid); }
button { align-self: end; min-height: 54px; padding: 0 18px; border: 1px solid var(--acid); border-radius: 3px; background: var(--acid); color: #15170f; cursor: pointer; font: inherit; font-weight: 700; }
button:disabled { opacity: .55; cursor: wait; }
button span { font-size: 20px; }
footer { padding: 18px 0 25px; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.sr-only { position:absolute; width:1px; height:1px; padding:0; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0; }
@media (max-width: 600px) { .shell { width: min(100% - 24px, 900px); } .message { max-width: 92%; } .composer { grid-template-columns: 1fr; } button { width: 100%; } }