:root { --bg: #0E1117; --panel: #161B22; --border: #222A35; --text: #E6EDF3; --muted: #8B949E; --accent: #3FB8AF; color-scheme: dark; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; place-items: center; padding: 16px;
  background: var(--bg); color: var(--text); font: 14px/1.5 "IBM Plex Sans", system-ui, sans-serif; }
form { width: min(340px, 100%); background: var(--panel); border: 1px solid var(--border); border-radius: 6px; padding: 28px; }
.brand { font: 12px ui-monospace, monospace; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); margin-bottom: 20px; }
label { display: block; color: var(--muted); font-size: 12px; margin-bottom: 14px; }
input { display: block; width: 100%; margin-top: 4px; padding: 9px 10px; background: var(--bg); color: var(--text);
  border: 1px solid var(--border); border-radius: 4px; font: inherit; }
input:focus { outline: none; border-color: var(--accent); }
button { width: 100%; padding: 10px; margin-top: 6px; background: var(--accent); color: #0E1117; border: 0; border-radius: 4px; font: 600 14px inherit; cursor: pointer; }
.error { color: #f0857a; font-size: 13px; margin: 0 0 10px; }