:root { --fg: #1a2233; --bg: #f4f6fb; --accent: #2b5cff; }
* { box-sizing: border-box; }
body { font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif; color: var(--fg);
  background: var(--bg); margin: 0; padding: 0 16px; line-height: 1.5; }
header { padding: 24px 0 8px; border-bottom: 1px solid #d7ddea; }
h1 { margin: 0 0 4px; font-size: 1.4rem; }
nav, footer { color: #5a6782; font-size: 0.9rem; }
main { padding: 16px 0; max-width: 860px; }
code { background: #e7ecf7; padding: 1px 5px; border-radius: 4px; font-size: 0.85em; }
ul { padding-left: 20px; }
form label { display: block; margin: 8px 0; }
input { padding: 6px 8px; border: 1px solid #c3cbdd; border-radius: 6px; min-width: 240px; }
button { padding: 7px 14px; border: 0; border-radius: 6px; background: var(--accent);
  color: #fff; cursor: pointer; }
.msg { padding: 4px 0; }