:root { --bg: #f4f5f7; --panel: #fff; --border: #e3e5e9; --text: #1b1f24; --accent: #2f6fde; --down: #d64545; color-scheme: light; }
@media (prefers-color-scheme: dark) {
  :root { --bg: #0f1216; --panel: #161a20; --border: #262c35; --text: #e6e9ee; --accent: #6aa0ff; --down: #f06464; 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/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
form { width: 100%; max-width: 320px; background: var(--panel); border: 1px solid var(--border); border-radius: 10px;
  padding: 24px; display: flex; flex-direction: column; gap: 12px; }
h1 { font-size: 18px; margin: 0 0 4px; }
#err { color: var(--down); margin: 0; min-height: 1em; font-size: 13px; }
label { display: flex; flex-direction: column; gap: 4px; font-size: 13px; }
input { font: inherit; color: inherit; background: var(--bg); border: 1px solid var(--border); border-radius: 6px; padding: 8px 10px; }
button { font: inherit; font-weight: 600; background: var(--accent); color: #fff; border: 0; border-radius: 6px; padding: 9px; cursor: pointer; }