:root {
  color-scheme: light dark;
  --bg: #f4f6f8;
  --fg: #1b2430;
  --muted: #5b6775;
  --card: #ffffff;
  --line: #d8dee6;
  --accent: #1f6feb;
  --danger-bg: #fde8e8;
  --danger-fg: #8a1f1f;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --fg: #e6edf3;
    --muted: #9aa7b4;
    --card: #161b22;
    --line: #30363d;
    --accent: #58a6ff;
    --danger-bg: #3d1d1d;
    --danger-fg: #ffb4b4;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.card {
  width: 100%;
  max-width: 380px;
  padding: 28px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
}

h1 {
  margin: 0 0 4px;
  font-size: 24px;
  letter-spacing: -0.02em;
}

.muted {
  margin: 0 0 22px;
  color: var(--muted);
  font-size: 14px;
}

label {
  display: block;
  margin: 14px 0 6px;
  font-size: 14px;
  font-weight: 600;
}

input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--bg);
  color: var(--fg);
  font: inherit;
}

input:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

button {
  width: 100%;
  margin-top: 20px;
  padding: 11px 14px;
  border: 0;
  border-radius: 6px;
  background: var(--accent);
  color: #ffffff;
  font: inherit;
  font-weight: 650;
  cursor: pointer;
}

button:hover { filter: brightness(1.08); }
button:focus-visible { outline: 2px solid var(--fg); outline-offset: 2px; }

.alert {
  display: none;
  margin: 0 0 16px;
  padding: 10px 12px;
  border-radius: 6px;
  background: var(--danger-bg);
  color: var(--danger-fg);
  font-size: 14px;
}

/* No JavaScript: the login handler redirects to /#error or /#throttled. */
#error:target,
#throttled:target {
  display: block;
}

.foot {
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}