:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --text: #16181d;
  --muted: #5c6370;
  --border: #d6d9e0;
  --field: #f8f9fb;
  --notice-bg: #fff6e0;
  --notice-text: #6b4a00;
  --accent: #2a5bd7;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111317;
    --card: #1b1e24;
    --text: #eceef2;
    --muted: #9aa1ad;
    --border: #343843;
    --field: #22262e;
    --notice-bg: #3a2f12;
    --notice-text: #f5d58a;
    --accent: #7b9cf0;
  }
}

* { box-sizing: border-box; }

html, body { margin: 0; }

body {
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.page {
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: 24px 16px;
}

.card {
  width: 100%;
  max-width: 400px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 32px 24px;
}

.brand {
  margin: 0 0 8px;
  font-size: 2rem;
  letter-spacing: -0.02em;
  color: var(--accent);
}

.title { margin: 0 0 16px; font-size: 1.5rem; }

.lead { margin: 0; color: var(--muted); font-size: 1.125rem; }

.notice {
  margin: 0 0 20px;
  padding: 12px 14px;
  border-radius: 10px;
  background: var(--notice-bg);
  color: var(--notice-text);
  font-size: 0.9375rem;
}

.login fieldset {
  border: 0;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 6px;
}

.login label { font-weight: 600; font-size: 0.9375rem; }

.login input {
  width: 100%;
  margin-bottom: 10px;
  padding: 12px;
  font: inherit;
  color: var(--text);
  background: var(--field);
  border: 1px solid var(--border);
  border-radius: 8px;
}

.login button {
  margin-top: 6px;
  padding: 12px;
  font: inherit;
  font-weight: 600;
  color: #fff;
  background: var(--accent);
  border: 0;
  border-radius: 8px;
}

.login fieldset:disabled input,
.login fieldset:disabled button {
  opacity: 0.55;
  cursor: not-allowed;
}