:root {
  color-scheme: light dark;
  --bg: #f5f5f4;
  --fg: #1a1a18;
  --card-bg: #ffffff;
  --accent: #1f3d2b;
  --accent-fg: #ffffff;
  --muted: #5b5b57;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14140f;
    --fg: #f2f2ee;
    --card-bg: #1f1f19;
    --accent: #4f8f66;
    --accent-fg: #0a1a10;
    --muted: #a8a89f;
  }
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
}

.page {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.card {
  width: 100%;
  max-width: 26rem;
  background: var(--card-bg);
  border-radius: 12px;
  padding: 48px 32px;
  text-align: center;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.08);
}

.brand {
  margin: 0 0 8px;
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.tagline {
  margin: 0 0 32px;
  font-size: 1rem;
  color: var(--muted);
}

.signin {
  display: inline-block;
  width: 100%;
  padding: 14px 24px;
  border-radius: 8px;
  background: var(--accent);
  color: var(--accent-fg);
  text-decoration: none;
  font-size: 1rem;
  font-weight: 600;
}

.signin:hover {
  opacity: 0.92;
}

.signin:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.footer {
  padding: 16px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--muted);
}

@media (max-width: 360px) {
  .card {
    padding: 36px 20px;
  }

  .brand {
    font-size: 1.5rem;
  }
}