:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b6b6b;
  --border: #dddddd;
  --accent: #2456c7;
  --error: #b42318;
  --success: #067647;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161616;
    --fg: #ededed;
    --muted: #a0a0a0;
    --border: #333333;
    --accent: #7aa2ff;
    --error: #ff8a80;
    --success: #6fd3a0;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.5;
}

a { color: var(--accent); }

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 48rem;
  margin: 0 auto;
  padding: 1rem;
  border-bottom: 1px solid var(--border);
}

.brand { font-weight: 700; text-decoration: none; color: var(--fg); }
.nav-links { display: flex; gap: 1rem; align-items: center; }

main { max-width: 48rem; margin: 0 auto; padding: 1rem; }

.card {
  max-width: 24rem;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: 8px;
}

.field { margin-bottom: 1rem; }
.field label { display: block; margin-bottom: 0.25rem; }
.field input {
  width: 100%;
  padding: 0.5rem;
  font: inherit;
  color: inherit;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 4px;
}
.field-error { color: var(--error); margin: 0.25rem 0 0; font-size: 0.9rem; }
.checkbox { margin-bottom: 1rem; }

.button {
  padding: 0.5rem 1rem;
  font: inherit;
  color: #fff;
  background: var(--accent);
  border: 0;
  border-radius: 4px;
  cursor: pointer;
}

.inline { display: inline; margin: 0; }
.link-button {
  padding: 0;
  font: inherit;
  color: var(--accent);
  background: none;
  border: 0;
  text-decoration: underline;
  cursor: pointer;
}

.welcome-image {
  display: block;
  max-width: 100%;
  height: auto;
  margin-top: 1rem;
  border-radius: 8px;
}

.flash { padding: 0.5rem 0.75rem; border-left: 4px solid var(--muted); }
.flash-error { border-color: var(--error); }
.flash-success { border-color: var(--success); }
.flash-info { border-color: var(--accent); }