:root {
  color-scheme: light;
  --bg: #f4f5f7;
  --card-bg: #ffffff;
  --text: #1f2430;
  --muted: #5c6370;
  --accent: #2f6f4f;
  --error: #b3261e;
  --border: #d9dce1;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 2rem 1rem;
  background: var(--bg);
  color: var(--text);
  font-family: "Hiragino Sans", "Yu Gothic", "Segoe UI", sans-serif;
  line-height: 1.6;
}

.card {
  max-width: 480px;
  margin: 0 auto;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 2rem;
}

h1 {
  margin-top: 0;
  font-size: 1.5rem;
}

h1.success {
  color: var(--accent);
}

h1.error {
  color: var(--error);
}

.name {
  color: var(--muted);
  margin-bottom: 1.5rem;
}

fieldset {
  border: 1px solid var(--border);
  border-radius: 6px;
  margin-bottom: 1rem;
  padding: 0.75rem 1rem;
}

legend {
  padding: 0 0.5rem;
  font-weight: 600;
}

label {
  display: block;
  margin: 0.4rem 0;
}

button {
  width: 100%;
  padding: 0.75rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  font-size: 1rem;
  cursor: pointer;
}

button:hover {
  opacity: 0.9;
}