:root {
  --bg: #ffffff;
  --text: #1a1a1a;
  --accent: #000000;
  --gray: #f4f4f4;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  line-height: 1.6;
}

nav {
  display: flex;
  justify-content: space-between;
  padding: 1.2rem 10%;
  border-bottom: 1px solid #eee;
  align-items: center;
}

nav a,
.link-button {
  color: var(--text);
  text-decoration: none;
  background: none;
  border: none;
  cursor: pointer;
  font: inherit;
}

section {
  max-width: 600px;
  margin: 4rem auto;
  padding: 0 1rem;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: var(--gray);
  padding: 2rem;
  border-radius: 8px;
}

input {
  padding: 0.9rem;
  border: 1px solid #ddd;
  border-radius: 4px;
}

button {
  padding: 0.9rem;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}

button.secondary {
  background: white;
  color: black;
  border: 1px solid black;
}

#message {
  margin-top: 1rem;
}