body {
  font-family: Tahoma, Arial, sans-serif;
  background: #f6f7fb;
  margin: 0;
}
.container {
  max-width: 900px;
  margin: 40px auto;
  background: #fff;
  padding: 24px;
  border-radius: 12px;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.06);
}
h1 {
  margin-top: 0;
}
nav a {
  margin-inline-end: 10px;
  text-decoration: none;
  color: #2563eb;
}
label {
  display: block;
  margin: 10px 0 4px;
}
input,
textarea,
button {
  width: 100%;
  padding: 10px;
  margin-bottom: 12px;
  border: 1px solid #ddd;
  border-radius: 8px;
}
button {
  cursor: pointer;
}
.alert {
  background: #fee2e2;
  border: 1px solid #fecaca;
  color: #b91c1c;
  padding: 10px;
  border-radius: 8px;
  margin-bottom: 12px;
}
#family-tree {
  padding: 16px;
  border: 1px solid #eee;
  border-radius: 8px;
  background: #fafafa;
}