:root {
  --bg: #ffffff;
  --text: #000000;
  --card: #f1f1f1;
}

[data-theme="dark"] {
  --bg: #111111;
  --text: #ffffff;
  --card: #1e1e1e;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
}

nav {
  background: var(--card);
  padding: 15px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

nav a {
  text-decoration: none;
  color: var(--text);
  font-weight: bold;
  margin-right: 15px;
}

.container {
  padding: 20px;
}

.card {
  background: var(--card);
  padding: 20px;
  border-radius: 10px;
  margin-bottom: 20px;
}
.switch-btn {
  cursor: pointer;
  padding: 8px 12px;
  background: var(--text);
  color: var(--bg);
  border-radius: 8px;
}
input, select {
  width: 100%;
  padding: 12px;
  margin-top: 8px;
  margin-bottom: 12px;
  border-radius: 8px;
  border: 1px solid #999;
}
button {
  width: 100%;
  padding: 12px;
  background: #0066ff;
  border: none;
  color: white;
  font-size: 16px;
  border-radius: 8px;
  cursor: pointer;
}

button:hover {
  opacity: 0.85;
}