:root {
  --bg-color: #f4f7f9;
  --panel-bg: #ffffff;
  --border-color: #e2e8f0;
  --primary-color: #3498db;
  --primary-hover: #2980b9;
  --text-color: #333;
  --label-color: #555;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
}

.login-panel {
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  box-shadow: 0 4px 6px rgba(0,0,0,0.05);
  padding: 40px;
  width: 100%;
  max-width: 400px;
}

h1 {
  color: var(--primary-color);
  text-align: center;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 10px;
  margin-top: 0;
  margin-bottom: 30px;
}

label {
  display: block;
  color: var(--label-color);
  font-size: 14px;
  margin-bottom: 6px;
}

input[type="email"],
input[type="password"] {
  width: 100%;
  padding: 10px;
  border: 1px solid var(--border-color);
  border-radius: 5px;
  font-size: 14px;
  margin-bottom: 20px;
}

button {
  width: 100%;
  padding: 12px;
  font-size: 16px;
  font-weight: bold;
  color: #fff;
  background-color: var(--primary-color);
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.2s;
}

button:hover {
  background-color: var(--primary-hover);
}

.error-message {
  color: red;
  font-size: 14px;
  text-align: center;
  margin-bottom: 15px;
}

.footer {
  text-align: center;
  margin-top: 15px;
  font-size: 13px;
  color: #777;
}