body {
  font-family: Arial, sans-serif;
  margin: 0;
  background: #f5f5f5;
}

#app {
  max-width: 960px;
  margin: 0 auto;
  padding: 20px;
  background: #fff;
  min-height: 100vh;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid #ddd;
  margin-bottom: 20px;
  padding-bottom: 10px;
}

h1 {
  margin: 0;
  font-size: 24px;
}

h2, h3 {
  margin-top: 0;
}

.hidden {
  display: none;
}

form {
  margin-bottom: 20px;
}

label {
  display: block;
  margin-bottom: 10px;
}

input {
  padding: 6px 8px;
  margin-top: 4px;
  width: 100%;
  box-sizing: border-box;
}

button {
  padding: 8px 12px;
  cursor: pointer;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 15px;
  font-size: 14px;
}

th, td {
  padding: 6px 8px;
  border: 1px solid #ddd;
  text-align: left;
}

th {
  background: #f0f0f0;
}

.error {
  color: #b00020;
  margin-top: 8px;
}

.info {
  color: #007700;
  margin-top: 8px;
}

#logoutBtn {
  background: #c0392b;
  color: #fff;
  border: none;
  border-radius: 3px;
}