body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    margin: 0;
    padding: 0;
    background-color: #f4f7f6;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: #2c3e50;
    color: white;
    padding: 1rem 2rem;
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header a {
    color: #ecf0f1;
    text-decoration: none;
    margin-left: 15px;
    font-size: 0.9rem;
}

header a:hover {
    text-decoration: underline;
}

.card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 30px;
    margin: 20px 0;
    width: 100%;
    box-sizing: border-box;
}

.card-center {
    text-align: center;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

h2 {
    border-bottom: 2px solid #2c3e50;
    padding-bottom: 10px;
    margin-top: 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: white;
    table-layout: fixed;
}

th, td {
    padding: 12px;
    border: 1px solid #ddd;
    text-align: left;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

th {
    background-color: #f8f9fa;
    color: #2c3e50;
}

tr:hover {
    background-color: #f1f1f1;
}

.col-main {
    width: auto;
}

.col-side {
    width: 300px;
}

.btn {
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
    text-decoration: none;
    display: inline-block;
}

.btn-primary {
    background-color: #3498db;
    color: white;
}

.btn-success {
    background-color: #27ae60;
    color: white;
}

.btn-danger {
    background-color: #e74c3c;
    color: white;
}

.btn-outline {
    background: none;
    border: 1px solid #3498db;
    color: #3498db;
}

input[type="text"], input[type="password"], select {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    width: 100%;
    box-sizing: border-box;
    margin-bottom: 15px;
}

.form-inline {
    display: flex;
    gap: 10px;
    align-items: center;
}

.form-inline input, .form-inline select {
    margin-bottom: 0;
    flex-grow: 1;
}

.flash-messages {
    padding: 15px;
    margin-bottom: 20px;
    border-radius: 4px;
}

.flash-error {
    color: #721c24;
    background-color: #f8d7da;
    border: 1px solid #f5c6cb;
}

.flash-success {
    color: #155724;
    background-color: #d4edda;
    border: 1px solid #c3e6cb;
}