body {
    display: flex;
    flex-direction: column;
    height: 100vh;
    margin: 0;
}

header, footer {
    background-color: #333;
    color: white;
    text-align: center;
    padding: 5px;
}

main {
    display: flex;
    flex: 1;
}

nav {
    background-color: #f4f4f4;
    width: 200px;
    padding: 1em;
}

nav a {
    display: block;
    margin: 1em 0;
    color: #333;
    text-decoration: none;
}

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

section {
    flex: 1;
    padding: 1em;
}


table {
    width: 100%;
    border-collapse: collapse;
    font-family: Arial, sans-serif;
}

th,
td {
    border: 1px solid #ddd;
    padding: 15px;
    text-align: center;
    vertical-align: middle;
}

th {
    background-color: #417893;
    color: white;
    font-weight: bold;
    text-align: center;
    vertical-align: middle;
}

tr:nth-child(even) {
    background-color: #f2f2f2;
}

thead tr th, tfoot tr th {
    text-align: center;
}

.form-group {
    margin-bottom: 15px;
}

.col-form-label {
    text-align: right;
}

.form-control {
    width: 100%;
}

.text-danger {
    font-size: 0.875em;
}

.form-text {
    color: #4CAF50; /* 默认帮助文本颜色 */
}

.form-text.text-muted {
    color: #417893; /* 可以根据需要修改颜色，例如：#6c757d 表示灰色 */
}

.text-danger {
    color: #dc3545; /* 错误文本颜色，红色 */
    font-size: 0.875em;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group .form-control {
    width: 100%;
}

.button-wrapper {
    text-align: center;
    margin-top: 1rem;
}

.btn-primary {
    padding: 0.5rem 2rem;
}