/* Base Styles */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --text-color: #343a40;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --border-color: #dee2e6;
    --font-family-sans-serif: 'Noto Sans SC', sans-serif;
}

body {
    font-family: var(--font-family-sans-serif);
    line-height: 1.6;
    color: var(--text-color);
    margin: 0;
    padding: 0;
    background-color: var(--bg-light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header */
.main-header {
    background-color: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0,0,0,.05);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.main-header .logo img {
    height: 40px;
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
}

.main-nav ul li {
    margin-left: 30px;
}

.main-nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    padding: 5px 0;
    transition: color 0.3s ease;
}

.main-nav ul li a:hover,
.main-nav ul li a.active {
    color: var(--primary-color);
}

.header-actions {
    display: flex;
    align-items: center;
}

.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.3s ease, color 0.3s ease;
    border: 1px solid transparent;
    cursor: pointer;
    margin-left: 10px;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--bg-white);
}

.btn-primary:hover {
    background-color: darken(var(--primary-color), 10%);
}

.btn-secondary {
    background-color: var(--bg-white);
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--bg-white);
}

.mobile-menu-toggle {
    display: none; /* Hidden by default on desktop */
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    margin-left: 15px;
}

.mobile-menu-toggle .icon-bar {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--text-color);
    margin: 5px 0;
    transition: all 0.3s ease;
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.98);
    z-index: 1001;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    transform: translateX(100%);
    transition: transform 0.3s ease-in-out;
}

.mobile-menu-overlay.open {
    transform: translateX(0);
}

.mobile-menu-overlay .close-button {
    position: absolute;
    top: 20px;
    right: 20px;
    font-size: 40px;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-color);
}

.mobile-menu-overlay nav ul {
    list-style: none;
    padding: 0;
    text-align: center;
}

.mobile-menu-overlay nav ul li {
    margin: 20px 0;
}

.mobile-menu-overlay nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 24px;
    font-weight: 500;
}

.mobile-menu-overlay .mobile-actions {
    margin-top: 30px;
    display: flex;
    gap: 15px;
}

/* Footer */
.main-footer {
    background-color: var(--text-color);
    color: var(--bg-light);
    padding: 40px 0 20px;
    font-size: 14px;
}

.main-footer h3 {
    color: var(--bg-white);
    font-size: 18px;
    margin-bottom: 20px;
}

.main-footer ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.main-footer ul li {
    margin-bottom: 10px;
}

.main-footer ul li a {
    text-decoration: none;
    color: var(--bg-light);
    transition: color 0.3s ease;
}

.main-footer ul li a:hover {
    color: var(--primary-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 20px;
    text-align: center;
}

.footer-bottom p {
    margin: 5px 0;
}

.footer-bottom a {
    color: var(--bg-light);
    text-decoration: none;
}

.footer-bottom a:hover {
    text-decoration: underline;
}

.social-links {
    margin-top: 15px;
}

.social-links a {
    display: inline-block;
    margin-right: 15px;
}

.social-links img {
    width: 24px;
    height: 24px;
    filter: invert(0.8);
    transition: filter 0.3s ease;
}

.social-links img:hover {
    filter: invert(1);
}

/* Responsive */
@media (max-width: 768px) {
    .main-nav, .header-actions .btn {
        display: none;
    }

    .mobile-menu-toggle {
        display: block;
    }

    .main-header .container {
        justify-content: space-between;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-col ul {
        padding-left: 0;
    }

    .footer-col.contact-info p {
        margin-bottom: 5px;
    }
}

/* Utility classes */
.text-center {
    text-align: center;
}

.mt-4 {
    margin-top: 1.5rem;
}

.mb-4 {
    margin-bottom: 1.5rem;
}

.py-5 {
    padding-top: 3rem;
    padding-bottom: 3rem;
}

/* Additional common elements */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

p {
    margin-top: 0;
    margin-bottom: 1rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

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

.form-control {
    display: block;
    width: 100%;
    padding: 0.5rem 0.75rem;
    font-size: 1rem;
    line-height: 1.5;
    color: var(--text-color);
    background-color: var(--bg-white);
    background-clip: padding-box;
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

.form-control:focus {
    color: var(--text-color);
    background-color: var(--bg-white);
    border-color: #80bdff;
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

textarea.form-control {
    min-height: 80px;
    resize: vertical;
}

/* Cards */
.card {
    background-color: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
    box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    margin-bottom: 1.5rem;
}

.card-body {
    padding: 1.25rem;
}

.card-title {
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
}

.card-text {
    margin-bottom: 0;
}

/* Alerts */
.alert {
    position: relative;
    padding: 0.75rem 1.25rem;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: 0.25rem;
}

.alert-success {
    color: #0f5132;
    background-color: #d1e7dd;
    border-color: #badbcc;
}

.alert-danger {
    color: #842029;
    background-color: #f8d7da;
    border-color: #f5c2c7;
}

.alert-info {
    color: #055160;
    background-color: #cff4fc;
    border-color: #b6effb;
}

.alert-warning {
    color: #664d03;
    background-color: #fff3cd;
    border-color: #ffecb5;
}

/* Buttons */
.btn-link {
    font-weight: 400;
    color: var(--primary-color);
    text-decoration: none;
}

.btn-link:hover {
    color: #0056b3;
    text-decoration: underline;
}

.btn-group {
    position: relative;
    display: inline-flex;
    vertical-align: middle;
}

.btn-group > .btn {
    position: relative;
    flex: 1 1 auto;
}

.btn-group > .btn:not(:first-child) {
    margin-left: -1px;
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

.btn-group > .btn:not(:last-child) {
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}

/* Lists */
.list-group {
    display: flex;
    flex-direction: column;
    padding-left: 0;
    margin-bottom: 0;
    border-radius: 0.25rem;
}

.list-group-item {
    position: relative;
    display: block;
    padding: 0.75rem 1.25rem;
    background-color: var(--bg-white);
    border: 1px solid rgba(0, 0, 0, 0.125);
}

.list-group-item:first-child {
    border-top-left-radius: inherit;
    border-top-right-radius: inherit;
}

.list-group-item:last-child {
    border-bottom-right-radius: inherit;
    border-bottom-left-radius: inherit;
}

.list-group-item + .list-group-item {
    border-top-width: 0;
}

.list-group-item-action {
    width: 100%;
    color: var(--text-color);
    text-align: inherit;
}

.list-group-item-action:hover,
.list-group-item-action:focus {
    z-index: 1;
    color: var(--text-color);
    text-decoration: none;
    background-color: #f8f9fa;
}
/* 移动端内容区防溢出（系统追加，请勿删除） */
@media (max-width: 768px) {
  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
  body {
    overflow-x: hidden;
  }
}