:root {
    --primary: #3b82f6;
    --primary-rgb: 59, 130, 246;
    --primary-light: #60a5fa;
    --dark: #0f172a;
    --dark-light: #1e293b;
    --gray: #64748b;
    --light: #f8fafc;
    --card-bg: rgba(30, 41, 59, 0.7);
    --card-border: rgba(255, 255, 255, 0.08);
    --bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    --text-color: #e2e8f0;
    --text-color-secondary: #64748b;
    --time-color: #f1f5f9;
    --date-color: #94a3b8;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --accent-color: var(--primary);
    --bg-image: url('https://images.unsplash.com/photo-1506905925346-21bda4d32df4?w=800&q=80');
}



[data-theme="light"] {
    --primary: #FF9800;
    --primary-rgb: 255, 152, 0;
    --primary-light: #FFB74D;
    --dark: #424242;
    --dark-light: #616161;
    --gray: #757575;
    --light: #FFFFFF;
    --card-bg: rgba(255, 255, 255, 0.95);
    --card-border: rgba(255, 255, 255, 0.1);
    --bg-gradient: rgba(255, 255, 255, 0.92);
    --text-color: #333333;
    --text-color-secondary: #757575;
    --time-color: #212121;
    --date-color: #616161;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --accent-color: var(--primary);
}


[data-theme="light"] .logo-subtitle {
    color: #000000;
}




* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    background: var(--bg-gradient);
    color: var(--text-color);
    min-height: 100vh;
    line-height: 1.5;
    transition: background-color 0.3s ease, color 0.3s ease;
}


body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: var(--bg-image);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0.1;
    z-index: -1;
    transition: opacity 0.3s ease;
}



[data-theme="light"] body::before {
    opacity: 0.1;
}




.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 1;
}


.fixed-header {
    width: 100%;
    z-index: 10;
    padding-bottom: 20px;
    margin-top: 90px;
}


.page-container {
    margin-top: 20px;
    min-height: calc(100vh - 300px);
}




.page {
    display: none;
    opacity: 0;
}


.page.active {
    display: block;
    animation: pageFadeIn 0.5s ease forwards;
}


.page-header {
    margin-bottom: 40px;
    padding-top: 30px;
}




.logo-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 30px;
}


.logo-image {
    width: 120px;
    height: 120px;
    margin-bottom: 20px;
}


.logo-subtitle {
    font-size: 1.8rem;
    font-weight: 300;
    color: #3B82F6;
    text-align: center;
    margin-bottom: 10px;
}


.date-display-full {
    font-size: 1rem;
    font-weight: 300;
    color: var(--date-color);
    text-align: center;
    margin-top: 5px;
    opacity: 0.9;
}




.footer {
    text-align: center;
    padding: 25px;
    margin-top: 40px;
    color: var(--gray);
    font-size: 0.9rem;
    border-top: 1px solid var(--card-border);
}


.footer-info {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 25px;
    margin-top: 15px;
    flex-wrap: wrap;
}


.info-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
}


.beian-link {
    color: var(--gray);
    text-decoration: none;
    transition: color 0.2s ease;
}

.beian-link:hover {
    color: var(--primary-light);
}


.copyright-link {
    color: var(--gray);
    text-decoration: none;
    transition: color 0.2s ease;
}

.copyright-link:hover {
    color: var(--primary-light);
}




@keyframes pageFadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}




.copyright-header-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--card-bg);
    border-bottom: 1px solid var(--card-border);
    backdrop-filter: blur(10px);
    z-index: 1001;
    padding: 15px 0;
}


.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}


.header-right {
    margin-left: auto;
}


.back-btn {
    background: var(--primary);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 8px;
    font-size: 0.9rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s ease;
    text-decoration: none;
}


.back-btn:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}


html[data-theme="dark"] #copyright-theme-slider {
    left: 52px;
}


html[data-theme="light"] #copyright-light-btn {
    color: white;
}


html[data-theme="dark"] #copyright-dark-btn {
    color: white;
}


.copyright-main {
    margin-top: 80px;
    padding: 20px;
    min-height: calc(100vh - 80px);
}


.copyright-content-wrapper {
    max-width: 900px;
    margin: 0 auto;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 8px 32px var(--shadow-color);
}


.copyright-header {
    text-align: center;
    margin-bottom: 50px;
    padding-bottom: 30px;
    border-bottom: 2px solid var(--card-border);
}


.copyright-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-color);
}


.copyright-meta {
    color: var(--gray);
    font-size: 0.95rem;
}

.copyright-meta p {
    margin: 5px 0;
}


.copyright-content {
    line-height: 1.8;
    color: var(--text-color);
}


.copyright-section {
    margin-bottom: 40px;
    padding: 25px;
    background: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--card-border);
    backdrop-filter: blur(10px);
}


.copyright-section h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--primary);
    border-bottom: 2px solid rgba(59, 130, 246, 0.4);
    padding-bottom: 8px;
}


.copyright-section h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin: 25px 0 15px 0;
    color: var(--text-color);
}


.copyright-section p {
    margin-bottom: 15px;
    text-align: justify;
}


.copyright-section strong {
    color: var(--primary);
    font-weight: 600;
}


.contact-info {
    background: rgba(var(--primary-rgb), 0.1);
    padding: 20px;
    border-radius: 8px;
    border-left: 4px solid rgba(59, 130, 246, 0.4);
    margin-top: 20px;
}


.contact-info h3 {
    margin-top: 0;
    color: var(--primary);
}


.contact-info p {
    margin-bottom: 10px;
}


.copyright-footer {
    text-align: center;
    margin-top: 50px;
    padding: 30px;
    background: rgba(var(--primary-rgb), 0.1);
    border-radius: 12px;
    border: 1px solid var(--card-border);
}


.copyright-footer p {
    margin-bottom: 10px;
    font-size: 1.1rem;
}


.copyright-actions {
    text-align: center;
    margin-top: 30px;
}


.back-btn {
    padding: 12px 30px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 25px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}


.back-btn:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(var(--primary-rgb), 0.4);
}




[data-theme="dark"] .copyright-page {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}


[data-theme="light"] .copyright-section {
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid rgba(0, 0, 0, 0.1);
}


[data-theme="light"] .copyright-footer {
    background: rgba(255, 152, 0, 0.1);
    border: 1px solid rgba(255, 152, 0, 0.2);
}



@media (max-width: 768px) {
    
    .copyright-header-bar {
        padding: 10px 0;
    }
    
    
    .header-container {
        padding: 0 15px;
    }
    
    
    .back-btn {
        padding: 8px 16px;
        font-size: 0.85rem;
    }
    
    
    .copyright-main {
        margin-top: 70px;
        padding: 15px;
    }
    
    
    .copyright-content-wrapper {
        padding: 25px 20px;
    }
    
    
    .copyright-container {
        padding: 20px 15px;
    }
    
    
    .copyright-header h1 {
        font-size: 2rem;
    }
    
    
    .copyright-section {
        padding: 20px 15px;
    }
    
    
    .footer-info {
        flex-direction: column;
        gap: 15px;
    }
}