:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --accent-color: #f39c12;
    --light-color: #f8f9fa;
    --dark-color: #1a1a1a;
    --header-color: #111;
    --card-bg: #ffffff;
}

body {
    font-family: 'Helvetica Neue', Arial, 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f7fa;
}

.main-navbar {
    background: var(--header-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.main-navbar .navbar-brand {
    color: white;
    font-weight: 700;
    font-size: 1.5rem;
}

.main-navbar .navbar-nav .nav-link {
    color: white !important;
    font-weight: 500;
    padding: 15px 20px;
    transition: all 0.3s;
}

.main-navbar .navbar-nav .nav-link:hover {
    background-color: rgba(255,255,255,0.1);
    border-radius: 4px;
}

.breadcrumb-wrapper {
    background-color: white;
    padding: 15px 0;
    margin-bottom: 30px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.breadcrumb {
    background: transparent;
    margin-bottom: 0;
    padding: 0;
}

.breadcrumb-item a {
    color: var(--primary-color);
}

footer {
    background: var(--header-color);
    color: white;
    padding: 40px 0 20px;
    margin-top: 50px;
}

footer a {
    color: #ddd;
}

footer a:hover {
    color: white;
}

.scroll-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 1000;
}

.scroll-to-top button {
    background: var(--primary-color);
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.2);
    transition: all 0.3s;
}

.scroll-to-top button:hover {
    background: var(--secondary-color);
    transform: translateY(-3px);
}

/* 响应式调整 */
@media (max-width: 768px) {
    .post-navigation {
        flex-direction: column;
    }
    
    .previous-post, .next-post {
        flex: 0 0 100%;
        margin-bottom: 20px;
    }
    
    .post-header {
        padding: 20px;
    }
    
    .post-title {
        font-size: 1.5rem;
    }
}

/* 加载动画 */
.loading-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
    margin-right: 10px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}