/* 简洁优雅的导航栏动态效果 */

/* 基础导航栏样式 */
.navbar {
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 滚动时导航栏效果 - 深蓝色渐变 */
.navbar.scrolled {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 50%, #4a7bc8 100%) !important;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25) !important;
}

/* 初始状态 - 浅蓝色渐变背景 */
.navbar:not(.scrolled) {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 50%, #4a7bc8 100%) !important;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1) !important;
}
+++++++ REPLACE</div>
</replace_in_file>

让我也优化一下JavaScript，确保滚动检测更加灵敏：

<replace_in_file>
<path>js/navbar-effects.js</path>
<diff>------- SEARCH
    function updateNavbar() {
        const scrollTop = window.pageYOffset || document.documentElement.scrollTop;
        
        if (scrollTop > 50) {
            navbar.classList.add('scrolled');
        } else {
            navbar.classList.remove('scrolled');
        }
        
        ticking = false;
    }
=======
    function updateNavbar() {
        const scrollTop = window.pageYOffset || document.documentElement.scrollTop;
        
        if (scrollTop > 20) { // 降低触发阈值，让效果更早出现
            navbar.classList.add('scrolled');
        } else {
            navbar.classList.remove('scrolled');
        }
        
        ticking = false;
    }

/* 导航链接悬停效果 - 简洁的下划线 */
.navbar-nav .nav-link {
    position: relative;
    transition: color 0.3s ease;
    padding-bottom: 8px !important;
}

.navbar-nav .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: rgba(255, 255, 255, 0.8);
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

.navbar-nav .nav-link:hover::after {
    width: 60%;
}

.navbar-nav .nav-link:hover {
    color: rgba(255, 255, 255, 0.9) !important;
}

/* 活跃链接效果 */
.navbar-nav .nav-link.active::after {
    width: 60%;
    background: #fff;
}

/* Logo 轻微悬停效果 */
.navbar-brand {
    transition: opacity 0.3s ease;
}

.navbar-brand:hover {
    opacity: 0.9;
}

/* 移动端菜单按钮 - 简洁动画 */
.navbar-toggler {
    border: none;
    padding: 0.25rem 0.5rem;
    transition: transform 0.2s ease;
}

.navbar-toggler:hover {
    transform: scale(1.05);
}

.navbar-toggler:focus {
    box-shadow: none;
}

/* 移动端菜单展开动画 */
.navbar-collapse {
    transition: all 0.3s ease;
}

/* 移动端导航链接 */
@media (max-width: 991.98px) {
    .navbar-nav .nav-link {
        padding: 0.75rem 1rem !important;
        margin: 0.25rem 0;
        border-radius: 6px;
        transition: all 0.3s ease;
    }
    
    .navbar-nav .nav-link:hover {
        background: rgba(255, 255, 255, 0.1);
        transform: translateX(8px);
    }
    
    .navbar-nav .nav-link::after {
        display: none;
    }
}

/* 页面加载时的淡入效果 */
.navbar {
    animation: fadeInDown 0.6s ease-out;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式优化 */
@media (max-width: 768px) {
    .navbar-brand {
        font-size: 1.1rem;
    }
}

/* 性能优化 */
.navbar-nav .nav-link,
.navbar-brand {
    will-change: transform;
}

/* 减少动画偏好设置 */
@media (prefers-reduced-motion: reduce) {
    .navbar,
    .navbar-nav .nav-link,
    .navbar-brand,
    .navbar-toggler,
    .navbar-collapse {
        transition: none;
        animation: none;
    }
}