滚动到底部时如何更改导航条的颜色

Question

我有两个问题 问题1:我正在尝试更改滚动到底部时的导航栏背景颜色。我正在尝试添加类，但它无法覆盖引导程序！重要属性。但我已经用这行覆盖了它：

nav.scrolled {
background-color: #e8e4e1 !important;
box-shadow: 2px 10px 4px var(--section-bg-light);
}

问题2:如何在滚动到页面底部、页面页脚时使用javascript更改导航栏背景？

let navbar = document.querySelector('.navbar');
let section = document.querySelectorAll('section');
section.addEventListener('mouseover', addIt);
function addIt() {
navbar.classList.remove('bg-transparent');
navbar.classList.add('bg-dark');
}

nav.bg-dark {
background-color: #e8e4e1 !important;
}

<nav class="navbar navbar-expand-lg navbar-light bg-transparent fixed-top">
<div class="container-fluid">
<a class="navbar-brand" href="#"><img src="./img/logo-min.png" alt="JN-Fashion-Zone"></a>
<button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav">
<li class="nav-item home">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Products</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Services</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Contacts</a>
</li>
</ul>
</div>
</div>
</nav>

Answer 1

请查看如何覆盖！重要的您需要使用高特异性来覆盖！重要规则。尝试向选择器添加更多级别。

Answer 2

var nav = document.querySelector('nav');
window.addEventListener('scroll', function () {
if (window.pageYOffset > 100) {
nav.classList.add('bg-info', 'shadow');
} else {
nav.classList.remove('bg-info', 'shadow');
}
});