Hostinger环境下自定义导航栏显示异常求助

我在把自己设计的自定义导航栏部署到Hostinger主机上时遇到了麻烦——导航栏的显示效果完全不符合预期，但在本地环境测试时是正常工作的。

我已经尝试了不少排查步骤，比如移除JavaScript相关元素、简化代码结构，但问题依然没有解决。

当前Hostinger上的导航栏异常显示效果如下：

以下是我使用的导航栏代码：

CSS 代码 #

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

body {
    font-family: 'Arial', sans-serif;
    color: #333;
    line-height: 1.6;
    background-color: #f4f4f9;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

/* Header styles */
.main-header {
    background: #0d47a1;
    color: white;
    padding: 1rem 0;
    position: relative;
    z-index: 1000;
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.main-header .logo {
    font-size: 1.8rem;
    font-weight: bold;
}

.menu-toggle {
    display: none;
}

.menu-label {
    display: none;
    font-size: 2rem;
    color: white;
    cursor: pointer;
}

.nav-menu {
    display: flex;
    flex-direction: row;
}

.main-header .nav-links {
    display: flex;
    gap: 1.5rem;
    position: relative;
}

.main-header .nav-links li {
    position: relative;
}

.main-header .nav-links a {
    color: white;
    font-size: 1rem;
    transition: color 0.3s ease;
    padding: 0.5rem 1rem;
    display: inline-block;
}

.main-header .nav-links a:hover {
    color: #683bff;
}

/* Dropdown Menu */
.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: #0d47a1;
    border-radius: 8px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    min-width: 150px;
    padding: 0.5rem 0;
}

.dropdown-menu li {
    margin: 0;
}

.dropdown-menu a {
    color: white;
    padding: 0.5rem 1rem;
    display: block;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.dropdown-menu a:hover {
    background: #003c8f;
}

/* Show dropdown on hover */
.nav-links li.dropdown:hover .dropdown-menu {
    display: block;
}

/* Responsive Design */
@media (max-width: 768px) {
    .menu-label {
        display: block;
    }

    .nav-menu {
        display: none;
        flex-direction: column;
        gap: 1rem;
        position: absolute;
        top: 100%;
        left: 0;
        background: #0d47a1;
        width: 100%;
        padding: 1rem 0;
        z-index: 1000;
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    }

    .menu-toggle:checked + .menu-label + .nav-menu {
        display: flex;
    }

    .nav-links {
        flex-direction: column;
        align-items: flex-start;
    }

    .nav-links a {
        padding: 0.5rem 1rem;
    }
}

HTML 代码 #

<!DOCTYPE html>
<html lang="en">
<head>
    <link rel="stylesheet" href="style/navbar.css">
</head>
<body>
    <header class="main-header">
        <div class="container">
            <h1 class="logo">Title</h1>

            <!-- Checkbox toggle for responsive menu -->
            <input type="checkbox" id="menu-toggle" class="menu-toggle" aria-label="Toggle navigation">
            <label for="menu-toggle" class="menu-label">☰</label>

            <nav class="nav-menu">
                <ul class="nav-links">
                    <li><a href="index.php">Home</a></li>
                    <li class="dropdown">
                        <a href="#">Services</a>
                        <ul class="dropdown-menu">
                            <li><a href="bootcamp.php">Bootcamps</a></li>
                            <li><a href="courses.php">Courses</a></li>
                            <li><a href="membership.php">Subscribe</a></li>
                        </ul>
                    </li>
                    <li class="dropdown">
                        <a href="#">Resources</a>
                        <ul class="dropdown-menu">
                            <li><a href="machines.php">Machines</a></li>
                            <li><a href="ctf.php">CTFs</a></li>
                            <li><a href="challenges.php">Challenges</a></li>
                        </ul>
                    </li>
                    <li class="dropdown">
                        <a href="#">Community</a>
                        <ul class="dropdown-menu">
                            <li><a href="forum.php">Forum</a></li>
                            <li><a href="events.php">Blogs</a></li>
                        </ul>
                    </li>
                    <li class="dropdown">
                        <a href="#">Our Team</a>
                        <ul class="dropdown-menu">
                            <li><a href="about.php">About</a></li>
                            <li><a href="contact.php">Contact</a></li>
                        </ul>
                    </li>
                    <?php
                    if (isset($_SESSION['user_id'])) {
                        echo '<li><a href="library.php">Library</a></li>';
                        echo '<li><a href="logout.php">Logout</a></li>';
                    } else {
                        echo '<li><a href="login.php">Login</a></li>';
                    }
                    ?>
                </ul>
            </nav>
        </div>
    </header>
</body>
</html>

备注：内容来源于stack exchange，提问作者salluc 1