/* 顶部导航栏的样式 */
.navbar {
    position: absolute;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-width: 1px;
    padding: 5px 20px;
    color: white;
    top: 0;
    width: 100%;
    z-index: 1000;
    box-sizing: border-box;
}

/*下滑时将导航栏固定并且修改链接颜色为黑色*/
.navbar.fixed {
    position: fixed;
    border-style: solid;
    border-color: white white #dddddd white;
    border-width: 1px;
    background-color: white;
}

.navbar.fixed ul li a {
    color: black;
}

.navbar.fixed.logo img {
    visibility: visible;
}

/* 网站Logo或标题 */
#logo {
    visibility: hidden;
}

/* 导航链接的样式 */
.navbar ul {
    list-style: none;
    display: flex;
    margin: 0;
    padding: 0;
}

.navbar ul li {
    margin: 0 40px 0 0;
}

.navbar ul li a {
    text-decoration: none;
    color: white;
    font-size: 20px;
    display: block;
    padding: 5px 0;
}

.navbar ul li a:hover {
    color: #ddd;
}

/* 移动端汉堡菜单 */
.menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 5px;
    z-index: 1001;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 3px 0;
    transition: 0.3s;
}

.navbar.fixed .menu-toggle span {
    background-color: black;
}

/* 移动端响应式设计 */
@media (max-width: 768px) {
    .navbar {
        padding: 5px 15px;
    }
    
    .navbar ul {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        background-color: rgba(0, 0, 0, 0.95);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        padding: 20px 0;
        backdrop-filter: blur(10px);
        margin: 0;
    }
    
    .navbar ul.active {
        left: 0;
    }
    
    .navbar ul li {
        margin: 15px 0;
    }
    
    .navbar ul li a {
        font-size: 18px;
        padding: 10px 0;
        display: block;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    /* 汉堡菜单动画 */
    .menu-toggle.active span:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }
    
    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .menu-toggle.active span:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }
}

@media (max-width: 480px) {
    .navbar {
        padding: 5px 10px;
    }
    
    .navbar ul li a {
        font-size: 16px;
    }
    
    .menu-toggle span {
        width: 20px;
        height: 2px;
    }
}