*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family:  'Open Sans', sans-serif;
}


body{
    height: 100vh;
    background-color: rgb(255, 255, 255);

    background-size: cover;
    background-position: center;
}
li{
    list-style: none;
}

a{
    text-decoration: none;
    color: rgb(0, 0, 0);
    font-size: 20px;
    position: relative;

}
a:hover{
    color: orange;
}
.navbar a::after,
.dropdown_menu a::after,
footer a::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: orange;
    transition: width 0.3s ease;
}

.navbar a:hover::after,
.dropdown_menu a:hover::after,
footer a:hover::after {
    width: 100%;
}

/* 仅在导航栏、dropdown_menu 和 footer 内的激活状态的链接样式 */
.navbar a.active,
.dropdown_menu a.active,
footer a.active {
    color: orange;
}

.navbar a.active::after,
.dropdown_menu a.active::after,
footer a.active::after {
    width: 100%;
}

header{
    position: relative;
    padding: 0 2rem;
    
}

.navbar{
    width: 100%;
    height: 80px;
    /* max-width: 1200px; */
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: fixed;
    top: 0;
    z-index: 9999;
    left: 0;
    background-color: rgba(255, 255, 255, 0.8);
    padding: 15px;
}
.navbar .logo a {
    font-style: 1.5rem;
    font-weight: bold;
    max-width: 200px;
}
.navbar .links{
    display: flex;
    gap: 2rem;
    max-width: 800px;
}
.navbar .toggle_btn{
    color: rgb(0, 0, 0);
    font-size: 1.5rem;
    cursor: pointer;
    display: none;
}

.action_btn{
    background-color: orange;
    color: aliceblue;
    padding: 0.5rem 1rem;
    border: none;
    outline: none;
    border-radius: 25px;
    font-size: 1.3rem;
    font-weight: bold;
    cursor: pointer;
}
.action_btn:hover{
    scale: 1.05;
    color: rgb(255, 255, 255);
}
.action_btn:active{
    scale: 0.95;
}
.dropdown_menu{
    display: none;
    position: absolute;
    right: 0;
    top: 60px;
    height: 0;
    width: 300px;
    background: rgba(255, 255,255, 0.1);
    backdrop-filter: blur(15px);
    border-radius: 10px;
    overflow: hidden;
    transition: height .2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: fixed;
    z-index: 99999;
}
.dropdown_menu.open{
    height: 400px;
}
.dropdown_menu li{
    padding: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}
.dropdown_menu .action_btn{
    width: 100%;
    display: flex;
    justify-content: center;

}
@media(max-width:1080px){
    .navbar .links,
    .navbar .action_btn{
        display: none;
    }
    .navbar .toggle_btn{
        display: block;
    }
    .dropdown_menu{
        display: block;
    }
}

@media (max-width: 600px) {
    .navbar{
        height: 60px;
        }
    

}