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

body {
    font-family: 'Noto Sans SC', sans-serif;
    overflow-x: hidden;
}

/* 头部毛玻璃效果 */
.header {
    background-color: rgba(0, 0, 0, 0.15);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

/* 顶部导航链接 */
.nav-link {
    color: #fff;
    font-size: 12px;
    font-weight: 500;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 1px;
    background: #fff;
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    transform: scaleX(1);
}

/* 汉堡菜单动画 */
.hamburger-line {
    transition: all 0.3s ease;
}

.hamburger.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.hamburger.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* 移动端菜单 */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.45);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 100;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s ease;
}

.mobile-menu.active {
    opacity: 1;
    visibility: visible;
}

.mobile-menu-content {
    transform: translateY(20px);
    transition: transform 0.4s ease;
}

.mobile-menu.active .mobile-menu-content {
    transform: translateY(0);
}

/* 子菜单 */
.submenu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    border-left: 1px solid #fff;
}

.submenu.active {
    max-height: 200px;
}

/* Hero区域 */
.hero-section {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: linear-gradient(to bottom, #f5f5f5 0%, #e0e0e0 30%, #4a4a4a 70%, #2a2a2a 100%);
}

.hero-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 70%;
    background: url('https://images.unsplash.com/photo-1464822759023-fed622ff2c3b?w=1200') center bottom/cover no-repeat;
    filter: grayscale(100%);
}

/* 移动端菜单项样式 */
.menu-item {
    color: rgb(212, 212, 213);
    font-size: 14px;
    font-weight: 500;
}

.menu-item:hover {
    color: #fff;
}

/* 子菜单项样式 */
.submenu-item {
    color: rgb(212, 212, 213);
    font-size: 14px;
    font-weight: 500;
}

.submenu-item:hover {
    color: #fff;
}

/* 滚动动画 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}