:root {
    --primary: #0042d1;
    --secondary: #b249db;
    --gradient: linear-gradient(45deg, var(--primary), var(--secondary));
    --dark: #060D1F;
    --dark-gray: #1a1a1f;
    --gray: #2a2a30;
    --light: #292929;
    --light-gray: #4e4d4d;
    --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

body {
    font-family: 'Inter', sans-serif;
    color: var(--light);
    line-height: 1.6;
    overflow-x: hidden;
    overflow-y: scroll;
    position: relative;
    min-height: 100vh;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('../assets/bg6.png');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    z-index: -1;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 1.5rem;
    transition: all 0.3s ease;
    position: absolute;
    top: 1rem;
    left: 2rem;
}

.back-link:hover {
    color: #00FFE1;
    transform: translateX(-5px);
}

/* Header 样式 */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    background: rgb(255, 255, 255);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.main-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 4rem;
}

.logo {
    width: 200px;
    height: 30px;
    background-image: url('../assets/logo/logo4.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: left center;
    display: block;
    transition: var(--transition);
}
.logo2 {
    width: 200px;
    height: 60px;
    background-image: url('../assets/logo/logo3.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: left center;
    display: block;
    transition: var(--transition);
}

.logo:hover {
    opacity: 0.8;
}

.nav-links {
    display: flex;
    gap: 2.5rem;
}

.nav-links a {
    color: var(--light);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient);
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: var(--primary);
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-actions {
    display: flex;
    gap: 1rem;
}

/* 移动端汉堡菜单 */
.hamburger-menu {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1001;
}

.hamburger-line {
    width: 25px;
    height: 3px;
    background: var(--light);
    border-radius: 2px;
    transition: var(--transition);
}

.hamburger-menu.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(7px, 7px);
}

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

.hamburger-menu.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* 移动端导航 */
.mobile-nav {
    display: none;
    position: fixed;
    top: 5rem;
    left: 0;
    width: 100%;
    background: rgba(10, 10, 12, 0.98);
    backdrop-filter: blur(20px);
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    z-index: 999;
}

.mobile-nav.active {
    display: block;
    animation: slideDown 0.3s ease;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.mobile-nav a {
    display: block;
    padding: 1rem;
    color: var(--light);
    font-size: 1.1rem;
    font-weight: 500;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.mobile-nav a:hover {
    color: var(--primary);
    padding-left: 1.5rem;
    background: rgba(0, 209, 178, 0.05);
}

.mobile-nav .btn {
    margin-top: 1rem;
    width: 100%;
    text-align: center;
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links,
    .nav-actions {
        display: none;
    }

    .hamburger-menu {
        display: flex;
    }

    .logo {
        width: 150px;
        height: 30px;
    }

    .main-nav {
        height: 4rem;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .nav-links {
        gap: 1.5rem;
    }

    .logo {
        width: 150px;
        height: 30px;
    }
}

@media (min-width: 1921px) {
    .logo {
        width: 150px;
        height: 30px;
    }

    .main-nav {
        height: 4rem;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    .back-link {
        top: 0.5rem;
        left: 1rem;
    }
}

@media (min-width: 1920px) {
    .container {
        max-width: 1600px;
    }
}