/* ==========================================
   头部导航 - Header & Navigation
   包括桌面端导航和移动端汉堡菜单
   ========================================== */

header {
    background-color: #ffffff;
    padding: 20px 60px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
    z-index: 1001;
}

.logo img {
    height: 40px;
    width: auto;
}

.logo-text {
    font-size: 24px;
    font-weight: 600;
    color: #265965;
}

nav {
    display: flex;
    align-items: center;
}

.nav-menu {
    display: flex;
    gap: 50px;
    list-style: none;
    align-items: center;
}

.nav-menu li a {
    text-decoration: none;
    color: #333;
    font-size: 16px;
    font-weight: 500;
    transition: color 0.3s ease;
    white-space: nowrap;
}

.nav-menu li a:hover {
    color: #5cb85c;
}

.nav-menu li a.active {
    color: #a8c84e;
    font-weight: 600;
    position: relative;
}

.nav-menu li a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: #a8c84e;
}

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

.menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

/* 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);
}

/* 响应式设计 */
@media (max-width: 768px) {
    header {
        padding: 15px 20px;
    }

    .logo img {
        height: 32px;
    }

    nav {
        position: absolute;
        right: 0;
        top: 0;
        height: 100%;
        display: flex;
        align-items: center;
    }

    .menu-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 70%;
        max-width: 300px;
        background-color: #ffffff;
        flex-direction: column;
        justify-content: flex-start;
        align-items: flex-start;
        padding: 80px 30px 30px;
        gap: 30px;
        box-shadow: -2px 0 10px rgba(0, 0, 0, 0.1);
        transition: right 0.3s ease;
    }

    .nav-menu.active {
        right: 0;
    }

    .nav-menu li {
        width: 100%;
    }

    .nav-menu li a {
        display: block;
        padding: 10px 0;
        font-size: 18px;
        border-bottom: 1px solid #f0f0f0;
    }

    .nav-menu li a.active::after {
        display: none;
    }

    .nav-menu li a.active {
        color: #a8c84e;
        background-color: #f8f9fa;
        padding-left: 10px;
        border-left: 3px solid #a8c84e;
    }
}