/* Header 基础样式 */
.header {
    background: white;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    height: 32px;
    position: relative;
    padding: 0 10px;
}

.logo img {
    height: 32px;
    width: 140px; /* 适应新的logo宽度 */
    transition: all 0.3s ease;
}

.logo-white {
    opacity: 0;
    position: absolute;
    left: 10px;
    top: 50%;
    transform: translateY(-50%);
}

.logo-dark {
    opacity: 1;
}

/* 添加hover效果 */
.logo:hover img {
    transform: translateY(-1px);
}

/* 透明状态下的 logo 显示 */
header.transparent .logo-white {
    opacity: 1;
}

header.transparent .logo-dark {
    opacity: 0;
}

/* 滚动状态下的 logo 显示 */
header.scrolled .logo-white {
    opacity: 0;
}

header.scrolled .logo-dark {
    opacity: 1;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.nav-link.active {
    color: var(--primary-color);
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1000;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-color);
    margin: 5px 0;
    transition: all 0.3s ease;
    transform-origin: center;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
        position: relative;
    }

    .nav-menu {
        display: none;
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem 0;
        gap: 1rem;
        box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
        text-align: center;
        z-index: 999;
    }

    .nav-menu.active {
        display: flex !important;
    }

    /* 汉堡菜单动画 */
    .menu-toggle.active span:first-child {
        transform: translateY(7px) rotate(45deg);
    }

    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .menu-toggle.active span:last-child {
        transform: translateY(-7px) rotate(-45deg);
    }

    .logo {
        height: 28px;
        padding: 0 5px;
    }
    
    .logo img {
        height: 28px;
        width: 123px; /* 按比例缩小 */
    }
    
    .logo-white {
        left: 5px;
    }
}

header {
    transition: all 0.3s ease;
    position: fixed;
    width: 100%;
    z-index: 1000;
    height: 64px;
    background: rgba(255, 255, 255, 0);
    backdrop-filter: blur(0);
}

header.transparent {
    background: transparent;
    box-shadow: none;
}

header.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

header.transparent .logo,
header.transparent .nav-link {
    color: white;
    transition: color 0.3s ease;
}

header.scrolled .logo,
header.scrolled .nav-link {
    color: var(--text-color);
}

/* 移动端样式调整 */
@media (max-width: 768px) {
    header.transparent .nav-menu {
        background: rgba(0, 0, 0, 0.8);
        backdrop-filter: blur(10px);
    }
    
    header.scrolled .nav-menu {
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: blur(10px);
    }
    
    header.scrolled .nav-link {
        color: var(--text-color);
    }
    
    header.scrolled .menu-toggle span {
        background: var(--text-color);
    }
}