/* ========================================
   头部导航样式
   ======================================== */

/* 头部容器 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: #fff;
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.header-inner {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.logo-icon {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-dark), var(--secondary-blue));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: bold;
    font-size: 20px;
}

.logo-icon-img {
    width: 50px;
    height: 50px;
    object-fit: contain;
    border-radius: var(--radius-sm);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-text .cn {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-title);
    line-height: 1.2;
}

.logo-text .en {
    font-size: 11px;
    color: var(--text-muted);
    font-family: var(--font-en);
    letter-spacing: 0.5px;
}

/* 导航菜单 */
.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--space-xxl);
    margin-left: auto;
    margin-right: var(--space-xl);
}

.nav-item {
    position: relative;
}

.nav-link {
    display: block;
    padding: var(--space-sm) 0;
    font-size: var(--fs-body);
    color: var(--text-body);
    font-weight: 500;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-red);
    transition: width var(--transition-normal);
}

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

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* 联系电话 */
.header-contact {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.phone-number {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    color: var(--primary-dark);
    font-weight: 700;
    font-size: var(--fs-body);
}

.phone-number::before {
    content: '📞';
    font-size: 16px;
}

/* 语言切换器 */
.lang-switcher {
    position: relative;
    margin-left: var(--space-md);
    margin-right: 0;
}

.lang-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    padding: 8px 16px;
    background-color: var(--primary-dark);
    border: 1px solid var(--primary-dark);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    transition: all var(--transition-fast);
    min-width: 60px;
}

.lang-btn:hover {
    background-color: var(--primary-red);
    border-color: var(--primary-red);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.lang-arrow {
    font-size: 10px;
    transition: transform var(--transition-fast);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 4px;
    background-color: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
    min-width: 100px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-fast);
    z-index: 1002;
}

.lang-dropdown.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-option {
    display: block;
    padding: 10px 16px;
    font-size: 14px;
    color: var(--text-body);
    text-decoration: none;
    transition: background-color var(--transition-fast);
}

.lang-option:hover {
    background-color: var(--bg-light);
}

.lang-option.active {
    background-color: var(--primary-dark);
    color: #fff;
}

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 28px;
    height: 20px;
    cursor: pointer;
    z-index: 1001;
}

.menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--text-title);
    transition: all var(--transition-fast);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

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

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* 移动端导航 */
@media (max-width: 1024px) {
    .menu-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background-color: #fff;
        flex-direction: column;
        padding: var(--space-lg);
        gap: 0;
        margin-left: 0;
        margin-right: 0;
        box-shadow: var(--shadow-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-normal);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-item {
        width: 100%;
        border-bottom: 1px solid var(--border-color);
    }
    
    .nav-item:last-child {
        border-bottom: none;
    }
    
    .nav-link {
        padding: var(--space-md) 0;
    }
    
    .nav-link::after {
        display: none;
    }
    
    .header-contact {
        display: none;
    }
    
    .lang-switcher {
        margin-left: auto;
        margin-right: var(--space-md);
    }
    
    .lang-btn {
        padding: 6px 12px;
        font-size: 13px;
        min-width: 50px;
    }
}

@media (max-width: 768px) {
    .header {
        height: var(--header-height-mobile);
    }
    
    .logo-icon {
        width: 40px;
        height: 40px;
        font-size: 16px;
    }
    
    .logo-text .cn {
        font-size: 16px;
    }
    
    .logo-text .en {
        font-size: 10px;
    }
    
    .nav-menu {
        top: var(--header-height-mobile);
    }
}