/* 导航栏 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    z-index: 1000;
    transition: all 0.3s var(--ease-smooth);
    padding: 0;
    background: var(--color-pure-white);
}

.header.scrolled {
    background: var(--color-pure-white);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.header-container {
    position: relative;
    width: 100%;
    height: 100%;
    background: transparent;
}

.header-left {
    position: absolute;
    left: 0;
    top: 0;
    width: 200px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
}

.header-center {
    position: absolute;
    left: 200px;
    top: 0;
    width: 300px;
    height: 100%;
    display: flex;
    align-items: center;
}

.header-center nav {
    height: 100%;
    display: flex;
    align-items: center;
}

.header-right {
    display: none; /* 暂时隐藏右侧按钮 */
}

.logo {
    color: var(--color-light-gray);
    text-decoration: none;
    font-size: 14px;
    font-weight: 400;
    transition: all 0.3s ease;
    padding: 0;
    border-radius: 0;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
    cursor: pointer;
}

/* Apply Chinese font to the logo when it contains Chinese text */
.logo.show-chinese {
    font-family: 'Noto Serif SC', serif;
}

.logo:hover {
    background: var(--color-primary-blue);
    color: var(--color-pure-white);
    transform: translateY(-2px);
}

/* 语言切换弹窗 */
.language-tooltip {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    height: 50%;
    background: var(--color-pure-white);
    color: var(--color-pure-black);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 400;
    opacity: 0;
    transform: translateY(-100%);
    transition: all 0.3s ease;
    pointer-events: none;
    z-index: 1000;
    overflow: hidden;
}

.logo:hover .language-tooltip {
    opacity: 1;
    transform: translateY(0);
}

.nav-menu {
    display: flex;
    margin: 0;
    padding: 0;
    list-style: none;
    height: var(--header-height);
    width: 100%;
}

.nav-menu li {
    width: 100px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.nav-menu li:nth-child(1) {
    /* Work: 200-300px */
}

.nav-menu li:nth-child(2) {
    /* About: 300-400px */
}

.nav-menu li:nth-child(3) {
    /* Services: 400-500px */
}

.nav-link {
    color: var(--color-light-gray);
    text-decoration: none;
    font-size: 14px;
    font-weight: 400;
    transition: all 0.3s ease;
    padding: 0;
    border-radius: 0;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
}

.nav-link:hover {
    background: var(--color-primary-blue);
    color: var(--color-pure-white);
    transform: translateY(-2px);
}

/* 下拉菜单容器 */
.dropdown-overlay {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100vw;
    height: calc(100vh - var(--header-height));
    background: var(--color-primary-blue);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 999;
    transform: translateY(-100%);
    transition: transform 0.5s var(--ease-smooth);
    pointer-events: none;
    margin-top: 0;
    border-top: none;
}

.dropdown-overlay.active {
    transform: translateY(0);
    pointer-events: auto;
}

.dropdown-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 80px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.dropdown-placeholder {
    text-align: center;
    color: var(--color-light-gray);
}

.dropdown-placeholder h2 {
    font-size: 48px;
    font-weight: 300;
    margin-bottom: 20px;
    color: var(--color-pure-white);
}

.dropdown-placeholder p {
    font-size: 18px;
    opacity: 0.7;
}

.cta-button {
    color: var(--color-light-gray);
    text-decoration: none;
    font-size: 14px;
    font-weight: 400;
    transition: all 0.3s ease;
    padding: 0 20px;
    border-radius: 0;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    background: transparent;
    border: none;
}

.cta-button:hover {
    background: #3398fe;
    color: var(--color-pure-white);
    transform: translateY(-2px);
}