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

/* ========== 主头部 ========== */
.main-header {
    position: relative;
    z-index: 1000;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    height: var(--header-height);
    margin-bottom: 0;
}

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

/* Logo区域 */
.header-logo {
    display: flex;
    align-items: center;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.header-logo:hover {
    color: var(--primary-color);
}

/* 搜索区域 */
.header-search {
    flex: 1;
    max-width: 500px;
    margin: 0 var(--spacing-xl);
    position: relative;
}

.search-form {
    width: 100%;
}

.search-input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.search-input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md) var(--spacing-sm) 2.5rem;
    font-size: var(--font-size-base);
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    background-color: var(--bg-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.search-input::placeholder {
    color: var(--text-tertiary);
}

.search-icon {
    position: absolute;
    left: var(--spacing-md);
    width: 18px;
    height: 18px;
    color: var(--text-tertiary);
    pointer-events: none;
    z-index: 1;
}

.search-icon-mobile {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    padding: 0;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    transition: color var(--transition-fast);
}

.search-icon-mobile:hover {
    color: var(--primary-color);
}

/* 搜索覆盖层 */
.search-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 2000;
    animation: fadeIn var(--transition-base);
}

.search-overlay.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.search-modal {
    width: 90%;
    max-width: 500px;
    background-color: var(--bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    z-index: 2001;
    animation: slideDown var(--transition-base);
    overflow: hidden;
}

.search-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-light);
}

.search-modal-header h3 {
    margin: 0;
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
}

.search-close-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    padding: 0;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.search-close-btn:hover {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
}

.search-modal-body {
    padding: var(--spacing-lg);
}

.search-modal-input {
    width: 100%;
    padding: var(--spacing-md);
    font-size: var(--font-size-base);
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.search-modal-input:focus {
    outline: none;
    border-color: var(--primary-color);
    background-color: var(--bg-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* ========== 导航菜单 ========== */
.main-nav {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    height: var(--nav-height);
    position: relative;
    z-index: 999;
    margin-top: 0;
}

.nav-list {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    list-style: none;
    gap: 0;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
}

.nav-link {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    padding: 0 var(--spacing-md);
    font-size: var(--font-size-base);
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    border-bottom: 2px solid transparent;
}

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

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

/* ========== 移动端头部 ========== */
@media (max-width: 768px) {
    .main-header {
        height: 56px;
    }
    
    .header-logo {
        font-size: var(--font-size-lg);
    }
    
    .header-search {
        display: none;
    }
    
    .search-icon-mobile {
        display: block;
        width: 24px;
        height: 24px;
        color: var(--text-primary);
        cursor: pointer;
    }
    
    .main-nav {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
    }
    
    .main-nav::-webkit-scrollbar {
        display: none;
    }
    
    .nav-list {
        gap: 0;
        padding: 0 var(--spacing-sm);
    }
    
    .nav-link {
        font-size: var(--font-size-sm);
        padding: 0 var(--spacing-sm);
        white-space: nowrap;
    }
    
    .search-modal {
        width: 95%;
        padding: var(--spacing-lg);
    }
}