/* ==================== 
   公共组件样式
   ==================== */

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

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

.nav-container {
    max-width: var(--container-xl);
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--primary-blue);
    text-decoration: none;
}

.logo-icon {
    font-size: var(--text-2xl);
    color: var(--accent-cyan);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
    padding: var(--spacing-sm);
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--primary-blue);
    transition: all var(--transition-fast);
}

.nav-menu {
    display: flex;
    gap: var(--spacing-xl);
}

.nav-link {
    font-size: var(--text-base);
    font-weight: 500;
    color: var(--text-secondary);
    padding: var(--spacing-sm) 0;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-cyan);
    transition: width var(--transition-base);
}

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

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

/* ==================== 页脚 ==================== */
.footer {
    background: var(--primary-blue-dark);
    color: var(--text-light);
    padding: var(--spacing-2xl) 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: var(--spacing-xl);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--text-xl);
    font-weight: 700;
}

.footer-desc {
    margin-top: var(--spacing-sm);
    opacity: 0.7;
    font-size: var(--text-sm);
}

.footer-links {
    display: flex;
    gap: var(--spacing-xl);
}

.footer-links a {
    opacity: 0.7;
    transition: opacity var(--transition-fast);
}

.footer-links a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-xl);
    opacity: 0.5;
    font-size: var(--text-sm);
}

/* ==================== 页面标题横幅 ==================== */
.page-banner {
    background: linear-gradient(135deg, var(--primary-blue-dark) 0%, var(--primary-blue) 50%, var(--primary-blue-light) 100%);
    padding: 120px 0 60px;
    text-align: center;
    color: var(--text-light);
    position: relative;
    overflow: hidden;
}

.page-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    opacity: 0.3;
}

.page-banner .container {
    position: relative;
    z-index: 1;
}

.page-title {
    font-family: var(--font-heading);
    font-size: var(--text-5xl);
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.page-subtitle {
    font-size: var(--text-xl);
    opacity: 0.8;
}

.breadcrumb {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-lg);
    font-size: var(--text-sm);
    opacity: 0.7;
}

.breadcrumb a {
    color: var(--text-light);
    opacity: 0.8;
}

.breadcrumb a:hover {
    opacity: 1;
}

.breadcrumb span {
    opacity: 0.5;
}

/* ==================== 返回顶部按钮 ==================== */
.back-to-top {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    width: 48px;
    height: 48px;
    background: var(--primary-blue);
    color: var(--text-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-xl);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 999;
    cursor: pointer;
    border: none;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--accent-cyan);
    transform: translateY(-4px);
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--bg-primary);
        flex-direction: column;
        padding: var(--spacing-xl);
        gap: var(--spacing-md);
        box-shadow: var(--shadow-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-link {
        padding: var(--spacing-md);
        border-bottom: 1px solid var(--border-light);
    }
}

@media (max-width: 768px) {
    .page-title {
        font-size: var(--text-3xl);
    }
    
    .page-subtitle {
        font-size: var(--text-lg);
    }
    
    .footer-content {
        flex-direction: column;
        gap: var(--spacing-xl);
        text-align: center;
    }
    
    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}