/* float-nav-fixed.css - 优化常显式悬浮导航 */
#float-vertical-nav {
    position: fixed;
    top: 50%;
    left: 20px;
    transform: translateY(-50%);
    z-index: 9999;
    background: linear-gradient(135deg, #ffffff 0%, #f7f9fc 100%);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: 16px;
    box-shadow: 
        0 16px 48px rgba(0, 0, 0, 0.12),
        0 8px 24px rgba(0, 0, 0, 0.08),
        inset 0 1px 0 rgba(255, 255, 255, 0.9),
        0 0 0 1px rgba(255, 255, 255, 0.4);
    border: 1px solid rgba(226, 232, 240, 0.9);
    padding: 20px 16px;
    transition: all 0.3s ease;
    max-height: 80vh;
    overflow-y: auto;
    min-width: 200px;
    width: auto;
    display: block !important;
    visibility: visible !important;
    opacity: 1 !important;
}

.float-nav-item {
    display: flex;
    align-items: center;
    padding: 14px 18px;
    margin: 6px 0;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    color: #334155;
    text-decoration: none;
    position: relative;
    white-space: nowrap;
    overflow: hidden;
    font-size: 14px;
    font-weight: 600;
    background: transparent;
    border: none;
    width: 100%;
    text-align: left;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    letter-spacing: -0.01em;
}

.float-nav-number {
    width: 28px;
    height: 28px;
    min-width: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 700;
    color: #64748b;
    background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
    border-radius: 8px;
    transition: all 0.3s ease;
    margin-right: 14px;
    box-shadow: 
        0 2px 8px rgba(0, 0, 0, 0.04),
        inset 0 1px 0 rgba(255, 255, 255, 0.8);
    border: 1px solid rgba(226, 232, 240, 0.8);
}

.float-nav-text {
    opacity: 1;
    max-width: none;
    overflow: hidden;
    transition: all 0.3s ease;
    font-size: 14px;
    font-weight: 600;
    color: #475569;
    white-space: nowrap;
    flex: 1;
    padding-right: 4px;
}

.float-nav-item:hover {
    background: linear-gradient(90deg, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0.05) 100%);
    color: #1e40af;
    transform: translateX(4px);
    box-shadow: 
        inset 0 0 0 1px rgba(59, 130, 246, 0.2),
        0 4px 16px rgba(59, 130, 246, 0.1);
}

.float-nav-item:hover .float-nav-number {
    background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
    color: white;
    transform: scale(1.08);
    box-shadow: 
        0 4px 12px rgba(59, 130, 246, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.4);
    border-color: rgba(59, 130, 246, 0.3);
}

.float-nav-item.active {
    background: linear-gradient(90deg, #3b82f6 0%, #2563eb 100%);
    color: white;
    transform: translateX(4px);
    box-shadow: 
        0 6px 24px rgba(59, 130, 246, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.float-nav-item.active .float-nav-number {
    background: rgba(255, 255, 255, 0.3);
    color: white;
    transform: scale(1.1);
    box-shadow: 
        0 4px 12px rgba(255, 255, 255, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.4);
    border-color: rgba(255, 255, 255, 0.3);
}

.float-nav-item.active .float-nav-text {
    color: white;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
    font-weight: 700;
}

#nav-back-to-top.float-nav-item {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border: 1px solid rgba(206, 212, 218, 0.5);
    margin-top: 12px;
}

#nav-back-to-top.float-nav-item .float-nav-number {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: white;
}

#nav-back-to-top.float-nav-item:hover {
    background: linear-gradient(90deg, rgba(16, 185, 129, 0.15) 0%, rgba(16, 185, 129, 0.08) 100%);
    border-color: rgba(16, 185, 129, 0.3);
    color: #065f46;
}

#nav-back-to-top.float-nav-item:hover .float-nav-number {
    background: linear-gradient(135deg, #059669 0%, #047857 100%);
    transform: scale(1.08);
}

#nav-back-to-top.float-nav-item.active {
    background: linear-gradient(90deg, #10b981 0%, #059669 100%);
    color: white;
    border-color: transparent;
}

#nav-back-to-top.float-nav-item.active .float-nav-number {
    background: rgba(255, 255, 255, 0.3);
    color: white;
}

.float-nav-separator {
    height: 1px;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(203, 213, 225, 0.8), 
        transparent);
    margin: 14px 18px;
}

#float-vertical-nav::-webkit-scrollbar {
    width: 6px;
}

#float-vertical-nav::-webkit-scrollbar-track {
    background: rgba(241, 245, 249, 0.8);
    border-radius: 3px;
}

#float-vertical-nav::-webkit-scrollbar-thumb {
    background: linear-gradient(to bottom, #94a3b8, #64748b);
    border-radius: 3px;
}

#float-vertical-nav::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(to bottom, #64748b, #475569);
}

@media (max-width: 1600px) {
    #float-vertical-nav {
        left: 16px;
        min-width: 180px;
        padding: 18px 14px;
    }
    
    .float-nav-item {
        padding: 12px 16px;
        font-size: 13px;
    }
    
    .float-nav-number {
        width: 26px;
        height: 26px;
        font-size: 11px;
        margin-right: 12px;
    }
}

@media (max-width: 1400px) {
    #float-vertical-nav {
        left: 12px;
        min-width: 160px;
        padding: 16px 12px;
    }
    
    .float-nav-item {
        padding: 10px 14px;
    }
    
    .float-nav-number {
        width: 24px;
        height: 24px;
        margin-right: 10px;
    }
}

@media (max-width: 1200px) {
    #float-vertical-nav {
        left: 8px;
        min-width: 150px;
        padding: 14px 10px;
    }
    
    .float-nav-item {
        padding: 8px 12px;
        border-radius: 10px;
    }
}

@media (max-width: 768px) {
    #float-vertical-nav {
        display: none !important;
    }
}