/* ===== 高级页脚设计系统 ===== */
:root {
    /* 页脚专用色彩系统 */
    --footer-bg-primary: #000000;
    --footer-bg-secondary: #0a0a0a;
    --footer-bg-tertiary: #1a1a1a;
    --footer-text-primary: #ffffff;
    --footer-text-secondary: #cccccc;
    --footer-text-muted: #999999;
    --footer-text-light: #666666;
    
    /* 页脚渐变系统 */
    --footer-gradient-primary: linear-gradient(135deg, #000000 0%, #0a0a0a 25%, #1a1a1a 50%, #2a2a2a 75%, #3a3a3a 100%);
    --footer-gradient-overlay: linear-gradient(135deg, rgba(0,0,0,0.95) 0%, rgba(10,10,10,0.9) 100%);
    --footer-gradient-wave: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 50%, #3a3a3a 100%);
    
    /* 页脚阴影系统 */
    --footer-shadow-sm: 0 -2px 10px rgba(0, 0, 0, 0.1);
    --footer-shadow-md: 0 -4px 20px rgba(0, 0, 0, 0.15);
    --footer-shadow-lg: 0 -8px 40px rgba(0, 0, 0, 0.2);
    
    /* 页脚动画系统 */
    --footer-transition-fast: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --footer-transition-normal: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    --footer-ease-out-back: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ===== 页脚主容器 ===== */
.footer {
    background: var(--footer-gradient-primary);
    color: var(--footer-text-primary);
    position: relative;
    margin-top: 5rem;
    overflow: hidden;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--footer-gradient-overlay);
    z-index: 1;
}

/* ===== 波浪装饰 ===== */
.tech-footer-wave {
    position: relative;
    z-index: 2;
    height: 100px;
    overflow: hidden;
}

.tech-footer-wave svg {
    width: 100%;
    height: 100%;
    display: block;
}

.tech-footer-wave path {
    fill: var(--footer-bg-tertiary) !important;
    animation: waveFlow 8s ease-in-out infinite;
}

@keyframes waveFlow {
    0%, 100% { d: path("M0,32L48,37.3C96,43,192,53,288,58.7C384,64,480,64,576,58.7C672,53,768,43,864,48C960,53,1056,75,1152,74.7C1248,75,1344,53,1392,42.7L1440,32L1440,100L1392,100C1344,100,1248,100,1152,100C1056,100,960,100,864,100C768,100,672,100,576,100C480,100,384,100,288,100C192,100,96,100,48,100L0,100Z"); }
    50% { d: path("M0,42L48,47.3C96,53,192,63,288,68.7C384,74,480,74,576,68.7C672,63,768,53,864,58C960,63,1056,85,1152,84.7C1248,85,1344,63,1392,52.7L1440,42L1440,100L1392,100C1344,100,1248,100,1152,100C1056,100,960,100,864,100C768,100,672,100,576,100C480,100,384,100,288,100C192,100,96,100,48,100L0,100Z"); }
}

/* ===== 页脚主要内容 ===== */
.footer-main {
    position: relative;
    z-index: 3;
    background: var(--footer-bg-primary);
    padding: 4rem 0 2rem 0;
}

/* ===== 页脚品牌区域 ===== */
.footer-brand {
    margin-bottom: 2rem;
}

.footer-brand img {
    height: 48px;
    filter: brightness(1.1) contrast(1.1);
    transition: var(--footer-transition-fast);
}

.footer-brand img:hover {
    filter: brightness(1.3) contrast(1.2);
    transform: scale(1.05);
}

.tech-logo-glow {
    filter: drop-shadow(0 0 20px rgba(255, 255, 255, 0.3));
    animation: logoGlow 3s ease-in-out infinite alternate;
}

@keyframes logoGlow {
    from { filter: drop-shadow(0 0 20px rgba(255, 255, 255, 0.3)); }
    to { filter: drop-shadow(0 0 30px rgba(255, 255, 255, 0.5)); }
}

.footer-description {
    color: var(--footer-text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 2rem;
    max-width: 300px;
}

/* ===== 社交链接 ===== */
.social-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.1);
    color: var(--footer-text-secondary);
    border-radius: 50%;
    text-decoration: none;
    transition: var(--footer-transition-fast);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.social-icon::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.2), rgba(255,255,255,0.1));
    opacity: 0;
    transition: var(--footer-transition-fast);
}

.social-icon:hover {
    color: var(--footer-text-primary);
    transform: translateY(-3px) scale(1.1);
    box-shadow: 0 8px 25px rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.3);
}

.social-icon:hover::before {
    opacity: 1;
}

/* ===== 页脚标题 ===== */
.footer-title {
    color: var(--footer-text-primary);
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.footer-title-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: linear-gradient(135deg, #ffffff 0%, #cccccc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ===== 页脚链接 ===== */
.footer-links {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: var(--footer-text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--footer-transition-fast);
    position: relative;
    display: inline-block;
    padding: 0.25rem 0;
}

.footer-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--footer-text-secondary);
    transition: width var(--footer-transition-fast);
}

.footer-links a:hover {
    color: var(--footer-text-secondary);
    transform: translateX(4px);
}

.footer-links a:hover::after {
    width: 100%;
}

/* ===== 页脚底部 ===== */
.footer-bottom {
    background: var(--footer-bg-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    z-index: 3;
    padding: 1.5rem 0;
}

.footer-bottom p {
    margin: 0;
    color: var(--footer-text-muted);
    font-size: 0.875rem;
}

.beian-link {
    color: var(--footer-text-muted) !important;
    transition: var(--footer-transition-fast);
}

.beian-link:hover {
    color: var(--footer-text-secondary) !important;
}

/* ===== 响应式设计 ===== */
@media (max-width: 768px) {
    .footer-main {
        padding: 3rem 0 1.5rem 0;
    }
    
    .footer-brand {
        text-align: center;
        margin-bottom: 2rem;
    }
    
    .footer-description {
        text-align: center;
        max-width: none;
        margin: 0 auto 2rem auto;
    }
    
    .social-links {
        justify-content: center;
        margin-bottom: 2rem;
    }
    
    .footer-title {
        text-align: center;
        justify-content: center;
        margin-bottom: 1rem;
    }
    
    .footer-links {
        text-align: center;
    }
    
    .footer-bottom {
        text-align: center;
    }
}

/* ===== 装饰性动画 ===== */
@keyframes footerFloat {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-5px); }
}

.footer-main::after {
    content: '';
    position: absolute;
    top: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    animation: footerShimmer 3s ease-in-out infinite;
}

@keyframes footerShimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}