body {
    background: linear-gradient(to bottom, #003366, #0066CC);
    min-height: 100vh;
    overflow-x: hidden;
}
.hide{
    display:none;
}
.fish {
    position: absolute;
    width: 50px;
    height: 50px;
    background-size: contain;
    background-repeat: no-repeat;
    animation: swim 10s linear infinite;
}

@keyframes swim {
    0% {
        transform: translateX(-100px) translateY(0) rotateY(0deg);
    }
    49% {
        transform: translateX(calc(100vw + 100px)) translateY(0) rotateY(0deg);
    }
    50% {
        transform: translateX(calc(100vw + 100px)) translateY(0) rotateY(180deg);
    }
    99% {
        transform: translateX(-100px) translateY(0) rotateY(180deg);
    }
    100% {
        transform: translateX(-100px) translateY(0) rotateY(0deg);
    }
}

.bubble {
    position: absolute;
    background-color: rgba(255, 255, 255, 0.7);
    border-radius: 50%;
    animation: rise 3s ease-in infinite;
}

@keyframes rise {
    0% {
        transform: translateY(0) scale(0);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    100% {
        transform: translateY(-100vh) scale(1);
        opacity: 0;
    }
}

/* 浮动下载按钮样式保持不变，使用已有的 animate-float */



.download-button {
    position: relative;
    overflow: hidden;
}

.download-button::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background-color: rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.download-button:active::after {
    width: 300px;
    height: 300px;
}

.nav-link {
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #FFD700;
    transition: width 0.3s ease;
}

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

.feature-card {
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.news-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.news-card:hover .news-image {
    transform: scale(1.05);
}

.news-image {
    transition: transform 0.5s ease;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    overflow: auto;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 700px;
    border-radius: 10px;
    animation: slideIn 0.4s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.close {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover,
.close:focus {
    color: black;
    text-decoration: none;
}

/* 页面过渡动画 */
.page-transition {
    transition: filter 0.5s ease, opacity 0.5s ease;
    filter: blur(5px);
    opacity: 0.8;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-text, .hero-image {
        width: 100%;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    #floating-download {
        bottom: 20px;
        right: 20px;
    }
    
    #scroll-to-download {
        padding: 2px 12px;
        font-size: 14px;
    }
}