/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 头部样式 */
.header {
    background: linear-gradient(90deg, #6a11cb 0%, #2575fc 100%);
    color: white;
    padding: 20px 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    position: relative;
    overflow: hidden;
}

.header::before {
    content: "";
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
    background-size: 30px 30px;
    animation: moveBackground 20s linear infinite;
    z-index: 0;
}

@keyframes moveBackground {
    0% { transform: translate(0, 0); }
    100% { transform: translate(30px, 30px); }
}

.header .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    z-index: 1;
}

.logo {
    text-align: center;
    margin-bottom: 20px;
}

.logo h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.logo h1 a {
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.logo h1 a:hover {
    color: #ffeb3b;
    transform: scale(1.05);
}

.tagline {
    font-size: 1.1rem;
    opacity: 0.9;
}

.search-box {
    width: 100%;
    max-width: 600px;
}

.search-box form {
    display: flex;
    border-radius: 50px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.search-input {
    flex-grow: 1;
    padding: 15px 20px;
    border: none;
    font-size: 1rem;
    outline: none;
}

.search-btn {
    background: #ff5722;
    color: white;
    border: none;
    padding: 0 30px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: bold;
    transition: all 0.3s ease;
}

.search-btn:hover {
    background: #ff7043;
}

/* 主要内容区 */
.main-content {
    padding: 40px 0;
}

.high-density-section {
    background: white;
    border-radius: 15px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    animation: fadeIn 1s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.high-density-section h2 {
    color: #2575fc;
    margin-bottom: 20px;
    font-size: 1.8rem;
    border-bottom: 2px solid #6a11cb;
    padding-bottom: 10px;
}

.keywords-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 25px;
    justify-content: center;
}

.keyword-high {
    background: linear-gradient(45deg, #6a11cb, #2575fc);
    color: white;
    padding: 8px 15px;
    border-radius: 50px;
    font-weight: bold;
    box-shadow: 0 3px 8px rgba(106, 17, 203, 0.3);
    transition: all 0.3s ease;
    animation: float 3s ease-in-out infinite;
    animation-delay: calc(var(--i) * 0.1s);
}

.keyword-high:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(106, 17, 203, 0.4);
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.density-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #444;
}

/* 图片展示区 */
.gallery-section {
    background: white;
    border-radius: 15px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
}

.gallery-section h2 {
    color: #2575fc;
    margin-bottom: 20px;
    font-size: 1.8rem;
    border-bottom: 2px solid #6a11cb;
    padding-bottom: 10px;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 25px;
    margin-bottom: 30px;
}

.gallery-item {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.4s ease;
    background: white;
}

.gallery-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.gallery-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    display: block;
    transition: transform 0.5s ease;
}

.gallery-item:hover img {
    transform: scale(1.05);
}

.img-desc {
    padding: 15px;
    text-align: center;
    font-weight: bold;
    color: #333;
    background: #f9f9f9;
}

.keywords-list {
    background: #f0f7ff;
    padding: 20px;
    border-radius: 10px;
    border-left: 5px solid #2575fc;
}

.keywords-list p {
    font-size: 1rem;
    line-height: 1.6;
}

/* 关键词堆砌区域 */
.keyword-stuffing {
    background: white;
    border-radius: 15px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
}

.keyword-stuffing h2 {
    color: #2575fc;
    margin-bottom: 20px;
    font-size: 1.8rem;
    border-bottom: 2px solid #6a11cb;
    padding-bottom: 10px;
}

.keyword-blocks {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.keyword-block {
    background: #f9f9f9;
    padding: 20px;
    border-radius: 10px;
    border: 1px solid #e0e0e0;
    transition: all 0.3s ease;
}

.keyword-block:hover {
    background: #f0f7ff;
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(37, 117, 252, 0.1);
}

.keyword-block h3 {
    color: #6a11cb;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.keyword-block p {
    font-size: 0.95rem;
    line-height: 1.5;
    color: #555;
}

/* 页脚 */
.footer {
    background: linear-gradient(90deg, #2c3e50 0%, #4a6491 100%);
    color: white;
    padding: 40px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.footer-links h3,
.footer-keywords h3 {
    color: #ffeb3b;
    margin-bottom: 20px;
    font-size: 1.4rem;
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: #ddd;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #ffeb3b;
    padding-left: 5px;
}

.footer-keywords p {
    font-size: 0.9rem;
    line-height: 1.6;
    color: #ccc;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    color: #aaa;
}

.copyright a {
    color: #ffeb3b;
    text-decoration: none;
}

.copyright a:hover {
    text-decoration: underline;
}

/* 隐藏关键词区域（针对SEO优化） */
.hidden-keywords {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .logo h1 {
        font-size: 2rem;
    }
    
    .search-box {
        width: 90%;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
    
    .keyword-blocks {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.6rem;
    }
    
    .tagline {
        font-size: 0.9rem;
    }
    
    .search-box form {
        flex-direction: column;
        border-radius: 10px;
    }
    
    .search-input {
        border-radius: 10px 10px 0 0;
    }
    
    .search-btn {
        border-radius: 0 0 10px 10px;
        padding: 15px;
    }
    
    .gallery-grid {
        grid-template-columns: 1fr;
    }
}