/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* 配色定义：天空蓝(#4A90E2)、素描黑(#2C2C2C)、浅灰(#F5F5F5) */
:root {
    --sky-blue: #4A90E2;
    --sketch-black: #2C2C2C;
    --light-gray: #F5F5F5;
    --white: #FFFFFF;
    --shadow: 0 4px 12px rgba(0,0,0,0.1);
}

body {
    background-color: var(--light-gray);
    color: var(--sketch-black);
    line-height: 1.6;
}

/* 导航栏 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    background: linear-gradient(90deg, var(--sky-blue), #6BA5F5);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow);
}

.navbar .logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--white);
    text-decoration: none;
}

.navbar .nav-links {
    display: flex;
    gap: 2rem;
}

.navbar .nav-links a {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.navbar .nav-links a:hover {
    color: var(--sketch-black);
}

/* 浮动OKX图片 */
.floating-okx {
    position: fixed;
    top: 50%;
    right: 2rem;
    transform: translateY(-50%);
    width: 120px;
    height: auto;
    animation: float 3s ease-in-out infinite;
    z-index: 90;
}

@keyframes float {
    0% { transform: translateY(-50%); }
    50% { transform: translateY(-60%); }
    100% { transform: translateY(-50%); }
}

/* 首页hero区域 */
.hero {
    height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 5%;
    background: linear-gradient(45deg, var(--light-gray), #E8F1FF);
}

.hero-content {
    max-width: 800px;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    color: var(--sketch-black);
    margin-bottom: 1rem;
}

.hero-content h1 span {
    color: var(--sky-blue);
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: var(--sketch-black);
}

.btn {
    padding: 0.8rem 2rem;
    background-color: var(--sky-blue);
    color: var(--white);
    border: none;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s;
    text-decoration: none;
}

.btn:hover {
    background-color: #3A80D2;
}

/* 产品介绍模块 */
.products {
    padding: 5rem 5%;
    background-color: var(--white);
}

.products h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--sketch-black);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.product-card {
    background-color: var(--light-gray);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

.product-card:hover {
    transform: translateY(-10px);
}

.product-card h3 {
    color: var(--sky-blue);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

/* 文章列表模块 */
.articles {
    padding: 5rem 5%;
    background: linear-gradient(45deg, #E8F1FF, var(--light-gray));
}

.articles h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--sketch-black);
}

.article-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2.5rem;
}

.article-card {
    background-color: var(--white);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    border-left: 5px solid var(--sky-blue);
}

.article-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: var(--sketch-black);
}

.article-card p {
    color: #555;
    margin-bottom: 1.5rem;
}

.article-card a {
    color: var(--sky-blue);
    text-decoration: none;
    font-weight: 600;
}

/* 下载页样式 */
.download-page {
    padding: 5rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.download-page h1 {
    font-size: 2.8rem;
    color: var(--sketch-black);
    margin-bottom: 3rem;
    text-align: center;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.download-card {
    background-color: var(--white);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    text-align: center;
}

.download-card h3 {
    color: var(--sky-blue);
    margin-bottom: 1rem;
}

/* 文章详情页 */
.article-detail {
    padding: 5rem 5%;
    max-width: 900px;
    margin: 0 auto;
    background-color: var(--white);
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.article-detail h1 {
    font-size: 2.5rem;
    color: var(--sketch-black);
    margin-bottom: 1.5rem;
    border-bottom: 2px solid var(--sky-blue);
    padding-bottom: 1rem;
}

.article-detail .meta {
    color: #777;
    margin-bottom: 2rem;
}

.article-detail p {
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

/* 404页面 */
.error-page {
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(90deg, var(--sky-blue), #6BA5F5);
    color: var(--white);
    text-align: center;
}

.error-page h1 {
    font-size: 8rem;
    margin-bottom: 1rem;
}

.error-page h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
}

.error-page a {
    color: var(--sketch-black);
    background-color: var(--white);
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: background-color 0.3s;
}

.error-page a:hover {
    background-color: var(--light-gray);
}

/* 页脚 */
.footer {
    padding: 2rem 5%;
    background-color: var(--sketch-black);
    color: var(--white);
    text-align: center;
}

/* 响应式适配 */
@media (max-width: 768px) {
    .floating-okx {
        width: 80px;
        right: 1rem;
    }
    .hero-content h1 {
        font-size: 2rem;
    }
    .products h2, .articles h2 {
        font-size: 2rem;
    }
}