/* 全局重置 + 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft YaHei", sans-serif;
}

:root {
    --tg-blue: #0088cc;
    --tg-dark: #333;
    --tg-light: #f5f5f5;
    --white: #fff;
}

body {
    color: var(--tg-dark);
    line-height: 1.6;
    padding-top: 70px; /* 适配固定导航栏 */
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 0;
}

/* 长款固定导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 999;
    height: 70px;
    display: flex;
    align-items: center;
}

.nav-container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--tg-blue);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--tg-dark);
    font-size: 1rem;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--tg-blue);
}

.download-btn {
    background: var(--tg-blue);
    color: var(--white) !important;
    padding: 0.5rem 1rem;
    border-radius: 4px;
}

.download-btn:hover {
    background: #0077b3;
}

/* 主页区块样式 */
.hero-section {
    background: linear-gradient(135deg, #0088cc, #00aaff);
    color: var(--white);
    text-align: center;
    padding: 6rem 0;
}

.hero-section h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-section p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.primary-btn {
    display: inline-block;
    background: var(--white);
    color: var(--tg-blue);
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    transition: transform 0.3s;
}

.primary-btn:hover {
    transform: scale(1.05);
}

/* 功能/教程/FAQ 通用样式 */
section {
    padding: 4rem 0;
    scroll-margin-top: 80px; /* 锚点跳转适配导航栏 */
}

section h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--tg-blue);
}

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

.feature-item {
    padding: 2rem;
    background: var(--tg-light);
    border-radius: 10px;
}

/* 下载页样式 */
.download-section {
    text-align: center;
    padding: 4rem 0;
}

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

.download-item {
    background: var(--tg-light);
    padding: 2rem;
    border-radius: 10px;
    text-decoration: none;
    color: var(--tg-dark);
    transition: 0.3s;
}

.download-item:hover {
    background: var(--tg-blue);
    color: var(--white);
}

/* 中文说明页 */
.cn-section {
    max-width: 800px;
    margin: 0 auto;
    line-height: 2;
}

.cn-section h2 {
    margin-top: 2rem;
    text-align: left;
}

/* 页脚 */
footer {
    background: var(--tg-dark);
    color: var(--white);
    text-align: center;
    padding: 1.5rem 0;
    margin-top: 2rem;
}

/* 响应式适配 */
@media (max-width: 768px) {
    .nav-menu {
        gap: 1rem;
    }
    .hero-section h1 {
        font-size: 2rem;
    }
}