/* 全局变量定义 - 轻松修改主题色 */
:root {
    --primary-color: #e07a5f;
    /* 温暖的赤陶色 */
    --secondary-color: #3d405b;
    /* 深邃的蓝灰色 */
    --accent-color: #f2cc8f;
    /* 柔和的沙黄色 */
    --text-color: #333333;
    --bg-color: #f4f1de;
    /* 米色背景，护眼且高级 */
    --white: #ffffff;
    --transition: all 0.3s ease;
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Open Sans', sans-serif;
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮样式 */
.btn-primary,
.btn-secondary {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 50px;
    font-weight: 600;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    border: 2px solid var(--primary-color);
}

.btn-primary:hover {
    background-color: transparent;
    color: var(--primary-color);
    transform: translateY(-3px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--white);
    border: 2px solid var(--white);
    margin-left: 15px;
}

.btn-secondary:hover {
    background-color: var(--white);
    color: var(--secondary-color);
    transform: translateY(-3px);
}

.btn-text {
    color: var(--primary-color);
    font-weight: 600;
    border-bottom: 2px solid transparent;
    transition: var(--transition);
}

.btn-text:hover {
    border-bottom-color: var(--primary-color);
}

/* 头部导航 */
.header {
    background-color: var(--white);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    height: 80px;
    display: flex;
    align-items: center;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 800;
    color: var(--secondary-color);
    letter-spacing: 1px;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: 30px;
}

.nav-list li a {
    font-weight: 500;
    color: var(--secondary-color);
    transition: var(--transition);
}

.nav-list li a:hover {
    color: var(--primary-color);
}

.nav-list .btn-primary {
    padding: 10px 25px;
    color: var(--white);
}

.nav-list .btn-primary:hover {
    color: var(--primary-color);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-btn span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--secondary-color);
    margin: 5px 0;
    transition: var(--transition);
}

/* Hero 区域 */
.hero {
    height: 100vh;
    background-image: url('https://via.placeholder.com/1920x1080/3d405b/ffffff?text=African+Community+Culture');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    color: var(--white);
    margin-top: 0;
    /* 覆盖默认 */
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    /* 黑色半透明遮罩 */
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    animation: fadeInUp 1s ease-out;
}

.hero h1 {
    font-family: var(--font-heading);
    font-size: 4rem;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 40px;
    opacity: 0.9;
}

/* 通用部分样式 */
.section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 15px;
}

.section-header p {
    color: #666;
    font-size: 1.1rem;
}

/* 网格布局 */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

/* 卡片样式 */
.card {
    background: var(--white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
    transition: var(--transition);
    text-align: center;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    display: inline-block;
}

.card h3 {
    margin-bottom: 15px;
    color: var(--secondary-color);
}

/* 视觉展示区 */
.vision-section {
    background-color: var(--white);
}

.vision-image img {
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.vision-text h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.feature-list {
    margin: 30px 0;
}

.feature-list li {
    margin-bottom: 15px;
    font-size: 1.1rem;
}

/* 底部 */
.footer {
    background-color: var(--secondary-color);
    color: var(--white);
    padding: 80px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 60px;
}

.footer-col h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--accent-color);
}

.footer-col h4 {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

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

.footer-col ul li a:hover {
    color: var(--accent-color);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    opacity: 0.7;
}

/* 移动端菜单样式 */
.mobile-nav {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    background-color: var(--white);
    padding: 20px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    transform: translateY(-150%);
    transition: var(--transition);
    z-index: 999;
}

.mobile-nav.active {
    transform: translateY(0);
}

.mobile-nav-list li {
    margin-bottom: 15px;
    text-align: center;
}

.mobile-nav-list li a {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--secondary-color);
}

/* 动画定义 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式适配 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }

    .nav {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }

    .grid-2 {
        grid-template-columns: 1fr;
    }

    .vision-image {
        order: -1;
        /* 图片在上方 */
    }

    .btn-secondary {
        margin-left: 0;
        margin-top: 15px;
        display: block;
        width: fit-content;
        margin: 15px auto 0;
    }
}