/* styles.css */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #333;
    background: linear-gradient(to bottom, #3dbeba, #003366); /* 从顶部的#3dbeba渐变到底部的深蓝色 */
}

.container {
    background: linear-gradient(to bottom, #3dbeba, white);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background-color: transparent; /* 移除背景色 */
    max-width: 1200px; /* 设置最大宽度 */
    margin: 0 auto; /* 使导航栏居中 */
}

.logo {
    color: #3dbeba;
    font-size: 1.5rem;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1rem;
}

.nav-links a {
    color: #fff;
    text-decoration: none;
    transition: background-color 0.3s;
    display: flex;
    align-items: center;
    padding: 0.5rem 1rem;
    border-radius: 5px;
}

.nav-links a:hover {
    background-color: rgba(255, 255, 255, 0.1); /* 添加背景颜色，文字颜色不变 */
}
.btn {
    padding: 1rem 2rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.register {
    background-color: #3dbeba;
    color: #fff;
}

.register:hover {
    background-color: #2a9e87;
}

.free-register {
    background-color: #fff;
    color: #3dbeba;
    border: 2px solid #3dbeba; /* 添加边框 */
}

.free-register:hover {
    background-color: #f2f2f2;
    color: #3dbeba;
    border-color: #3dbeba; /* 保持边框颜色一致 */
}
.icon {
    width: 1.5rem;
    margin-right: 0.5rem;
    color: #fff; /* 图标颜色 */
}

.hero {
    color: #fff;
    text-align: center;
    padding: 5rem 2rem;
    background-color: transparent; /* 移除背景色 */
}

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

.hero p {
    font-size: 1.5rem;
    margin-bottom: 2rem;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.btn {
    padding: 1rem 2rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.register {
    background-color: #3dbeba;
    color: #fff;
}

.register:hover {
    background-color: #2a9e87;
}

.test {
    background-color: #fff;
    color: #3dbeba;
}

.test:hover {
    background-color: #f2f2f2;
}

.features {
    display: flex;
    flex-direction: row; /* 横向排列 */
    justify-content: center;
    gap: 2rem;
    padding: 2rem;
    background-color: #c8e6c9; /* 草绿色背景 */
    flex-wrap: wrap; /* 允许换行 */
}

.section-title {
    font-size: 2rem;
    margin-bottom: 2rem;
    text-align: center; /* 确保标题居中对齐 */
}

.feature-item {
    background-color: #fff;
    border-radius: 10px; /* 圆角 */
    padding: 2rem;
    text-align: center;
    width: 300px; /* 固定宽度 */
    height: 200px; /* 固定高度 */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1); /* 添加阴影 */
}

.feature-item .icon {
    font-size: 60px;
    width: 60px; /* 增加图标宽度 */
    height: 60px; /* 增加图标高度 */
    color: #3dbeba; /* 图标颜色 */
    margin-bottom: 1rem;
}

.feature-item h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.feature-item p {
    font-size: 1rem;
}

footer {
    background-color: #3dbeba;
    color: #fff;
    text-align: center;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    bottom: 0;
}

@media (max-width: 768px) {
    .features {
        flex-direction: column; /* 在小屏幕上改为纵向排列 */
        align-items: center;
    }

    .feature-item {
        width: 100%; /* 占据整个宽度 */
        max-width: 300px; /* 最大宽度 */
        margin-bottom: 1rem; /* 添加底部间距 */
    }
}